TY - JOUR A1 - Fa, X. A1 - Lin, Sh. A1 - Yang, J. A1 - Shen, Ch. A1 - Liu, Y. A1 - Gong, Y. A1 - Qin, A. A1 - Ou, Jun A1 - Resch-Genger, Ute T1 - −808 nm-activated Ca2+ doped up-conversion nanoparticles that release no inducing liver cancer cell (HepG2) apoptosis N2 - Anear-infrared (NIR) light-triggered release method for nitric oxide (NO) was developed utilizing core/shell NaYF4: Tm/Yb/Ca@NaGdF4:Nd/Yb up-conversion nanoparticles (UCNPs) bearing a mesoporous silica (mSiO2) shell loaded with theNOdonor S-nitroso-N-acetyl-DL-penicillamine (SNAP). To avoid overheating in biological samples, Nd3+ was chosen as a sensitizer, Yb3+ ions as the bridging sensitizer, andTm3+ ions as UV-emissive activator while co-doping with Ca2+ was done to enhance the luminescence of the activatorTm3+.NOrelease from SNAP was triggered by an NIR-UV up-conversion process, initiated by 808nmlight absorbed by the Nd3+ ions.NOrelease was confirmed by the Griess method. Under 808nmirradiation, the viability of the liver cancer cell line HepG2 significantly decreased with increasing UCNPs@mSiO2-SNAP concentration. For a UCNPs@mSiO2-SNAP concentration of 200 μgml−1, the cell survival probability was 47%. These results demonstrate that UCNPs@mSiO2-SNAP can induce the release of apoptosis-inducingNOby NIR irradiation. KW - Nano KW - Nanomaterial KW - Upconversion nanoparticle KW - Lanthanide KW - Photoluminescence KW - Quantum yield KW - Photophysics KW - Lifetime KW - Sensor KW - Excitation power density KW - Brightness KW - NIR KW - Mechanism KW - Triggered KW - Release KW - Cell KW - PDT KW - Dye KW - Therapy KW - Surface KW - Coating PY - 2022 DO - https://doi.org/10.1088/2050-6120/ac5524 VL - 10 IS - 2 SP - 1 EP - 9 PB - IOP Publishing AN - OPUS4-54842 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Balderas-Xicohtencatl, R. A1 - Villajos Collado, José Antonio A1 - Casabán, J. A1 - Wong, D. A1 - Maiwald, Michael A1 - Hirscher, M. T1 - ZIF‑8 Pellets as a Robust Material for Hydrogen Cryo-Adsorption Tanks N2 - Cryoadsorption on the inner surface of porous materials is a promising solution for safe, fast, and reversible hydrogen storage. Within the class of highly porous metal−organic frameworks, zeolitic imidazolate frameworks (ZIFs) show high thermal, chemical, and mechanical stability. In this study, we selected ZIF-8 synthesized mechanochemically by twin-screw extrusion as powder and pellets. The hydrogen storage capacity at 77 K and up to 100 bar has been analyzed in two laboratories applying three different measurement setups showing a high reproducibility. Pelletizing ZIF-8 increases the packing density close to the corresponding value for a single crystal without loss of porosity, resulting in an improved volumetric hydrogen storage capacity close to the upper limit for a single crystal. The high volumetric uptake combined with a low and constant heat of adsorption provides ca. 31 g of usable hydrogen per liter of pellet assuming a temperature−pressure swing adsorption process between 77 K − 100 bar and 117 K − 5 bar. Cycling experiments do not indicate any degradation in storage capacity. The excellent stability during preparation, handling, and operation of ZIF-8 pellets demonstrates its potential as a robust adsorbent material for technical application in pilot- and full-scale adsorption vessel prototypes. KW - Hydrogen adsorption storage KW - Metal−organic frameworks KW - ZIF-8 KW - Cryoadsorption KW - Hydrogen Storage KW - MefHySto PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569473 DO - https://doi.org/10.1021/acsaem.2c03719 SN - 2574-0962 SP - 1 EP - 8 PB - ACS Publications CY - Washington DC AN - OPUS4-56947 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rühle, Bastian A1 - Krumrey, Julian Frederic A1 - Hodoroaba, Vasile-Dan T1 - Workflow towards automated segmentation of agglomerated, non‑spherical particles from electron microscopy images using artificial neural networks N2 - We present a workflow for obtaining fully trained artificial neural networks that can perform automatic particle segmentations of agglomerated, non-spherical nanoparticles from scanning electron microscopy images “from scratch”, without the need for large training data sets of manually annotated images. The whole process only requires about 15 minutes of hands-on time by a user and can typically be finished within less than 12 hours when training on a single graphics card (GPU). After training, SEM image analysis can be carried out by the artificial neural network within seconds. This is achieved by using unsupervised learning for most of the training dataset generation, making heavy use of generative adversarial networks and especially unpaired image-to-image translation via cycle-consistent adversarial networks. We compare the segmentation masks obtained with our suggested workflow qualitatively and quantitatively to state-of-the-art methods using various metrics. Finally, we used the segmentation masks for automatically extracting particle size distributions from the SEM images of TiO2 particles, which were in excellent agreement with particle size distributions obtained manually but could be obtained in a fraction of the time. KW - Electron microscopy KW - Neural networks KW - Artificial intelligence KW - Image segmentation KW - Automated image analysis PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522454 DO - https://doi.org/10.1038/s41598-021-84287-6 VL - 11 IS - 1 SP - 4942 PB - Springer Nature AN - OPUS4-52245 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Winckelmann, Alexander T1 - Why do I have to charge my phone twice a day? N2 - Aging Mechanisms of Lithium Batteries: How can we make batteries more durable and more sustainable in the future? Lithium batteries are particularly susceptible to ageing processes. During each charging and discharging process in an electric battery, lithium ions are deposited in the electrodes of the cell like in the pores of a sponge. Over time, however, fractures and cracks occur in the filigree structures. The result: more and more lithium ions no longer fit into the hollow spaces of the „sponge“, instead they accumulate in heaps around the electrodes and hinder the movement of other ions. The performance of the battery decreases. We present our new project, in which we are developing a fast and cost-effective method with which companies that produce lithium batteries can already assess the ageing behaviour of their batteries in the laboratory. T2 - Berlin Science Week 2022 CY - Online meeting DA - 10.11.2022 KW - Lithium Ion Batteries KW - Aging Mechanisms PY - 2022 UR - https://berlinscienceweek.com/de/event/why-do-i-have-to-charge-my-phone-twice-a-day/ UR - https://www.youtube.com/watch?v=bF7bQTY49rQ AN - OPUS4-56245 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tavernaro, Isabella T1 - Where Do We Stand – Quantifying Amino Groups on Silica (Nano)Particles N2 - Industry and regulators are increasingly requesting validated and standardized measurement protocols to support the manufacturing, quality control, and safe use of engineered nanomaterials. Addressing a remaining gap in method development and standardization for nanomaterial characterization, we investigated in a bilateral comparison various methods commonly used for surface functional group quantification, like quantitative nuclear magnetic resonance (qNMR) spectroscopy, x-ray photoelectron spectroscopy (XPS), and optical assays. These results demonstrate not only an influence of the size and synthesis methods on the number of surface functional groups for differently sized commercial and in-house synthesized silica nanoparticles but also on their functionality. T2 - Kickoff-Meeting SMURFnano CY - Berlin, Germany DA - 09.07.2024 KW - Nano KW - Particles KW - Silica KW - Synthesis KW - Quantification KW - Functional groups KW - Quality assurance KW - Reference material KW - Interlaboratory comparison KW - Method KW - Uncertainty KW - Sensor KW - Surface analysis PY - 2024 AN - OPUS4-62164 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lisec, Jan T1 - When drowning in data - start swimming N2 - A presentation on the subject of Automatic Data Processing Skills in Chemistry to Enhance Scientific Research. T2 - 7th PhD Seminar of the German Working Group for Analytical Spectroscopy (DAAS) in the GDCh Division of Analytical Chemistry CY - Berlin, Germany DA - 15.11.2023 KW - Data KW - Automation KW - Programming PY - 2023 AN - OPUS4-58902 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique T1 - What does GD-OES reveal about the aging and manufacturing processes of lithium-ion batteries? N2 - Glow-Discharge Optical Emission Spectroscopy (GD-OES), a powerful analytical technique, sheds light on the two critical aspects of lithium-ion batteries (LIBs): manufacturing and aging 1, 2. We optimized cell production in manufacturing by adjusting parameters, including cathode doping, electrolyte concentration, and pressing force. GD-OES provided in-depth elemental composition and homogeneity analysis, which is crucial for identifying optimal manufacturing conditions. These findings were validated by electrochemical impedance spectroscopy, confirming the quality of the manufactured batteries. Shifting the focus to aging, we use GD-OES for fluorine depth profiling, a key element in understanding polymer and electrolyte degradation. However, fluorine presents analytical challenges. We addressed this by substituting argon with a neon:argon mixture, which significantly enhanced fluorine detection sensitivity. This advancement not only improves accuracy but also holds the potential to guide sustainable and cost-efficient manufacturing strategies. Through its versatility, GD-OES has proven to be a powerful tool for not only optimizing LIB manufacturing processes but also gaining deeper insights into their aging mechanisms. This research extends beyond academic interest, offering tangible benefits for the industry by translating into improved battery quality, extended lifespan, and overall performance. T2 - The 6th International Glow Discharge Spectroscopy Symposium CY - Liverpool, United Kingdom DA - 21.04.2024 KW - GD-OES KW - Depth profiles KW - Lithium KW - Battery KW - Fluorine KW - Aging KW - Manufacturing KW - Glow-discharge PY - 2024 AN - OPUS4-59945 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meermann, Björn T1 - Von Elementspezies, Isotope und Zellen oder: wie kommt man eigentlich von Westfalen nach Berlin N2 - Im Rahmen des Vortrages werden die Möglichkeiten der Elementanalytik an Applikationsbeispielen aus Umwelt und life-sciences aufgezeigt. Hierbei kommen ICP-MS Kopplungstechniken, stabile Isotope und Einzellen- und Partikelanalytik (sc-/sp-ICP-ToF-MS) zum Einsatz. T2 - DAAS PhD Seminar CY - Online meeting DA - 20.09.2021 KW - Elementspezies & Isotope KW - ICP-MS & HR-CS-GFMAS KW - Kopplungstechniken PY - 2021 AN - OPUS4-53378 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Golusda, L. A1 - Kühl, A. A. A1 - Lehmann, M. A1 - Dahlke, K. A1 - Mueller, S. A1 - Boehm-Sturm, P. A1 - Saatz, Jessica A1 - Traub, Heike A1 - Schnorr, J. A1 - Freise, C. A1 - Taupitz, M. A1 - Biskup, K. A1 - Blanchard, V. A1 - Klein, O. A1 - Sack, I. A1 - Siegmund, B. A1 - Paclik, D. T1 - Visualization of inflammation in experimental colitis by magnetic resonance imaging using very small superparamagnetic iron oxide particles N2 - Inflammatory bowel diseases (IBD) comprise mainly ulcerative colitis (UC) and Crohn´s disease (CD). Both forms present with a chronic inflammation of the (gastro) intestinal tract, which induces excessive changes in the composition of the associated extracellular matrix (ECM). In UC, the inflammation is limited to the colon, whereas it can occur throughout the entire gastrointestinal tract in CD. Tools for early diagnosis of IBD are still very limited and highly invasive and measures for standardized evaluation of structural changes are scarce. To investigate an efficient non-invasive way of diagnosing intestinal inflammation and early changes of the ECM, very small superparamagnetic iron oxide nanoparticles (VSOPs) in magnetic resonance imaging (MRI) were applied in two mouse models of experimental colitis: the dextran sulfate sodium (DSS)-induced colitis and the transfer model of colitis. For further validation of ECM changes and inflammation, tissue sections were analyzed by immunohistochemistry. For in depth ex-vivo investigation of VSOPs localization within the tissue, Europium-doped VSOPs served to visualize the contrast agent by imaging mass cytometry (IMC). VSOPs accumulation in the inflamed colon wall of DSS-induced colitis mice was visualized in T2* weighted MRI scans. Components of the ECM, especially the hyaluronic acid content, were found to influence VSOPs binding. Using IMC, colocalization of VSOPs with macrophages and endothelial cells in colon tissue was shown. In contrast to the DSS model, colonic inflammation could not be visualized with VSOP-enhanced MRI in transfer colitis. VSOPs present a potential contrast agent for contrast-enhanced MRI to detect intestinal inflammation in mice at an early stage and in a less invasive manner depending on hyaluronic acid content. KW - Inflammation KW - Imaging KW - Immunohistochemistry KW - MRI KW - Nanoparticle KW - Extracellular matrix KW - Laser ablation KW - ICP-MS PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-555395 DO - https://doi.org/10.3389/fphys.2022.862212 SN - 1664-042X VL - 13 IS - July 2022 SP - 1 EP - 15 PB - Frontiers Research Foundation CY - Lausanne AN - OPUS4-55539 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kader, A. A1 - Brangsch, J. A1 - Reimann, C. A1 - Kaufmann, Jan Ole A1 - Mangarova, D. B. A1 - Moeckel, J. A1 - Adams, L. C. A1 - Zhao, J. A1 - Saatz, Jessica A1 - Traub, Heike A1 - Buchholz, R. A1 - Karst, U. A1 - Hamm, B. A1 - Makowski, M. R. T1 - Visualization and Quantification of the Extracellular Matrix in Prostate Cancer Using an Elastin Specific Molecular Probe N2 - One of the most commonly diagnosed cancers in men is prostate cancer (PCa). Understanding tumor progression can help diagnose and treat the disease at an early stage. Components of the extracellular matrix (ECM) play a key role in the development and progression of PCa. Elastin is an essential component of the ECM and constantly changes during tumor development. This article visualizes and quantifies elastin in magnetic resonance imaging (MRI) using a small molecule probe. Results were correlated with histological examinations. Using an elastin-specific molecular probe, we were able to make predictions about the cellular structure in relation to elastin and thus draw conclusions about the size of the tumor, with smaller tumors having a higher elastin content than larger tumors. Human prostate cancer (PCa) is a type of malignancy and one of the most frequently diagnosed cancers in men. Elastin is an important component of the extracellular matrix and is involved in the structure and organization of prostate tissue. The present study examined prostate cancer in a xenograft mouse model using an elastin-specific molecular probe for magnetic resonance molecular imaging. Two different tumor sizes (500 mm3 and 1000 mm3) were compared and analyzed by MRI in vivo and histologically and analytically ex vivo. The T1-weighted sequence was used in a clinical 3-T scanner to calculate the relative contrast enhancement before and after probe administration. Our results show that the use of an elastin-specific probe enables better discrimination between tumors and surrounding healthy tissue. Furthermore, specific binding of the probe to elastin fibers was confirmed by histological examination and laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS). Smaller tumors showed significantly higher signal intensity (p > 0.001), which correlates with the higher proportion of elastin fibers in the histological evaluation than in larger tumors. A strong correlation was seen between relative enhancement (RE) and Elastica–van Gieson staining (R2 = 0.88). RE was related to inductively coupled plasma–mass spectrometry data for Gd and showed a correlation (R2 = 0.78). Thus, molecular MRI could become a novel quantitative tool for the early evaluation and detection of PCa. KW - Magnetic resonance imaging KW - MRI KW - Molecular imaging KW - Cancer KW - LA-ICP-MS PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538410 DO - https://doi.org/10.3390/biology10111217 VL - 10 IS - 11 SP - 1 EP - 14 PB - MDPI CY - Basel AN - OPUS4-53841 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Adamus, A. A1 - Ali, I. A1 - Vasileiadis, V. A1 - Al-Hileh, L. A1 - Lisec, Jan A1 - Frank, M. A1 - Seitz, G. A1 - Engel, N. T1 - Vincetoxicum arnottianum modulates motility features and metastatic marker expression in pediatric rhabdomyosarcoma by stabilizing the actin cytoskeleton N2 - Background: Prevention of metastatic invasion is one of the main challenges in the treatment of alveolar rhabdomyosarcoma. Still the therapeutic options are limited. Therefore, an anti-tumor screening was initiated focusing on the anti-metastatic and anti-invasion properties of selected medicinal plant extracts and phytoestrogens, already known to be effective in the prevention and treatment of different cancer entities. Methods: Treatment effects were first evaluated by cell viability, migration, invasion, and colony forming assays on the alveolar rhabdomyosarcoma cell line RH-30 in comparison with healthy primary cells. Results: Initial anti-tumor screenings of all substances analyzed in this study, identified the plant extract of Vincetoxicum arnottianum (VSM) as the most promising candidate, harboring the highest anti-metastatic potential. Those significant anti-motility properties were proven by a reduced ability for migration (60%), invasion (99%) and colony formation (61%) under 48 h exposure to 25 μg/ml VSM. The restricted motility features were due to an induction of the stabilization of the cytoskeleton – actin fibers were 2.5-fold longer and were spanning the entire cell. Decreased proliferation (PCNA, AMT, GCSH) and altered metastasis (e. g. SGPL1, CXCR4, stathmin) marker expression on transcript and protein level confirmed the significant lowered tumorigenicity under VSM treatment. Finally, significant alterations in the cell metabolism were detected for 25 metabolites, with levels of uracil, N-acetyl serine and propanoyl phosphate harboring the greatest alterations. Compared to the conventional therapy with cisplatin, VSM treated cells demonstrated a similar metabolic shutdown of the primary cell metabolism. Primary control cells were not affected by the VSM treatment. Conclusions: This study revealed the VSM root extract as a potential, new migrastatic drug candidate for the putative treatment of pediatric alveolar rhabdomyosarcoma with actin filament stabilizing properties and accompanied by a marginal effect on the vitality of primary cells. KW - Mass Spectroscopy KW - Metabolomics KW - Cancer PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-533530 DO - https://doi.org/10.1186/s12906-021-03299-x VL - 21 IS - 1 PB - Springer Nature AN - OPUS4-53353 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique T1 - Versatility of nitrogen microwave-induced plasma mass spectrometry in elemental and isotopic analysis N2 - The introduction of Nitrogen-based Microwave Inductively Coupled Atmospheric-Pressure Plasma Mass Spectrometry (MICAP-MS) addresses the necessity for a plasma source that matches the capabilities of traditional argon-based Inductively Coupled Plasma Mass Spectrometry (ICP-MS) while exploiting the availability and cost-effectiveness of nitrogen gas. MICAP-MS uses nitrogen plasma, offering significant advantages such as reduced operational costs and eliminating specific isobaric interferences common in argon plasma systems [1]. This presentation explores the principles of MICAP-MS, highlighting its similarities to conventional ICP-MS in terms of analytical performance while emphasizing unique benefits like eliminating interferences from argon-based polyatomic species. MICAP-MS exhibits robust performance using nitrogen gas of varying purities—including ultra-high purity and industrial-grade nitrogen—without compromising analytical results [2]. We have applied MICAP-MS for multielement analysis in soil samples, serving as a proof of concept for environmental monitoring applications. The technique achieved figures of merit comparable to traditional ICP-MS, even when analyzing real-world samples with complex matrices [2]. MICAP-MS demonstrated high tolerance to high-concentration matrices, maintaining accuracy and precision without extensive sample preparation or matrix separation [3]. In clinical diagnostics, MICAP-MS was employed for the precise and traceable quantification of calcium, iron, and selenium in human serum using isotope dilution analysis [4]. These elements often face interferences in argon-based ICP-MS due to argon-associated isobaric interferences (40Ca+, 56Fe+, and 80Se+); however, MICAP-MS effectively overcomes these challenges, providing traceable and accurate determinations. The stability of the microwave plasma in MICAP-MS facilitates precise isotopic analysis. This capability investigated age-induced lithium isotope fractionation in lithium-ion batteries, offering critical insights into battery aging mechanisms and performance degradation [5]. MICAP-MS is a versatile analytical tool that combines the operational benefits of nitrogen plasma with the strengths of traditional ICP-MS. Its ability to handle complex matrices, reduce interferences, and perform precise elemental and isotopic analyses across various applications makes it a valuable instrument. T2 - European Winter Conference on Plasma Spectrochemistry CY - Berlin, Germany DA - 02.03.2025 KW - MICAP-MS KW - Nitrogen plasma KW - Isotope dilution analysis KW - Matrix tolerance KW - Argon interference elimination KW - Trace analysis PY - 2025 AN - OPUS4-63485 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rosenkranz, D. A1 - Kriegel, F. L. A1 - Mavrakis, E. A1 - Pergantis, S. A. A1 - Reichardt, P. A1 - Tentschert, J. A1 - Jakubowski, N. A1 - Laux, P. A1 - Panne, Ulrich A1 - Luch, A. T1 - Versatile dual-inlet sample introduction system for multi-mode single particle inductively coupled plasma mass spectrometry N2 - Metal-containing nanoparticles (NP) can be characterized with inductively coupled plasma mass spectrometers (ICP-MS) in terms of their size and number concentration by using the single-particle mode of the instrument (spICP-MS). The accuracy of measurement depends on the setup, operational conditions of the instrument and specific parameters that are set by the user. The transport efficiency of the ICP-MS is crucial for the quantification of the NP and usually requires a reference material with homogenous size distribution and a known particle number concentration. Currently, NP reference materials are available for only a few metals and in limited sizes. If particles are characterized without a reference standard, the results of both size and particle number may be biased. Therefore, a dual-inlet Setup for characterizing nanoparticles with spICP-MS was developed to overcome this problem. This setup is based on a conventional introduction system consisting of a pneumatic nebulizer (PN) for nanoparticle solutions and a microdroplet Generator (μDG) for ionic calibration solutions. A new and flexible interface was developed to facilitate the coupling of μDG, PN and the ICP-MS system. The interface consists of available laboratory components and allows for the calibration, nanoparticle (NP) characterization and cleaning of the arrangement, while the ICP-MS instrument is still running. Three independent analysis modes are available for determining particle size and number concentration. Each mode is based on a different calibration principle. While mode I (counting) and mode III (μDG) are known from the literature, mode II (sensitivity), is used to determine the transport efficiency by inorganic ionic Standard solutions only. It is independent of NP reference materials. The μDG based inlet system described here guarantees superior analyte sensitivities and, therefore, lower detection limits (LOD). The size dependent LODs achieved are less than 15 nm for all NP (Au, Ag, CeO2) investigated. KW - Spectrometer KW - Reference KW - Calibration PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-536121 DO - https://doi.org/10.3791/61653 SN - 1940-087X IS - 163 SP - 1 EP - 19 PB - MyJoVE Corporation CY - Cambridge, MA, USA AN - OPUS4-53612 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Tavernaro, Isabella A1 - Abram, Sarah-Luise A1 - Homann, Christian A1 - Scholtz, Lena A1 - Radnik, Jörg T1 - Validated and standardized measurements and quantification of surface functionalities on nanoparticles N2 - Engineered nanoparticles (NPs) with various chemical compositions and surface functionalities are routinely fabricated for industrial applications such as medical diagnostics, drug delivery, sensing, catalysis, energy conversion and storage, opto-electronics, and information storage which improve the quality of life and European prosperity. Nanoparticle function, interaction with biological species, and environmental fate are largely determined by surface functionalities. Reliable, reproducible, and standardized surface characterization methods are therefore vital for quality control of NPs, and mandatory to meet increasing concerns regarding their safety. Also, industry, regulatory agencies, and policymakers need validated traceable measurement methods and reference materials. Industry, e.g., must comply with various regulations, including the chemicals´ regulation REACH (2006/1907) and cosmetic products regulation (2009/1223), depending on the use. Therefore, standardization organizations such as the European Committee for Standardization (CEN), the International Organization for Standardization (ISO), and the International Electrotechnical Commission (IEC) as well as industrial stakeholders, European Medicine Agency (EMA), and the nanosafety community responsible for guidelines for nanomaterial (NM) regulation like the Organisation for Economic Co-operation and Development (OECD) have expressed needs for standardized methodologies to measure NP surface chemical properties. Despite these needs, methodologies for determining NP surface properties, including the amount, chemical composition, and homogeneity of surface functionalities and coatings are largely non-standardized. Specifically, validated quantitative procedures for the measurement of thickness and composition of nanoparticle coatings and other surface functionalities are needed. Suitable methods for determining surface functionalities on ligand-stabilized core and core/shell NPs include advanced techniques such as traceable quantitative nuclear magnetic resonance (qNMR) as well as X-ray electron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF-SIMS), and simpler optical and electrochemical methods. The latter less costly methods are often used by SMEs, e.g., for quality control. To validate methods, establish measurement uncertainties, test reference materials, and produce reference data, international interlaboratory comparisons (ILC) on NP surface functionalization measurements are required. These needs have been addressed by us in two interlaboratory comparisons, that will be presented. In addition, the European metrology project SMURFnano will be briefly presented involving 12 partners from different National Metrology Institutes, designated institutes, and research institutes, two university groups as well as one large company and one SME producing NPs. T2 - NanoCarbon Annual Conference 2025 CY - Würzburg, Germany DA - 18.03.2025 KW - Nano KW - Particle KW - Silica KW - Quality assurance KW - Reference material KW - Surface chemistry KW - Size KW - Shape KW - Particle number concentration KW - Method KW - Optical assay KW - QNMR KW - Validation KW - Potentiometry KW - XPS PY - 2025 AN - OPUS4-62790 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tavernaro, Isabella A1 - Abram, Sarah-Luise A1 - Homann, Christian A1 - Scholtz, Lena A1 - Radnik, Jörg A1 - Resch-Genger, Ute T1 - Validated and standardized measurements and quantification of surface functionalities on nanoparticles N2 - Surface-functionalized organic and inorganic engineered nanomaterials (NMs) are widely applied in the life and materials sciences. NM performance depends on key factors such as particle size and shape, crystal phase, morphology, chemical composition, and surface chemistry, i.e., surface coatings, functional groups (FGs), and ligands.1 The latter controls their processability and interaction with the environment and largely their possible toxicity. Thus, methods for FG quantification are important tools for quality control of NM production processes and can foster the sustainable development of functional and safe(r) NMs. This underlines the importance of validated and standardized analytical methods for surface analysis and reference materials.2 This encouraged us to explore simple and versatile tools for quantifying common bioanalytically relevant FGs such as optical assays, electrochemical titration methods, quantitative nuclear magnetic resonance spectroscopy (qNMR), and X-Ray photoelectron spectroscopy (XPS) and to perform a first interlaboratory comparison (ILC) on surface FG quantification.3,4 In a follow-up ILC, BAM and NRC explored qNMR sample preparation, measurement, and data evaluation protocols for commercial and custom-made aminated SiO2 NPs with sizes of 20-100 nm, different amounts of surface amino FGs, and different porosity.5,6 First, the number of amino FGs accessible for a dye reporter was determined with a cost-efficient, automated optical fluorescamine assay. Then, qNMR workflows and protocols were stepwise fine-tuned. The qNMR ILC was complemented by joint XPS measurements. BAM also examined the applicability of fast and automatable potentiometric titrations to screen the total amount of (de)protonable FGs on aminated SiO2 NPs. Our results underline the need to evaluate protocols for FG quantification in ILCs and the advantages of multi-method characterization strategies for efficient method cross validation. T2 - Surface and Micro/Nano Analysis Working Group CY - Paris, France DA - 08.04.2025 KW - Quality assurance KW - Reference material KW - Fluorescence KW - Nano KW - Particle KW - Surface analysis KW - XPS KW - Traceability KW - Metrology KW - Calibration KW - Reference data KW - Reference product KW - Digital certificate KW - QNMR KW - Potentiometry PY - 2025 AN - OPUS4-62969 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pauli, Jutta A1 - Ramírez, A. A1 - Crasselt, C. A1 - Schmidt, W. A1 - Resch-Genger, Ute T1 - Utilizing optical spectroscopy and 2',7'-difluorofluorescein to characterize the early stages of cement hydration N2 - The increasingly sophisticated nature of modern, more environmentally friendly cementitious binders requires a better understanding and control particularly of the complex, dynamic processes involved in the early phase of cement hydration. In-situ monitoring of properties of a constantly changing system over a defined period of time calls for simple, sensitive, fast, and preferably also non-invasive methods like optical spectroscopy KW - Flourescence KW - Optical probe KW - Sensor KW - Dye KW - Flourescin KW - Photophysics KW - PH KW - Quantum yield KW - Quality assurance KW - Mechanism KW - Cement KW - Concrete KW - Building material KW - Hydration KW - Process monitoring PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537176 DO - https://doi.org/10.1088/2050-6120/ac2da0 SN - 2050-6120 VL - 10 IS - 1 SP - 2 EP - 13 PB - IOP Science AN - OPUS4-53717 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Palásti, Dávid Jenö T1 - Utilizing modern fiber lasers for LIBS N2 - The development of laser sources plays a very important role in the quick advancements in the field of LIBS. However, the development of fiber lasers went mostly unnoticed by the wider LIBS community. These laser sources, traditionally used in industrial cutting and welding processes, despite their high-power output (hundreds of watts) and are very robust nature, were neglected, because they used to work only in continuous mode. Modern fiber lasers however, offer pulsed output with a couple of mJ-s pulse energy, which can be adequate for certain tasks [1,2]. Furthermore, the pulse duration and the pulse repetition rate can be varied in a reasonably wide range, while their price is a fraction of the ones traditionally used in research. In the recent years, our groups made experiences with modern fiber lasers to evaluate the feasibility of their usage in LIBS. The initial experiments proved that they are not just suitable for standard analytical tasks such as quantitative or qualitative analysis, but their unique set of features makes them capable for fundamental research, like no other laser sources currently on the market. The relatively low energy and elongated profile of the pulses are very efficient in ablation and in the generation of low temperature plasmas [3], which means the ionic lines are less numerous, while the emission is mostly free from the background emission typical for the early stages of the plasma lifetime. It can make spectrometer gating and signal integration much simpler and robust. A thorough set of investigations of single pulse, double pulse and even continuous irradiation experiments was performed. The effects of various parameters, such as energy, duration and shape of the pulse as well as inter pulse delay were investigated on the generated signal focusing mainly the signal intensity, the self-absorption and the width of the peaks as well as the plasma properties. T2 - EMSLIBS 2026 CY - Senlis, France DA - 26.01.2026 KW - LIBS KW - Fiber laser PY - 2026 AN - OPUS4-65561 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Konthur, Zoltán T1 - Utilizing Aspergillus niger Fumonisin Amine Oxidase for the Electrochemical Detection of Fumonisin N2 - Fumonisins are a class of toxic secondary metabolites produced by various Fusarium species. The two most important producers of fumonisins are F. verticillioides and F. proliferatum but also Aspergillus niger is known to produce fumonisins. Most frequently they occur on maize, but also other grains can be contaminated with this group of mycotoxins. Exposure to fumonisins by dietary intake can have serious health effects on farm animals and also within humans. Thus, the European Commission sets legal limits for fumonisins in feed and foodstuffs. The detection of fumonisins is frequently performed in laboratories by chromatographic methods, which are costly and require trained personnel. Simplifying the analysis is therefore a major goal using portable detection systems. Electrochemical enzymatic biosensors offer great promise to meet this demand. Here we report for the first time an enzymatic fumonisin sensing approach with amperometric detection. For this purpose, an Aspergillus niger fumonisin amine oxidase (AnFAO) catalyzing the oxidative deamination of fumonisins, producing hydrogen peroxide, was recombinantly produced in E. coli. It was found that the specific activity of AnFAO using 20 μM Fumonisin B1 as substrate is higher than for 20 μM Fumonisin B2 with 0.122 U mg-1 and 0.058 U mg-1, respectively. It was possible to show a dependence of enzyme activity with enzyme – and substrate-concentration. For fumonisin B1 detection, the enzyme was coupled covalently to magnetic particles and the enzymatically produced H2O2 was detected amperometrically in a flow injection system using Prussian blue carbon electrodes. The developed method allows to quantify fumonisin B1 concentrations down to 1.5 µM and demonstrates that the recombinantly produced AnFAO was able to deaminate different concentrations of fumonisin even in immobilized form. Thus, this enzyme is well suited to develop an enzyme based electrochemical biosensor for fumonisin contaminated food and feed. T2 - Affinity 2023 - the 25th meeting of the International Society for Molecular Recognition CY - Lisbon, Portugal DA - 05.06.2023 KW - Mycotoxin KW - Amperometry KW - Biosensor KW - Food analysis PY - 2023 N1 - Geburtsname von Riedel, Soraya: Höfs, S. - Birth name of Riedel, Soraya: Höfs, S. AN - OPUS4-57717 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gawlitza, Kornelia T1 - Using Dual Fluorescent Molecularly Imprinted Particles Coupled with a Miniaturized Opto-Microfluidic Platform for On-Site Detection of Perfluoroalkyl Carboxylic Acids N2 - Per- and polyfluoroalkyl substances (PFAS) are a group of synthetic organofluorine chemicals widely used in the production of various materials, including firefighting foams, adhesives, and coatings that resist stains and oil. In recent years, PFAS have gained attention as emerging environmental contaminants, with particular emphasis on perfluoroalkyl carboxylic acids (PFCAs), the most common type of PFAS. PFCAs are defined by a fully fluorinated carbon chain and a charged carboxylic acid group. They have been classified as Substances of Very High Concern and included in the REACH Candidate List due to their persistence, resistance to biodegradation, and toxicological impacts. Traditional methods for analyzing PFCAs, like GC-MS, HRMS, and HPLC-based techniques, are time-consuming, non-portable, expensive, and require specialized expertise. On the other hand, fluorescence assays offer a user-friendly, portable, and cost-effective alternative with high sensitivity and quick results, particularly when the binding of the analyte causes a specific increase in the probe’s fluorescence. Combining these probes with a carrier platform and a miniaturized optofluidic device presents a promising approach for PFCA monitoring. In this study, a new guanidine BODIPY fluorescent indicator monomer was synthesized, characterized, and incorporated into a molecularly imprinted polymer (MIP) designed for the specific detection of perfluorooctanoic acid (PFOA). The MIP layer was formed on silica core nanoparticles doped with tris(bipyridine)ruthenium(II) chloride, serving as an optical internal reference for calibration-free assays. In combination with an extraction step prior to sample analysis, this system enables selective and reliable detection of PFCAs in surface water samples, minimizing interference from competing substances, matrix effects, and other factors. When integrated into an opto-microfluidic setup, the assay provided a compact, user-friendly detection system capable of detecting micromolar levels of PFOA in under 15 minutes from surface water samples. T2 - ANAKON2025 CY - Leipzig, Germany DA - 10.03.2025 KW - Perfluorooctanoic Acid (PFOA) KW - On-site detection KW - Fluorescence KW - Microfluidics KW - Molecularly Imprinted Polymers PY - 2025 AN - OPUS4-62712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hufgard, Josefin T1 - Use Your Time (Domain) Wisely: Streamlined Analysis of Complex Mixtures with Pulsed-Laser Techniques N2 - This study aims to streamline complex mixture analysis through the parallel ionization of all analytes without extensive preprocessing. Here, pulsed laser ablation of single droplets is used with modified cross-correlation, a phase-sensitive algorithm. This combined method allows contactless chemical investigation with minimal sample pretreatment, as well as the separation of analytes in mixtures and reconstruction of analyte-specific mass spectra. T2 - SciX 2024 CY - Raleigh, NC, USA DA - 20.10.2024 KW - MS KW - Data analysis KW - Laser ablation PY - 2024 AN - OPUS4-62120 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hufgard, Josefin T1 - Use Your Time (Domain) Wisely: Streamlined Analysis of Complex Mixtures with Pulsed-Laser Techniques N2 - This study aims to streamline complex mixture analysis through the parallel ionization of all analytes without extensive preprocessing. Here, pulsed laser ablation of single droplets is used with modified cross-correlation, a phase-sensitive algorithm. This combined method allows contactless chemical investigation with minimal sample pretreatment, as well as the separation of analytes in mixtures and reconstruction of analyte-specific mass spectra. T2 - Future WINS: Corss-sections and interfaces in science, careers, and communication CY - Berlin, Germany DA - 21.11.2024 KW - MS KW - Data analysis KW - Laser ablation PY - 2024 AN - OPUS4-62124 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hufgard, Josefin T1 - Use Your Time (Domain) Wisely: Streamlined Analysis of Complex Mixtures with Pulsed-Laser Techniques N2 - Analyzing complex mixtures with mass spectrometry (MS) usually requires extensive sample preprocessing and separation techniques such as high-pressure iquid chromatography (HPLC). This approach allows for subsequent detection of one analyte at a time but at a cost of throughput. Recently, increasing attention has been put on thesimultaneous ionization of all analytes in complex mixtures without extensive preprocessing, aiming to streamline the analysis process while accepting a compromise in identification. Such methods are commonly referred to as direct mass-spectrometric analysis. Among those, pulsed laser-based ablation, allows for contactless chemical investigation and reaction monitoring in situ, with minimal sample pretreatments. Specifically, the mid-infrared lasers encompass the fundamental vibrational resonances of typical biological matrices and solvents; their use results in efficient material removal from the bulk phase. Interestingly, the resulting analyte chronograms during the ablation process showed that the analytes were not detected concomitantly. Instead, chronograms offered time-domain information by being detected at different timestamps. It is certain that chemical information is encoded in the time domain. However, the analyte-specific chronograms could be difficult to interpret with conventional workflows as they mostly overlap. In this study, we aim exploiting the commonly discarded information in the time domain as an orthogonal dimension to the m/z domain, achieving ategorization and grouping mass-spectral peaks according to their chemical origins. Here, we applied a pulsed diode-pumped solid-state (DPSS) laser at 3-μm wavelength to 10 μL hanging droplets of analyte. A secondary electrospray ionization (SESI) source was built in-house to ionize ablated analytes. With a model sample, i.e. a mixture of two antibiotics, remarkable differences in their chronograms were observed. In fact, the time-domain information reflects the chemical signature of the analytes and can provide an additional data dimension for accurate interpretation. With a phase-sensitive algorithm, the modified cross-correlation (mXcorr), the similarity between chronograms can be gauged. Consequently, mass-spectral peaks that shared the same chronogram features were grouped together, yielding analyte-specific mass spectra that can aid analyte identification. Lastly, the applicability for biological samples, such as peptides, will be discussed. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - Mass specrometry KW - Laser Ablation KW - secondary ionization PY - 2024 AN - OPUS4-62733 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Danischewski, Julia L. A1 - You, Yi A1 - Bauer, Lauren A1 - Riedel, Jens A1 - Shelley, Jacob T. T1 - Use of Resonant Acoustic Fields as Atmospheric-Pressure Ion Gates N2 - Ion optics are crucial for spectrometric methods such as mass spectrometry (MS) and ion mobility spectrometry (IMS). Among the wide selection of ion optics, temporal ion gates are of particular importance for time-of-flight MS (TOF-MS) and drift-tube IMS. Commonly implemented as electrostatic ion gates, these optics offer a rapid, efficient means to block ion beams and form discrete ion packets for subsequent analysis. Unfortunately, these devices rely on pulsed high voltage sources and are not fully transparent, even in their open state, which can lead to ion losses and contamination. Here, a novel atmospheric-pressure ion gate based on a resonant acoustic field structure is described. This effect was accomplished through the formation of a resonant, standing acoustic wave of alternating nodes and antinodes. Alignment of an atmospheric-pressure gaseous ion beam with an antinode, i.e. a region of transient pressure, of the acoustic structure acted as a gate and blocked ions from impinging on ion-selective detectors, such as a mass spectrometer and a Faraday plate. The velocity of the ion stream and acoustic power were found to be critical parameters for gating efficiency. In the presence of an acoustic field (i.e., a closed gate), ion signals decreased by as much as 99.8% with a response time faster than the readout of the ion-measurement devices used here (ca. 75 ms). This work demonstrates the basis for a low-cost, acoustic ion gate, which is optically transparent and easily constructed with low-power, off-the-shelf components, that could potentially be used with MS and IMS instrumentation. KW - Acoustic Ion Manipulation PY - 2025 DO - https://doi.org/10.1021/acs.analchem.4c05493 SN - 1520-6882 VL - 97 IS - 5 SP - 2890 EP - 2898 PB - American Chemical Society AN - OPUS4-62648 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Russo, Francesco Friedrich T1 - Upscaling of spectral libraries for HREI- MS based non target analytics N2 - Gas Chromatography coupled with Electron Ionisation Mass Spectrometry (GC-EI-MS) is a well-established technique which, in combination with spectral libraries, has the potential to identify compounds in a sample. Nevertheless, most libraries are dominated by spectra with nominal mass resolution which does not allow to make full use of the data generated by modern high-resolution instruments. The production of high-resolution spectral library is time consuming and expensive, while in silico fragmentation tools that are capable of generating HR mass spectra are still too computationally intensive. We explored the alternative of using ML models to upscale existing spectral libraries. The models were trained with spectra from the RECETOX metabolome (DOI: 10.5281/zenodo.5483564), RECETOX Exposome (DOI: 10.5281/zenodo.4471216), and MassBank (10.5281/zenodo.7436394) HR-GC-MS libraries. The model was used to generate a synthetic library which was compared with a synthetic library simulated with CFM-ID (DOI: 10.1021/acs.analchem.6b01622). T2 - ANAKON 2023 CY - Vienna, Austria DA - 11.04.2023 KW - ML KW - GC-MS KW - EI-MS PY - 2023 AN - OPUS4-57358 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Russo, Francesco Friedrich T1 - Upscaling of spectral libraries for HR- EI-MS based non target analytics N2 - Non-target (NT) mass spectrometry techniques play a crucial role in metabolomics applications, particularly in areas such as environmental safety. Soft ionization methods, such as electrospray ionization (ESI), are commonly employed due to their ability to generate spectra containing molecular ions, aiding in the identification of unknown peaks. However, ESI may fail to ionize certain compounds effectively, resulting in their absence in NT approaches. In contrast, hard ionization methods like electron impact (EI) can ionize a wide range of compounds but often lack information about the molecular ion. Although extensive databases of EI spectra exist, their nominal mass resolution (NR) limits their utility for modern high-resolution (HR) EI mass spectrometers. Here, the often-applied conversion of HR spectra to nominal mass leads to the loss of unique characteristics, i.e. by grouping distinct masses into more ambiguous nominal masses. Our study aims to (i) quantify the negative impact of such a binning approach and (ii) develop a machine learning (ML) tool capable of enhancing existing nominal mass spectral libraries. In the initial phase, we employed the RECETOX Exposome HR-[EI+]-MS library to assess the influence of HR spectra on identification. We compared the dot product of each spectrum against all others, utilizing bin sizes of 0.001 and 1 Da. The difference in dot product between the second-best candidate and the query spectrum (the best candidate, with a score of 1) was calculated for both HR and nominal mass spectra. Subsequently, we explored the application of ML techniques to predict HR spectra from nominal mass spectra using the before mentioned dataset. Preliminary findings demonstrate the potential of high-resolution spectral libraries. As anticipated, HR spectra consistently exhibited lower similarity scores for the second candidate. This observation likely stems from the high redundancy and resulting ambiguity associated with nominal masses. Even after eliminating spectra containing multiple HR masses mapped to the same nominal mass, the aforementioned trend persisted. Furthermore, initial investigations into ML have revealed its ability to predict up to 40% of HR masses within a 10 mDa precision window. T2 - Tag der Chemie 2023 CY - Berlin, Deutschland DA - 05.07.2023 KW - HR-EI-MS KW - ML PY - 2023 AN - OPUS4-58172 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Oskoei, Párástu A1 - Afonso, Rúben A1 - Bastos, Verónica A1 - Nogueira, João A1 - Keller, Lisa-Marie A1 - Andresen, Elina A1 - Saleh, Maysoon I. A1 - Rühle, Bastian A1 - Resch-Genger, Ute A1 - Daniel-da-Silva, Ana L. A1 - Oliveira, Helena T1 - Upconversion Nanoparticles with Mesoporous Silica Coatings for Doxorubicin Targeted Delivery to Melanoma Cells N2 - Melanoma is one of the most aggressive skin cancers and requires innovative therapeutic strategies to overcome the limitations of conventional therapies. In this work, upconversion nanoparticles coated with mesoporous silica and functionalized with folic acid (UCNP@mSiO2-FA) were developed as a targeted nanocarrier system for the delivery of doxorubicin (DOX). The UCNPs were synthesized via thermal decomposition, coated with mesoporous silica shells, and functionalized with folic acid (FA) to enable receptor-mediated targeting. DOX was then loaded into the mesoporous silica coating by adsorption, yielding UCNP@mSiO2-FA-DOX. The different UCNPs were characterized for size, composition, colloidal stability, and loading and release of DOX. This comprehensive physicochemical characterization confirmed a high DOX loading efficiency and a slightly increased drug release under acidic conditions, mimicking the tumour microenvironment. In vitro assays using four melanoma cell lines (A375, B16-F10, MNT-1, and SK-MEL-28) revealed an excellent biocompatibility of UCNP@mSiO2-FA and a significantly higher cytotoxicity of UCNP@mSiO2-FA-DOX compared to unloaded UCNPs, in a dose-dependent manner. Cell cycle analysis demonstrated G2/M phase arrest after treatment with UCNP@mSiO2-FA-DOX, confirming its antiproliferative effect. Overall, UCNP@mSiO2-FA-DOX represents a promising nanoplatform for targeted melanoma therapy, combining active tumour targeting and enhanced anticancer efficacy. KW - Fluorescence KW - Synthesis KW - Nano KW - Particle KW - Silica KW - Cell KW - Uptake KW - Drug KW - Characterization KW - DOX KW - Imaging KW - Toxicity KW - Release KW - pH PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653596 DO - https://doi.org/10.3390/molecules31010074 SN - 1420-3049 VL - 31 IS - 1 SP - 1 EP - 18 PB - MDPI AG AN - OPUS4-65359 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kossatz, Philipp T1 - Upconversion Nanoparticles for Luminescent Barcodes and as Reporters for Optical Sensors N2 - Counterfeiting of goods has serious economic implications worldwide and can be a threat to human health and safety. Upconversion nanoparticles (UCNPs)are ideal candidates for optical encoding of various materials. Particles with tailor-made emission patterns can be used as anti-counterfeiting markers and luminophores in security inks and to track material flows. Microenvironment-specific changes in the emission properties of the UCNP tags can be used to study, signal, and sense changes of physico-chemical parameters in different environments, e.g., building materials. T2 - ANAKON 2023 CY - Vienna, Austria DA - 11.04.2023 KW - Nanomaterials KW - Anti-Counterfeiting KW - Fluorescence Spectroscopy PY - 2023 AN - OPUS4-59035 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kossatz, Philipp T1 - Upconversion Nanoparticles as Luminescent Probes for Cement N2 - Safety is a key parameter for the design and construction of buildings. The most widely used construction material to date is concrete that consists of about 15-20 wt.-% cement, which is responsible for the main concrete properties, i.e., strength and durability. Despite many standards regulating the quality of cement, at present, there exists no viable method to track the cement life cycle “from cradle to grave”. This led to an increasing interest in simple and robust methods for studying the processes and changes occurring during the life cycle of cement. In this context, we explored the applicability of fluorescence measurements which can be performed with relatively inexpensive and miniaturized instrumentation yet require robust optical probes which survive the harsh cement environment. Therefore, we developed a platform of lanthanide-based upconversion nanoparticles (UCNPs), consisting of a NaYF4 matrix doped with Yb3+ and Er3+ with sizes between 20 nm and 55 nm, which show characteristic multi-color emission patterns, composed of narrow bands of varying intensity in the ultraviolet, visible, near-infrared, and short-wave spectral region and examined their potential for cement probing and the non-invasive monitoring of the hydration processes occurring during cement formation. UCNPs of different size and chemical composition were synthesized via a thermal decomposition approach under inert conditions. The tailor-made design of different emission patterns was achieved by tuning particle size and morphology, material composition, and particle surface chemistry in upscaleable syntheses. For cement probing, different types of UCNPs were added to cement and the evolution of the UCNP emission pattern was used to probe in-situ changes of physico-chemical parameters in the cementitious environment during hydration, utilizing a simple and portable custom-designed optical setup. The observed changes in the UCNP emission patterns are characteristic for a given particle size, surface chemistry, and cement composition. In addition to fluorescence measurements, conventional isothermal heat flow calorimetry was used to study the influence of UCNP addition on cement hydration kinetics. Subsequently, both sets of measurements were correlated. Our results underline the potential of our optical approach ad UCNPs for the non-invasive probing of cementitious systems and cement hydration. This can be also exploited for cutting-edge applications of construction materials such as 3D concrete printing. T2 - Summer School Exciting Nanostructures CY - Bad Honnef, Germany DA - 31.07.2023 KW - Cement Hydration KW - Upconversion KW - Fluorescence Spectroscopy PY - 2023 AN - OPUS4-58203 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Scholl, Juliane A1 - Bagheri, Abbas A1 - Meiers, Emelie A1 - Lisec, Jan A1 - Russo, Francesco A1 - Haase, Hajo A1 - Koch, Matthias T1 - Unveiling Aging Mechanisms of Electrolytes in Commercial End-of-Life Lithium-Ion Batteries N2 - In this study, 77 end-of-life (EOL) commercial lithium-ion batteries (LIBs) of different formats were systematically analyzed to investigate electrolyte degradation mechanisms and the influence of pristine electrolyte composition on aging. Comprehensive chemical characterization employed targeted and non-targeted mass spectrometry (MS), combining liquid and gas chromatography (LC-MS/MS, GC-MS) with high-resolution MS (HRMS). This approach identified confirmed pristine components and complex degradation products. Commercial rechargeable pouch and cylindrical cells often deviated from conventional research model systems, using mixed lithium salt anions, ionic liquids (ILs), and high concentrations of triflates, triflimides, and bis(fluorosulfonyl)imide (FSI), functioning as solvents, salts, or additives. Specific IL degradation products and previously unreported pathways were proposed. A novel series of oligomerization products from propylene carbonate (PC) was also identified. In contrast, non-rechargeable coin cells showed prevalent use of per- and polyfluoroalkyl substances (PFAS) in their original electrolytes. Distinct PFAS degradation mechanisms were proposed for the first time. The absence of carbonate oligomers and lithium salt-derived products in coin cells, alongside standard carbonates, suggests lithium counterion coordination critically influences Lewis acid-catalyzed degradation. These findings provide new insight into real-world LIB aging, highlighting differences between commercial devices and model systems. KW - Mass Spectrometry KW - PFAS KW - Electrolyte degradation KW - Transformation products KW - Battery aging PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641059 DO - https://doi.org/10.2139/ssrn.5395937 SP - 1 EP - 15 PB - Elsevier BV AN - OPUS4-64105 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scholl, Juliane A1 - Lisec, Jan A1 - Bagheri, Abbas A1 - Meiers, Emelie A1 - Russo, Francesco Friedrich A1 - Haase, Hajo A1 - Koch, Matthias T1 - Unveiling aging mechanisms of electrolytes in commercial end-of-life lithium-ion batteries N2 - In this study, 77 end-of-life (EOL) commercial lithium-ion batteries (LIBs) of various formats were systematically analyzed to investigate electrolyte degradation and the influence of pristine electrolyte compositions on aging behavior. Comprehensive chemical characterization was conducted using targeted and non-targeted mass spectrometry (MS), employing LC-MS/MS, GC-MS, and high-resolution MS (HRMS). This integrated approach enabled the identification of confirmed pristine components and complex degradation products. The results show that rechargeable pouch and cylindrical cells often deviate from conventional model systems, containing mixed lithium salt anions, ionic liquids (ILs), and high concentrations of triflates, triflimides, and bis(fluorosulfonyl)imide (FSI). These function as solvents, salts, or safety-enhancing additives. Specific IL degradation products were identified, and hypotheses formulated on previously unreported pathways. Furthermore, a novel series of oligomerization products of propylene carbonate (PC) was detected. In contrast, non-rechargeable coin cells revealed widespread use of per- and polyfluoroalkyl substances (PFAS) in their original electrolytes. Based on ex situ analyses, hypothetical PFAS degradation mechanisms are proposed here for the first time. The absence of carbonate oligomers and lithium salt-derived products, alongside the presence of standard carbonates, indicates lithium counterion coordination as a key factor in Lewis acid-catalyzed degradation. This study offers valuable insights into real-world battery aging. KW - Transformation products KW - Lithium-ion batteries KW - Fluorinated Compounds KW - Gas chromatography/ QTOF-MS KW - HILIC-LC-MS/MS KW - PFAS KW - Electrochemistry PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644991 DO - https://doi.org/10.1016/j.jpowsour.2025.238613 SN - 0378-7753 VL - 661 SP - 1 EP - 10 PB - Elsevier B.V. AN - OPUS4-64499 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Traub, Heike T1 - Unraveling the interaction of MRI contrast agents with tissue using LA ICP MS N2 - Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is increasingly used to study the distribution of metal-containing drugs, imaging probes and nanomaterials in connection with disease related changes and therapy progress. Additionally, biomolecules can be detected indirectly by using metal-tagged antibodies. The extracellular matrix (ECM) is, besides the cells, an important component of all body tissues. The macromolecular network of the ECM consists of structural proteins (e.g., collagen, elastin) and proteoglycans composed of highly negatively charged carbohydrates, the glycosaminoglycans (GAGs), which are covalently linked to a protein core. Many diseases, including inflammatory processes and tumors, are associated with characteristic ECM changes at an early stage. Recent studies have shown that contrast agents for magnetic resonance imaging (MRI), which are based on gadolinium containing chelate complexes or iron oxide nanoparticles, can bind themselves to ECM components. To elucidate the role of GAGs like keratan sulfate (KS) and its modification state in disease, highly specific tools are necessary. As a complement to conventional immunohistochemistry LA-ICP-MS was applied to investigate the distribution of KS in tissue thin sections using a well characterized anti-KS antibody labelled with metal ions. Furthermore, LA-ICP-MS was used for the detection of MRI contrast agents and the identification of their target cells and molecules in tissue samples from animal models, e.g. for cardiovascular diseases. The results show the possibilities of LA-ICP-MS for the elucidation of pathological tissue changes. T2 - European Workshop on Laser Ablation (EWLA 2022) CY - Berne, Switzerland DA - 12.07.2022 KW - Laser ablation KW - Imaging KW - ICP-MS KW - Antibody PY - 2022 AN - OPUS4-55315 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Temgoua, Ranil C. T. T1 - Understanding the behavior of phenylurazoletyrosine- click electrochemical reaction N2 - The electrochemical behavior of 4-phenylurazole (Ph-Ur) was studied and the latter was used as a molecular anchor for the electrochemical bioconjugation of tyrosine (Y). Cyclic voltammetry (CV) and controlled potential coulometry (CPC) allowed to generate in situ from phenylurazole the PTAD (4-phenyl-3H-1,2,4-triazole-3,5(4H)-dione) species on demand for tyrosine electrolabeling. To evaluate the performance of tyrosine electrolabeling, coulometric analyses at controlled potentials were performed on solutions of phenylurazole and the phenylurazole-tyrosine mixture in different proportions (2:1, 1:1, and 1:2). The electrolysis of the phenylurazole-tyrosine mixture in the ratio (1:2) produced a charge of 2.07 C, very close to the theoretical value (1.93 C) with high reaction kinetics, a result obtained here for the first time. The products obtained were identified and characterized by liquid chromatography coupled to high-resolution electrospray ionization mass spectrometry (LC-HRMS and LC-HRMMS). Two products were formed from the click reactions, one of which was the majority. Another part of this work was to study the electrochemical degradation of the molecular anchor 4-phenylazole (Ph-Ur). Four stable degradation products of phenylurazole were identified (C7H9N2O, C6H8N, C6H8NO, C14H13N4O2) based on chromatographic profiles and mass spectrometry results. The charge generated during the electrolysis of phenylurazole (two-electron process) (2.85 C) is inconsistent with the theoretical or calculated charge (1.93 C), indicating that secondary/parasitic reactions occurred during the electrolysis of the latter. In conclusion, the electrochemically promoted click phenylurazole-tyrosine reactions give rise to click products with high reaction kinetics and yields in the (1:2) phenylurazole-tyrosine ratios, and the presence of side reactions is likely to affect the yield of the click phenylurazole-tyrosine reaction. T2 - Les Journées d’Électrochimie 2024 CY - Saint-Malo, France DA - 01.07.2024 KW - Electrochemistry KW - Mass Spectrometry KW - Simulation PY - 2024 AN - OPUS4-61063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Temgoua, Ranil C.T. A1 - Dontsi, Fabiola T. A1 - Lebègue, Estelle A1 - Thobie-Gautier, Christine A1 - Tonlé, Ignas K. A1 - Boujtita, Mohammed T1 - Understanding the behavior of phenylurazole-tyrosine-click electrochemical reaction using hybrid electroanalytical techniques N2 - In this work, the electrochemical behavior of 4-phenylurazole (Ph-Ur) was studied and the latter was used as a molecular anchor for the electrochemical bioconjugation of tyrosine (Y). Cyclic voltammetry (CV) and controlled potential coulometry (CPC) allowed the in-situ generation of the PTAD (4-phenyl-3 H-1,2,4-triazole-3,5(4 H)-dione) species from phenylurazole on demand for tyrosine electrolabeling. The chemoselectivity of the reaction was studied with another amino acid (lysine, Lys) and no changes in Lys were observed. To evaluate the performance of tyrosine electrolabeling, coulometric analyses at controlled potentials were performed on solutions of phenylurazole and the phenylurazole-tyrosine mixture in different proportions (2:1, 1:1, and 1:2). The electrolysis of the phenylurazole-tyrosine mixture in the ratio (1:2) produced a charge of 2.07 C, very close to the theoretical value (1.93 C), with high reaction kinetics, a result obtained here for the first time. The products obtained were identified and characterized by liquid chromatography coupled to high-resolution electrospray ionization mass spectrometry (LC-HRMS and LC- HRMS2). Two products were formed from the click reactions, one of which was the majority. Another part of this work was to study the electrochemical degradation of the molecular anchor 4-phenylazole (Ph-Ur). Four stable degradation products of phenylurazole were identified (C7H9N2O, C6H8N, C6H8NO, C14H13N4O2) based on chromatographic profiles and mass spectrometry results. The charge generated during the electrolysis of phenylurazole (two-electron process) (2.85 C) is inconsistent with the theoretical or calculated charge (1.93 C), indicating that secondary/parasitic reactions occurred during the electrolysis of the latter. In conclusion, the electrochemically promoted click phenylurazole-tyrosine reactions give rise to click products with high reaction kinetics and yields in the (1:2) phenylurazole-tyrosine ratios, and the presence of side reactions is likely to affect the yield of the click phenylurazole-tyrosine reaction. KW - Clinical Biochemistry KW - Spectroscopy KW - Drug Discovery KW - Pharmaceutical Science KW - Analytical Chemistry PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599267 DO - https://doi.org/10.1016/j.jpba.2024.116147 VL - 245 SP - 1 EP - 8 PB - Elsevier BV AN - OPUS4-59926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mesquita Silva da Veiga, Marcia T1 - Ultrasonic-assisted leaching of Li and Co from black mass using deep eutectic solvent N2 - The recovery of critical metals from spent lithium-ion batteries is a key strategy for sustainable resource management and the circular economy. Conventional hydrometallurgical processes typically rely on strong mineral acids and elevated temperatures, which, although effective, generate hazardous waste and demand high energy inputs. As a greener alternative, deep eutectic solvents (DES) combine low toxicity, non-volatility, simple synthesis, and tunable physicochemical properties, making them promising media for selective metal recovery1-2. Here, we report for the first time the use of ultrasound (US) to assist the leaching of Li and Co from LiCoO₂ black mass employing a deep eutectic solvent based on choline chloride and formic acid (ChCl:HCOOH, 1:2 molar ratio). The DES was synthesized at 90 °C for 3 h under stirring (300 rpm) and was characterized in terms of its molecular structure and formation by 1H-NMR and FT-IR, as well as by its viscosity and density. For each experiment, ~0.100 g of LiCoO2 was treated with 5 g of DES-FA in an ultrasonic bath (35 kHz, 60 °C) for different irradiation times (30–120 min), followed by three sequential extractions. All measurements were performed by ICP OES. Lithium solubilization reached ~80% at 90 min, while cobalt extraction was stabilizing at ~79% after 120 min. The enhanced performance under US is attributed to sonochemical effects that promote cavitation and microjets, leading to the disruption of particle agglomerates, the thinning of diffusion layers, and the generation of highly reactive local environments. These processes accelerate deintercalation and mass transfer within the solid–liquid interface. Combined with the mild acidity of DES-FA, which enables simultaneous leaching of both metals while favoring faster kinetics for Li, ultrasound provided a synergistic effect that enhanced the overall process and preserved the distinct extraction profiles of Li and Co. The extraction behavior of the two metals can be explained by their different speciation in the DES-FA medium. Cobalt is likely reduced from Co(III) to Co(II) by formic acid and stabilized through the formation of chloro-complexes such as [CoCl4]2- with chloride anions from ChCl, favoring its solubilization. In contrast, lithium does not form stable complexes with chloride under these conditions. It is primarily extracted as a solvated cation, stabilized by the extensive hydrogen-bond network of the DES. This difference accounts for the faster leaching kinetics observed for Li compared to Co. Selective recovery was achieved by pHcontrolled precipitation, with cobalt oxalate at pH 4-5 and lithium carbonate at pH 10. The Eco-Scale score of 85 confirmed the greenness of the method. This pioneering approach highlights the potential of coupling DES chemistry with ultrasound. Together, they represent a sustainable and efficient route for recovering critical metals from battery waste. T2 - 17th Rio Symposium on Atomic Spectrometry (17th RSAS) CY - São Pedro City, Brazil DA - 09.11.2025 KW - Black mass KW - deep eutectic solvent KW - Lithium KW - Cobalt KW - Lithium-ion battery recycling KW - Ultrasound-assisted extraction KW - Lithium and cobalt recovery KW - Green hydrometallurgy PY - 2025 AN - OPUS4-64956 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tannenberg, Robert T1 - Troponin I Assay in Wafer-Level Backside Optofluidics N2 - Cardiovascular diseases are the number one cause of death worldwide and responsible for 17.9 million casualities worldwide in 2019. Cardiac Troponin I (cTnI) is the most important biomarker for acute events such as heart attacks. The development of novel photonic integrated microchips (PIC) is a promising approach to allow the convenient detection of key biomarkers in complex matrices through multichannel real-time analysis in a highly compact package. This study presents the development and proof-of-concept of a backside released CMOS chip designed for the multichannel real-time detection of biomarkers. In this work, we introduce a Troponin I assay as well that utilizes a potential and practical approach to backside optofluidics on a wafer-level platform. T2 - Biosensors 2025 - 35th Anniversary World Congress on Biosensors CY - Lisbon, Portugal DA - 19.05.2025 KW - Ring resonator KW - Semiconductor KW - CMOS KW - cTnI KW - Heart attack KW - Biomarker KW - Sandwich immunoassay PY - 2025 AN - OPUS4-63481 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Recknagel, Sebastian A1 - Bresch, Harald A1 - Kipphardt, Heinrich A1 - Resch-Genger, Ute A1 - Koch, Matthias A1 - Rosner, M. T1 - Trends in selected fields of reference material production N2 - For more than 110 years, BAM has been producing reference materials for a wide range of application fields. With the development of new analytical methods and new applications as well as continuously emerging more stringent requirements of laboratory accreditation with regard to quality control and metrological traceability, the demand and requirements for reference materials are increasing. This trend article gives an overview of general developments in the field of reference materials as well as developments in selected fields of application in which BAM is active. This includes inorganic and metal analysis, gas analysis, food and consumer products, and geological samples. In addition to these more traditional fields of application, developments in the areas of optical spectroscopy, particulary fluorescence methods, and nanomaterials are considered. T2 - 150 years BAM: Science with impact CY - Berlin, Germany DA - 01.01.2021 KW - Reference material KW - ISO REMCO KW - Gas analysis KW - Food KW - Nanomaterials KW - Fluorescence PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548407 DO - https://doi.org/10.1007/s00216-022-03996-7 SN - 1618-2642 SN - 1618-2650 VL - 414 IS - Topical collection: Analytical methods and applications in the materials and life sciences SP - 4281 EP - 4289 PB - Springer CY - Berlin AN - OPUS4-54840 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hufgard, Josefin T1 - Traveling Wave Acoustic Ion Manipulation (AIM) for Ion Trajectory Alteration N2 - Acoustic ion manipulation (AIM) is a recent discovery reliant on the sound-ion interactions under ambient conditions. Instead of relying upon conventional electric or magnetic fields, this technique initially exploits standing acoustic waves to focus, gate, deflect, and separate ions. Compared to AIM in a standing wave scenario, the transportation of ions and their response to traveling acoustic waves remain less understood. In contrast to standing waves, which establish stationary pressure domains, traveling waves engender continuously propagating pressure variations. Here, we report on AIM effects induced by traveling acoustic waves that occur from a single-transducer setup. The changes in ion trajectory induced by acoustic traveling waves, ion-specific responses to the traveling wave and its analytical applications will be investigated. A home-built alternating-current (AC) plasma source was used to produce a laminar ion stream, positioned ~10 cm from the inlet capillary of an Orbitrap mass spectrometer. A Langevin-type ultrasonic transducer operated at 40 kHz and ~50 W was used to introduce a diverging sound gradient arranged perpendicular to the ion beam direction. Small model analytes, such as methanol, isopropanol, and acetone, were doped in the discharge gas flow as traces produced in the source, to differentiate from ions produced between the source and MS inlet capillary. Aerodynamic information on both the sound field and the gas stream is provided by defocusing shadowgraphy images. T2 - ASMS 73rd Conference on Mass spectrometry and Allied topics CY - Baltimore, Maryland, USA DA - 01.06.2025 KW - Mass spectrometry KW - Acoustic Ion Manipulation (AIM) KW - Traveling acoustic wave PY - 2025 AN - OPUS4-63380 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, Rudolf A1 - He, Y. A1 - Zhu, R. A1 - Cai, Y. A1 - Zhang, Y. A1 - Zhang, Y. A1 - Pan, S. A1 - Zhang, Y. T1 - Transcriptomics and protein biomarkers reveal the detoxifying mechanisms of UV radiation for nebivolol toward zebrafish (Danio rerio) embryos/larvae N2 - Nebivolol (NEB), a β-blocker frequently used to treat cardiovascular diseases, has been widely detected in aquatic environments, and can be degraded under exposure to UV radiation, leading to the formation of certain transformation products (UV-TPs). Thus, the toxic effects of NEB and its UV-TPs on aquatic organisms are of great importance for aquatic ecosystems. In the present study, the degradation pathway of NEB under UV radiation was investigated. Subsequently, zebrafish embryos/larvae were used to assess the median lethal concentration (LC50) of NEB, and to clarify the sub-lethal effects of NEB and its UV-TPs for the first time. It was found that UV radiation could reduce the toxic effects of NEB on the early development of zebrafish. Transcriptomic analysis identified the top 20 enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways in zebrafish larvae exposed to NEB, most of which were associated with the antioxidant, nervous, and immune systems. The number of differentially expressed genes (DEGs) in the pathways were reduced after UV radiation. Furthermore, the analysis of protein biomarkers, including CAT and GST (antioxidant response), AChE and ACh (neurotoxicity), CRP and LYS (immune response), revealed that NEB exposure reduced the activity of these biomarkers, whereas UV radiation could alleviate the effects. The present study provides initial insights into the mechanisms underlying toxic effects of NEB and the detoxification effects of UV radiation on the early development of zebrafish. It highlights the necessity of considering the toxicity of UV-TPs when evaluating the toxicity of emerging pollutants in aquatic systems. KW - Biomarker KW - Pharmazeutika KW - Toxikologie KW - UV Bestrahlung KW - Zebrafisch KW - Transformationsprodukte PY - 2022 DO - https://doi.org/10.1016/j.aquatox.2022.106241 SN - 0166-445X VL - 249 SP - 1 EP - 10 PB - Elsevier CY - Amsterdam AN - OPUS4-55559 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kern, Simon A1 - Liehr, Sascha A1 - Wander, Lukas A1 - Bornemann-Pfeiffer, Martin A1 - Müller, S. A1 - Maiwald, Michael A1 - Kowarik, Stefan T1 - Training data of quantitative online NMR spectroscopy for artificial neural networks N2 - Data set of low-field NMR spectra of continuous synthesis of nitro-4’-methyldiphenylamine (MNDPA). 1H spectra (43 MHz) were recorded as single scans. Two different approaches for the generation of artificial neural networks training data for the prediction of reactant concentrations were used: (i) Training data based on combinations of measured pure component spectra and (ii) Training data based on a spectral model. Synthetic low-field NMR spectra First 4 columns in MAT-files represent component areas of each reactant within the synthetic mixture spectrum. Xi (“pure component spectra dataset”) Xii (“spectral model dataset”) Experimental low-field NMR spectra from MNDPA-Synthesis This data set represents low-field NMR-spectra recorded during continuous synthesis of nitro-4’-methyldiphenylamine (MNDPA). Reference values from high-field NMR results are included. KW - NMR spectroscopy KW - Real-time process monitoring KW - Artificial neural networks KW - Online NMR spectroscopy KW - Automation KW - Process industry PY - 2020 DO - https://doi.org/10.5281/zenodo.3677139 PB - Zenodo CY - Geneva AN - OPUS4-50456 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique T1 - Tracking Lithium-Ion Battery Ageing via Lithium Isotope Fractionation N2 - Lithium-ion batteries power portable devices, electric vehicles, and stationary power grids, yet hidden aging reactions still shorten their service life and raise concerns about cost and safety. An analytical proxy is needed to report these reactions and accelerate product development, quality control, and recycling. Here, we demonstrate that subtle shifts in the natural 7Li/6Li ratio accurately record the two decisive stages of cell aging, solid-electrolyte interphase (SEI) formation and field-driven aging, which can be detected using multi-collector ICP-MS. Because Li is easily stripped from digested electrodes or electrolyte in a one-step cation-exchange column, high-purity solutions reach the spectrometer in minutes. A streamlined MC-ICP-MS run yields a δ7LiLSVEC precision of 0.4 ‰, enabling dozens of battery fractions to be analyzed per day. Applying the workflow to LiCoO2 coin cells as models, sampled from pristine to 700 cycles, reveals a clear isotopic narrative. During the first ≈45 cycles, 7Li leaves the LiCoO2 lattice, dissolves into the electrolyte, and is locked in the SEI on graphite, driving cathode δ7Li from +8 to –10 ‰ and raising the anode to +13 ‰ while capacity drops by 10 %. After the interphase matures, the electric field takes over: the lighter 6Li migrates faster to the anode, 7Li accumulates in the contracting Li1-xCoO2 lattice, and the bulk separation factor rises to α≈1.045 by 700 cycles. The δ7Li curve flattens roughly 70 cycles before capacity falls to 80%, providing an early warning of end-of-life. Isotopic gradients scale linearly with impedance growth, SEI thickness, and crack density confirmed by LA-ICP-MS mapping, FIB-SEM, XANES, and EXAFS. Although each data point requires one cell, lithium-isotope fractionation provides direct, element-specific, and structural fatigue insight unavailable from non-destructive tests. The straightforward chemistry and fast MC-ICP-MS routine make the approach practical for targeted aging studies, additive screening, and forensic autopsies, complementing high-throughput electrochemical methods and supporting the design of longer-lived batteries. T2 - SciX 2025 CY - Covington, KY, USA DA - 05.10.2025 KW - Isotope KW - Lithium KW - MC-ICP-MS KW - MICAP-MS KW - Isotope fractionation KW - Battery PY - 2025 AN - OPUS4-64879 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Plouffe, A. A1 - Lee, R. G. A1 - Byrne, K. A1 - Kjarsgaard, I. M. A1 - Petts, D. C. A1 - Wilton, D.H.C. A1 - Ferbey, T. A1 - Oelze, Marcus T1 - Tracing Detrital Epidote Derived from Alteration Halos to Porphyry Cu Deposits in Glaciated Terrains: The Search for Covered Mineralization N2 - Distal alteration related to porphyry Cu mineralization is typically characterized by an abundance of green minerals, such as epidote, tremolite, and chlorite, within the propylitic and sodic-calcic alteration zones and extends far outside (>1 km) the mineralized zone(s). Glacial erosion and dispersal derived from rocks affected by propylitic and sodic-calcic alteration have resulted in the development of extensive dispersal trains of epidote in till (glacial sediment) that can reach 8 to 330 km2 as observed at four porphyry Cu study sites in the Quesnel terrane of south-central British Columbia: Highland Valley Copper, Gibraltar, Mount Polley, and Woodjam deposits. At each of these sites, epidote is more abundant in heavy mineral concentrates of till collected directly over and down-ice from mineralization and associated alteration. Epidote grains in till with >0.6 ppm Sb and >8 ppm As (as determined by laser ablation-inductively coupled plasma-mass spectrometry) are attributed to a porphyry alteration provenance. There is a greater abundance of epidote grains with high concentrations of trace elements (>12 ppm Cu, >2,700 ppm Mn, >7 ppm Zn, and >37 ppm Pb) in each porphyry district com� pared to background regions. This trace element signature recorded in till epidote grains is heterogeneously distributed in these districts and is interpreted to reflect varying degrees of metal enrichment from a porphyry fluid source. Tracing the source of the epidote in the till (i.e., geochemically tying it to porphyry-related propy� litic and/or sodic-calcic alteration), coupled with porphyry vectoring tools in bedrock, will aid in the detection of concealed porphyry Cu mineralization in glaciated terrains. KW - Indicator minerals KW - Porphyry Cu deposits KW - Epidote KW - Glaciated terrains KW - Propylitic alteration PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-635209 DO - https://doi.org/10.5382/econgeo.5049 SN - 1554-0774 VL - 119 IS - 2 SP - 305 EP - 329 PB - Society of Economic Geologists, Inc. AN - OPUS4-63520 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rodrigues, Leticia T1 - Tracing Copper Fungicide Uptake and Distribution in Pea Plants and Soil Using 65Cu Isotope Labeling N2 - Copper-based fungicides are commonly used in grain farming to prevent yield losses and undesirable changes in organoleptic properties. However, the ingestion of these compounds can pose significant health risks to humans and animals when exposed through the oral route of absorption. To evaluate whether copper from foliar-applied fungicides can be absorbed and translocated to edible plant tissues, this study investigates the mobility of copper from a copper oxychloride fungicide using 65Cu as a stable isotope tracer. A greenhouse system was established to grow peas (Pisum sativum L.) and simulate agricultural fungicide applications. The 65Cu-labeled copper oxychloride fungicide was synthesized in-house and fully characterized by X-ray diffraction (XRD), Raman spectroscopy, and Fourier-transform infrared (FTIR) spectroscopy. Three applications of the fungicide (0,073g of total copper) were performed in a greenhouse pea growing system, while a control system received ultrapure water. After each application, surface soil, pods, and grains were collected, dried, ground, and digested. Total copper concentrations were measured via ICP OES, and 63Cu/65Cu isotopic ratios were analyzed using ICP-MS. Trends in isotopic ratio and total copper accumulation are visualized through the time series below, indicating the fungicide’s mobility and its accumulation in plant tissues and soil. Samples exposed to the copper fungicide exhibited markedly reduced 63Cu/65Cu isotopic ratios, indicating the uptake of the 65Cu tracer. Pod samples from the treated system showed a sharp decrease, especially after the first application. In the control grains, isotopic ratios stayed consistent throughout the experiment, reflecting the absence of direct contact with the fungicide. Conversely, grains from the treated system showed a consistent decrease in isotopic ratio values throughout the three applications. This pattern suggests a possible mechanism for absorbing or transferring copper isotopes from the pods to the grains, indicating the potential for internal contamination of edible plant tissues, even when the fungicide is applied externally. A similar trend was observed in the topsoil: while isotopic ratios remained constant in the control soil, the treated soil showed a consistent decrease after each application. These findings indicate that the copper fungicide is not only absorbed by aerial plant parts but also accumulates in the soil over time. Altogether, the use of 65Cu isotope tracing proved highly effective in assessing the systemic mobility, transfer, and environmental persistence of copper-based fungicides under controlled greenhouse conditions. T2 - 17th Rio Symposium on Atomic Spectrometry (17th RSAS) CY - São Pedro City, Brazil DA - 09.11.2025 KW - Isotope tracer KW - Cu isotopes KW - Copper-based fungicides KW - Soil KW - Food safety KW - Pea plants PY - 2025 AN - OPUS4-64955 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tuma, Dirk T1 - Trace-level ammonia-water interactions in hydrogen: challenges in purity analysis using Optical-Feedback Cavity-Enhanced Absorption Spectroscopy (OF-CEAS) N2 - ISO 14687 defines a threshold of 100 ppb ammonia for hydrogen to be used in fuel cells. This work presents analysis methods using OF-CEAS and discusses moisture-related surface effects on the results. T2 - Gas Analysis 2026 CY - Paris, France DA - 27.01.2026 KW - OF-CEAS KW - Ammonia KW - Moisture effects PY - 2026 AN - OPUS4-65480 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dariz, P. A1 - Schmid, Thomas T1 - Trace compounds in Early Medieval Egyptian blue carry information on provenance, manufacture, application, and ageing N2 - Only a few scientific evidences for the use of Egyptian blue in Early Medieval wall paintings in Central and Southern Europe have been reported so far. The monochrome blue fragment discussed here belongs to the second church building of St. Peter above Gratsch (South Tyrol, Northern Italy, fifth/ sixth century A.D.). Beyond cuprorivaite and carbon black (underpainting), 26 accessory minerals down to trace levels were detected by means of Raman microspectroscopy, providing unprecedented insights into the raw materials blend and conversion reactions during preparation, application, and ageing of the pigment. In conjunction with archaeological evidences for the manufacture of Egyptian blue in Cumae and Liternum and the concordant statements of the antique Roman writers Vitruvius and Pliny the Elder, natural impurities of the quartz sand speak for a pigment produced at the northern Phlegrean Fields (Campania, Southern Italy). Chalcocite (and chalcopyrite) suggest the use of a sulphidic copper ore, and water-insoluble salts a mixed-alkaline flux in the form of plant ash. Not fully reacted quartz crystals partly intergrown with cuprorivaite and only minimal traces of silicate glass portend solid-state reactions predominating the chemical reactions during synthesis, while the melting of the raw materials into glass most likely played a negligible role. KW - Egyptian blue KW - Raman microspectroscopy KW - Spectoscopic imaging KW - Cuprorivaite KW - Amorphous carbon PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537591 DO - https://doi.org/10.1038/s41598-021-90759-6 VL - 11 SP - 1 EP - 12 PB - Nature Portfolio AN - OPUS4-53759 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jaeger, Carsten A1 - Lisec, Jan T1 - Towards Unbiased Evaluation of Ionization Performance in LC-HRMS Metabolomics Method Development N2 - As metabolomics increasingly finds its way from basic science into applied and regulatory environments, analytical demands on nontargeted mass spectrometric detection methods continue to rise. In addition to improved chemical comprehensiveness, current developments aim at enhanced robustness and repeatability to allow long-term, inter-study, and meta-analyses. Comprehensive metabolomics relies on electrospray ionization (ESI) as the most versatile ionization technique, and recent liquid chromatography-high resolution mass spectrometry (LC-HRMS) instrumentation continues to overcome technical limitations that have hindered the adoption of ESI for applications in the past. Still, developing and standardizing nontargeted ESI methods and instrumental setups remains costly in terms of time and required chemicals, as large panels of metabolite standards are needed to reflect biochemical diversity. In this paper, we investigated in how far a nontargeted pilot experiment, consisting only of a few measurements of a test sample dilution series and comprehensive statistical analysis, can replace conventional targeted evaluation procedures. To examine this potential, two instrumental ESI ion source setups were compared, reflecting a common scenario in practical method development. Two types of feature evaluations were performed, (a) summary statistics solely involving feature intensity values, and (b) analyses additionally including chemical interpretation. Results were compared in detail to a targeted evaluation of a large metabolite standard panel. We reflect on the advantages and shortcomings of both strategies in the context of current harmonization initiatives in the metabolomics field. KW - Mass Spectrometry KW - Non-targeted analysis KW - Method development PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548065 DO - https://doi.org/10.3390/metabo12050426 VL - 12 IS - 5 SP - 1 EP - 13 PB - MDPI AN - OPUS4-54806 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klaus, Christian A1 - Soruco Aloisio, Ricardo A1 - Koch, Claudia A1 - Prellwitz, Matthias T1 - Towards Safety and Accuracy of Hydrogen Refuelling Stations through Digital Twins N2 - This paper presents digital quality infrastructure methods for hydrogen refueling stations using the Asset Administration Shell as a standardized digital twin. Implemented at BAM’s test platform, it integrates real-time sensor data, calibration certificates, and compliance documents to support traceable, interoperable asset management. In combination with AI and semantic tools, the system will enable predictive maintenance, remote audits, and improved safety. This approach reduces downtime, enhances transparency, and offers a scalable model demonstrating the potential of digital twins in advancing metrological traceability and operational efficiency in hydrogen technologies. T2 - IMEKO TC-6 International Conference on Metrology and Digital Transformation - M4DConf 2025 CY - Benevento, Italy DA - 03.09.2025 KW - Datenintregration KW - IT KW - Verwaltungsschale KW - Infrastruktur KW - OT KW - Open Source KW - Software PY - 2025 UR - https://www.m4dconf.org/ UR - https://www.sciencedirect.com/journal/measurement-digitalization SP - 1 EP - 6 AN - OPUS4-64951 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Steglich, Patrick A1 - Paul, Martin A1 - Fünning, Tabea A1 - Schumann, Christoph A1 - Mai, Christian A1 - Tannenberg, Robert A1 - Mai, Andreas ED - Cheben, Pavel ED - Čtyroký, Jiří ED - Molina-Fernández, Iñigo T1 - Towards monolithic integration of polymer-based electro-optical devices in silicon photonic integrated circuits using a 250nm SOI technology N2 - Photonic micro-ring resonators (MRR) are widely studied for their high sensitivity across applications like environmental monitoring, healthcare, and chemical analysis. Their evanescent field sensing requires partially unembedded waveguides compatible with CMOS processing. Our approach uses local backside etching with an additional buried oxide (BOX) etch to release waveguides while preserving the back-end of line (BEOL) structure, enabling spatial separation of the sensing area and electronics. The BOX etch critically affects sensor performance, as waveguide surface roughness can alter MRR properties and coupling. We analyzed MRR design variations, comparing wet and dry etching techniques for their effects on optical performance across rib and strip waveguides in quasi-TE and quasi-TM modes. Wafer-level measurements show that backside-released MRR achieve high extinction ratios with slightly reduced quality factors, advancing high-sensitivity photonic sensors. T2 - SPIE Optics + Optoelectronics 2025 CY - Prague, Czech Republic DA - 05.06.2025 KW - Photonic sensors KW - Micro-ring resonator (MRR) KW - Silicon on insulator (SOI) KW - CMOS KW - Local backside etching (LBE) PY - 2025 DO - https://doi.org/10.1117/12.3056280 VL - 13530 SP - 1 EP - 8 PB - SPIE CY - Bellingham, WA , USA AN - OPUS4-63587 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Steglich, Patrick T1 - Towards monolithic integration of polymer-based electro-optical devices in silicon photonic integrated circuits using a 250 nm SOI technology N2 - Silicon-based photonic integrated circuits (PICs) in complementary metal oxide semiconductor (CMOS) technology are essential for next-generation communication systems and neuromorphic computing. However, silicon does not have efficient electro-optical (EO) effects. Since silicon limits the performance of current photonic devices, more advanced materials such as nonlinear optical polymers are needed to exploit the full potential of PICs. As a preliminary proof of concept, we demonstrate the quadratic EO effect and the electric field-induced EO effect using a Mach-Zehnder interferometer in conjunction with a co-integrated Ge photodiode. Our concept of monolithic integration could pave the way for next-generation PICs. T2 - SPIE Optics + Optoelectronics 2025 CY - Prague, Czech Republic DA - 05.06.2025 KW - CMOS KW - Silicon-based photonic integrated circuits KW - Mach-Zehnder interferometer KW - Ge-photodiode PY - 2025 UR - https://www.spiedigitallibrary.org/conference-proceedings-of-spie/13530/135300R/Towards-monolithic-integration-of-polymer-based-electro-optical-devices-in/10.1117/12.3056280.short DO - https://doi.org/10.1117/12.3056280 AN - OPUS4-63569 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hülagü, Deniz A1 - Tobias, Charlie A1 - Gojani, Ardian B. A1 - Rurack, Knut A1 - Hodoroaba, Vasile-Dan T1 - Towards automated scanning electron microscopy image analysis of core-shell microparticles for quasi-3D determination of the surface roughness N2 - Core-shell (CS) particles have been increasingly used for a wide range of applications due to their unique properties by merging individual characteristics of the core and the shell materials. The functionality of the designed particles is strongly influenced by their surface roughness. Quantitative evaluation of the roughness of CS microparticles is, however, a challenging task for Scanning Electron Microscopy (SEM). The SEM images contain two-dimensional (2D) information providing contour roughness data only from the projection of the particle in the horizontal plane. This study presents a practical procedure to achieve more information by tilting the sample holder, hence allowing images of different areas of a single particle to be recorded at different orientations under the same view angle. From the analysis of these images, quasi three-dimensional (3D) information is obtained. Three types of home-made particles were investigated: i) bare polystyrene (PS) particles, ii) PS particles decorated with a first magnetic iron oxide (Fe3O4) nanoparticle shell forming CS microbeads, iii) PS/Fe3O4 particles closed with a second silica (SiO2) shell forming core-shell-shell (CSS) microbeads. A series images of a single particle were taken with stepwise tilted sample holder up to 10° by an SEM with high-resolution and surface sensitive SE-InLens® mode. A reliable analysis tool has been developed by a script in Python to analyze SEM images automatically and to evaluate profile roughness quantitatively, for individual core-shell microparticles. Image analysis consists of segmentation of the images, identifying contour and the centre of the particle, and extracting the root mean squared roughness value (RMS-RQ) of the contour profile from the particle projection within a few seconds. The variation in roughness from batch-to-batch was determined with the purpose to set the method as a routine quality check procedure. Flow cytometry measurements provided complementary data. Measurement uncertainties associated to various particle orientations were also estimated. T2 - ICASS 5th International Conference on Applied Surface Science CY - Palma, Mallorca, Spain DA - 25.04.2022 KW - Core-shell particles KW - Image analysis KW - Roughness KW - Scanning electron microscopy PY - 2022 AN - OPUS4-54774 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rühle, Bastian A1 - Hodoroaba, Vasile-Dan T1 - Towards Automated Electron Microscopy Image Segmentation for Nanoparticles of Complex Shape by Convolutional Neural Networks N2 - In this contribution different ways are explored with the aim to generate suitable training data for ‘non-ideal’ samples using various approaches, e.g., computer-generated images or unsupervised learning algorithms such as generative adversarial networks (GANs). We used these data to train simple CNNs to produce segmentation masks of SEM images and tested the trained networks on real SEM images of complex nanoparticle samples. The novel use of CNN for the automated analysis of the size of nanoparticles of complex shape and with a high degree of agglomeration has proved to be a promising tool for the evaluation of particle size distribution on a large number of constituent particles. Further development and validation of the preliminary model, respectively larger training and validation data sets are necessary. KW - Nanoparticles KW - Convolutional neural networks KW - Image segmentation KW - Electron microscopy KW - Automatisation PY - 2020 DO - https://doi.org/10.1017/S1431927620017262 VL - 26 IS - S2 SP - 1188 EP - 1189 PB - Cambridge University Press CY - Cambridge, UK AN - OPUS4-51773 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Towards automated electron microscopy image segmentation for nanoparticles of complex shape by convolutional neural networks N2 - In this contribution different ways are explored with the aim to generate suitable training data for ‘non-ideal’ samples using various approaches, e.g., computer-generated images or unsupervised learning algorithms such as generative adversarial networks (GANs). We used these data to train simple CNNs to produce segmentation masks of SEM images and tested the trained networks on real SEM images of complex nanoparticle samples. The novel use of CNN for the automated analysis of the size of nanoparticles of complex shape and with a high degree of agglomeration has proved to be a promising tool for the evaluation of particle size distribution on a large number of constituent particles. Further development and validation of the preliminary model, respectively larger training and validation data sets are necessary. T2 - Microscopy and Microanalysis 2020 CY - Online meeting DA - 03.08.2020 KW - Nanoparticles KW - Automatisation KW - Image segmentation KW - Convolutional neural networks KW - Electron microscopy PY - 2020 AN - OPUS4-51114 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grimmer, Christoph A1 - Richter, Matthias A1 - Neuhaus, T. A1 - Prinz, Carsten A1 - Strzelczyk, Rebecca Skadi A1 - Colakoglu, Irem A1 - Horn, Wolfgang T1 - Towards a multi-VOC emission reference material with temporally constant emission profile for QA/QC of materials emission testing procedures N2 - Emission reference materials (ERMs) are sought after to further control and improve indoor air quality. The impregnation of porous materials with volatile organic compounds (VOCs) is a promising approach to produce ERMs. Different VOCs were used to impregnate various porous materials (mainly zeolites, activated carbons and a metal organic framework). The influence of different methodological parameters and material properties were studied to optimize the impregnation procedure and to find the best material/VOC combination. The impregnation procedure remains quite irreproducible, nevertheless, very good ERM candidates were identified. Two materials (zeolite 4 and AC 1 impregnated with n-hexadecane) showed a very stable emission over 14 days (<10 % change). Another material (AC 1 impregnated with toluene) showed a declining emission profile but with a very good in-batch reproducibility and a storage stability of up to 12 months. KW - Emission reference material KW - Porous materials KW - Indoor air quality KW - Emission test chamber KW - CO2 assisted impregnation KW - EN 16516 PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612238 DO - https://doi.org/10.1016/j.chemosphere.2024.143437 SN - 1879-1298 VL - 366 SP - 1 EP - 8 PB - Elsevier AN - OPUS4-61223 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gojani, Ardian T1 - Toward Determination of the Surface Roughness of Particles from a SEM Image N2 - Welcome to the poster Towards Determination of Surface Roughness from a SEM Image, a contribution from BAM in Berlin, Germany. This work is part of the MamaLoCA project, which aims to develop a biosensor for the detection of mycotoxins in cereals. Biosensors come in a great variety, one of which makes use of microscopic beads produced by homogenous coating of polystyrene microspheres. The beads are functionalized by decorating them with bioreceptors – in our case antibodies – which then specifically react with the analyte – in our case mycotoxins – and emit an electrical or optical signal. The functionalization of the beads depends on the surface roughness because this determines the amount and orientation of binders. In other words, the surface roughness affects the accessibility to the binding sites and influences device sensitivity, hence its quantitative determination is an important step in evaluating the quality of the biosensor in general. The presented solution to the problem of the estimation of surface roughness relies in the repetitive characteristics on the surface of the beads. A SEM image of the bead shows a raspberry like microparticle with a variation of grayscale values, which arise from the secondary electron yield. The principle of the measurement measures the variation of grayscale values along a circumference of a circle centred in the centre of the particle and with an arbitrary radius. The grayscale value variation along the given circumference gives the so-called z-modulation or the lateral profile. By performing Fast Fourier Transform on this profile we obtain the power spectrum as a function of the spatial frequencies through which the grayscales vary. The maximal value for spatial frequency then reveals the most common feature along one given circumference. Surface roughness then is the feature frequency in the spatial domain. This calculation is repeated for several concentric circles with different radii over the particle. The results for the same particle but recorded at two different accelerating voltages show that the applied method has a potential to reveal the roughness. Interpretation of results from an SE InLens SEM image obtained using 3 kV shows that surface roughness is about 21 nm, which is in a good agreement with an alternative method given in a different presentation. The results from the 10 kV are underestimated due to the loss of surface sensitivity on the SE InLens detection at high voltages. In conclusion, this method shows promise in determining quantitatively the surface roughness from a single SEM image and its validation is being sought using 3D SEM images and AFM methods. T2 - Microscopy and Microanalysis 2021 CY - Online Meeting DA - 01.08.2021 KW - MamaLoCA KW - Core-shell particles KW - Electron microscopy KW - Image processing KW - Particle characterisation KW - Roughness KW - Fast Fourier Transform PY - 2021 AN - OPUS4-53089 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR ED - Resch-Genger, Ute ED - Koch, Matthias ED - Meermann, Björn ED - Weller, Michael G. T1 - Topical collection: Analytical methods and applications in the materials and life sciences N2 - Current trends in materials and life sciences are flanked by the need to push detection limits to single molecules or single cells, enable the characterization of increasingly complex matrices or sophisticated nanostructures, speed up the time of analysis, reduce instrument complexity and costs, and improve the reliability of data. This requires suitable analytical tools such as spectroscopic, separation and imaging techniques, mass spectrometry, and hyphenated techniques as well as sensors and their adaptation to application-specific challenges in the environmental, food, consumer product, health sector, nanotechnology, and bioanalysis. Increasing concerns about health threatening known or emerging pollutants in drinking water, consumer products, and food and about the safety of nanomaterials led to a new awareness of the importance of analytical sciences. Another important driver in this direction is the increasing demand by legislation, particularly in view of the 17 sustainable development goals by the United Nations addressing clean energy, industry, and innovation, sustainable cities, clean water, and responsible consumption and production. In this respect, also the development of analytical methods that enable the characterization of material flows in production processes and support recycling concepts of precious raw materials becomes more and more relevant. In the future, this will provide the basis for greener production in the chemical industry utilizing recycled or sustainable starting materials. This makes analytical chemistry an essential player in terms of the circular economy helping to increase the sustainability of production processes. In the life sciences sector, products based on proteins, such as therapeutic and diagnostic antibodies, increase in importance. These increasingly biotechnologically produced functional biomolecules pose a high level of complexity of matrix and structural features that can be met only by highly advanced methods for separation, characterization, and detection. In addition, metrological traceability and target definition are still significant challenges for the future, particularly in the life sciences. However, innovative reference materials as required for the health and food sector and the characterization of advanced materials can only be developed when suitable analytical protocols are available. The so-called reproducibility crisis in sciences underlines the importance of improved measures of quality control for all kinds of measurements and material characterization. This calls for thorough method validation concepts, suitable reference materials, and regular interlaboratory comparisons of measurements as well as better training of scientists in analytical sciences. The important contribution of analytical sciences to these developments is highlighted by a broad collection of research papers, trend articles, and critical reviews from these different application fields. Special emphasis is dedicated to often-overlooked quality assurance and reference materials. T2 - 150 years BAM: Science with impact CY - Berlin, Germany DA - 01.01.2021 KW - 150th anniversary KW - ABC KW - Analysis KW - Analytical sciences KW - BAM KW - Collection KW - Environment KW - Fluorescence KW - Life sciences KW - Limit of detection KW - Material sciences KW - Method KW - Nanoparticle KW - Pollutant KW - Quality assurance KW - Reference material KW - Sensor KW - Special issue KW - Bundesanstalt für Materialforschung und -prüfung KW - Jahrestag PY - 2022 UR - https://link.springer.com/journal/216/topicalCollection/AC_16a2ef9b81853377e321ef84d9c4a431 SN - 1618-2642 SN - 1618-2650 VL - 414 SP - 4267 EP - 4529 PB - Springer CY - Berlin AN - OPUS4-55670 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Munir, R. A1 - Lisec, Jan A1 - Swinnen, J. V. A1 - Zaidi, N. T1 - Too complex to fail? Targeting fatty acid metabolism for cancer therapy N2 - Given the central role of fatty acids in cancer pathophysiology, the exploitation of fatty acid metabolism as a potential antineoplastic therapy has gained much attention. Several natural and synthetic compounds targeting fatty acid metabolism were hitherto identified, and their effectiveness against cancer cell proliferation and survival was determined. This review will discuss the most clinically viable inhibitors or drugs targeting various proteins or enzymes mapped on nine interconnected fatty acid metabolism-related processes. We will discuss the general significance of each of these processes and the effects of their inhibition on cancer cell progression. Moreover, their mechanisms of action, limitations, and future perspectives will be assessed. KW - Fatty acids KW - Fatty acid synthesis KW - Fatty acid desaturation KW - Fatty acid uptake KW - Cancer therapy PY - 2022 DO - https://doi.org/10.1016/j.plipres.2021.101143 SN - 0163-7827 VL - 85 SP - 1 EP - 12 PB - Elsevier AN - OPUS4-53864 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Képeš, E. A1 - Gornushkin, Igor B. A1 - Pořízka, P. A1 - Kaiser, J. T1 - Tomography of double-pulse laser-induced plasmas in the orthogonal geometry N2 - The temporal evolution of laser-induced plasmas is studied in the orthogonal double-pulse arrangement. Both the pre-ablation mode (an air spark is induced above the sample surface prior to the ablation pulse) and the re-heating mode (additional energy is delivered into the plasma created by the ablation pulse) is considered. The plasmas are investigated in terms of the temporal evolution of their electron density, temperature, and volume. The plasma volumes are determined using a time-resolved tomography technique based on the Radon transformation. The reconstruction is carried out for both white-light and band-pass filtered emissivities. The white-light reconstruction corresponds to the overall size of the plasmas. On the other hand, the band-pass emissivity reconstruction shows the distribution of the atomic sample species (Cu I). Moreover, through spectrally resolved tomographic reconstruction, the spatial homogeneity of the electron density and temperature of the plasmas is also investigated at various horizontal slices of the plasmas. Our results show that the pre-ablation geometry yields a more temporally stable and spatially uniform plasma, which could be beneficial for calibration-free laser-induced breakdown spectroscopy (LIBS) approaches. On the contrary, the plasma generated in the re-heating geometry exhibits significant variations in electron density and temperature along its vertical axis. Overall, our results shed further light on the mechanisms involved in the LIBS signal enhancement using double-pulse ablation. KW - Laser-induced plasma KW - Laser-induced breakdown spectroscopy KW - Double-pulse laserinduced breakdown spectroscopy KW - Plasma tomography KW - Radon reconstruction PY - 2020 DO - https://doi.org/10.1016/j.aca.2020.06.078 SN - 0003-2670 SN - 0378-4304 VL - 1135 SP - 1 EP - 11 PB - Elsevier CY - Amsterdam AN - OPUS4-51142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Oskoei, Parastu T1 - Thermoresponsive UCNP@MSN Nanoparticles for Doxorubicin Delivery in Melanoma Cells N2 - Upconversion nanoparticles (UCNPs) possess unique photophysical characteristics, such as excita bility by near infrared (NIR) light, which facilitates deep tissue penetration, multi color emission , long luminescence lifetimes, and an excellent photostability. These features have made UCNPs promising tools for biomedical applications . M esoporous silica nanoparticles (MSNs) functionalized with stimuli responsive nanovalves or specific coatings enable the encapsulation and controlled release of therapeutic agen ts, thereby offering spatiotemporal precision in drug delivery 1 3 ]]. Among drug delivery strategies, photoresponsive systems have attracted growing attention due to their potential for clinical applications . This is especially relevant for melanoma, an aggressive skin cancer with increasing global incidence, for which conventional therapeutic modalities remain largely insufficient in advanced stage 4 In this work, core shell UCNP@MSN nanoparticles were synthetised by coating UCNPs with a mesoporous silica layer, which was subsequently functionalized with thermoresponsive retro Diels Alder nanovalves [ and loaded with the chemotherapeutic agent doxorubicin (DOX). Controlled drug release was effectively achieved under 980 nm NIR i llumination . Treatment with functionalized nanoparticles significantly reduced the viability of melanoma cell lines, with an enhanced cytotoxicity being observed upon combined nanoparticle exposure and NIR illumination . Mechanistic analyses revealed that neither UCNPs nor NIR i llumination alone could induce the production of reactive oxygen species (ROS); however, their combination induced a marked increase in ROS levels in two of the three tested cell lines. Furthermore, this dual treatment promoted substantial apoptotic and/or necrotic responses across all cell models. These findings underscore the potential of UCNP@MSN nanoplatforms, equipped with thermoresponsive ga tes , as efficient photoactivated drug delivery systems for melanoma therapy. T2 - Conference Jornadas CICECO CY - Aveiro, Portugal DA - 09.10.2025 KW - Nano KW - Particle KW - Lanthanide KW - Upconversion KW - Surface chemistry KW - Mesoporous silica KW - Doxorubicin KW - Nanomedicine KW - Triggered release KW - pH KW - Cellular uptake KW - Toxicity KW - Folate KW - Ligand PY - 2025 AN - OPUS4-64371 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Scholz, Philipp A1 - Jung, Christian A1 - Weidner, Steffen T1 - Thermo-Desorption Gas Chromatography-Mass Spectrometry for investigating the thermal degradation of polyurethanes N2 - Thermo-Desorption Gas Chromatography-Mass Spectrometry (TD-GC-MS) was used to investigate the thermal degradation of two different polyurethanes (PU). PU samples were heated at different heating rates and the desorbed products were collected in a cold injection system and thereafter submitted to GC-MS. Prospects and limitations of the detection and quantification of semi-volatile degradation products were investigated. A temperature dependent PU depolymerization was found at temperatures above 200 °C proved by an increasing release of 1,4-butanediol and methylene diphenyl diisocyanate (MDI) representing the main building blocks of both polymers. Their release was monitored quantitatively based on external calibration with authentic compounds. Size Exclusion Chromatography (SEC) of the residues obtained after thermodesorption confirmed the initial competitive degradation mechanism indicating an equilibrium of crosslinking and depolymerization as previously suggested. Matrix-Assisted Laser Desorption Ionization (MALDI) mass spectrometry of SEC fractions of thermally degraded PUs provided additional hints on degradation mechanism. KW - Thermo-desorption KW - Mass spectrometry KW - Polyurethanes KW - Thermal degradation PY - 2023 DO - https://doi.org/10.1039/D3AY00173C SN - 1759-9660 SP - 1 EP - 6 PB - Royal Society for Chemistry AN - OPUS4-57307 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zöllner, Moritz T1 - Thermal decomposition of dolomite: Raman spectroscopy as a thermometric tool for the analysis of carbonates in mortar binders. N2 - The reconstruction of the thermal history of minerals is an on-going challenge in the study of anthropogenic materials, e.g., ceramics and mortar binders. For millennia carbonate rocks have been used as the starting material, though the exact manufacturing procedures are often unknown. Preparatory parameters such as firing temperature, heating and cooling rates, soaking time, and kiln atmosphere greatly influence the chemical and structural properties of the resulting products. Analysis of replicas produced under well-defined laboratory conditions help identify indicators for such process parameters and therefore provide valuable insights into historical production workflows. Raman micro-spectroscopy is a valuable method here because of its high sensitivity for crystal-chemical alterations coupled with a high spatial resolution. Previous studies on pyrogenic anhydrite were able to distinguish between gypsum materials that were heated at different temperatures between 400 – 900 °C [1, 2]. The results of thermal experiments with natural dolomite powder between 500 – 900 °C are presented, evaluating the thermal decomposition of dolomite and the consequent formation of calcium carbonate. Raman measurements were performed at room temperature on calcinated samples, as well as subsequently hydrated and re-carbonated samples. A peak-fitting routine using python scripts was employed to extract the peak positions and the full width at half maximum (FWHM) values of the ν1-, ν4- and L-bands of the carbonates. The results reveal the formation of Mg-calcite from dolomite at 700 – 750 °C and the formation of Mg-free calcite after calcination above 750 °C and subsequent hydration and re-carbonation. The findings from the thermal experiments are compared with Raman-microscopy mappings on medieval and reenacted mortars containing dolomite. Mg-calcite with comparable peak position and FWHM values have been successfully identified, proving Raman spectroscopy to be a suitable tool for elucidating the manufacturing procedures of anthropogenic materials. T2 - European Mineralogical Conference 2024 CY - Dublin, Ireland DA - 18.08.2024 KW - Raman spectroscopy KW - Dolomite KW - Mineral thermometry PY - 2024 AN - OPUS4-61975 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zöllner, Moritz T1 - Thermal decomposition of dolomite: Raman spectroscopy as a thermometric tool for the analysis of carbonates in mortar binders. N2 - High-spectral resolution Raman spectroscopy is a powerful tool for the chemical and structural analysis in material sciences. Beyond its usage for the qualitative identification of minerals, Raman spectroscopy has been applied for the quantitative characterisation of chemical phases. The precise measurement of Raman peak position and band width values allows for an empirical differentiation of chemically similar phases and thus provides valuable insights to the structural properties of a material. In the field of archaeometry, the crystal structure of minerals can be used to elucidate the preparatory parameters of historical samples, such as the firing temperature. Comparison of historical materials with replicas produced under well-defined laboratory conditions help identify indicators for such process parameters. Previous Raman studies on pyrogenic anhydrite were able to distinguish between gypsum materials that were heated at different temperatures between 400–900 °C [1–3]. The results of thermal experiments with natural dolomite powder between 500–900 °C are presented, evaluating the thermal decomposition of dolomite and the consequent formation of calcium carbonate. Raman measurements were performed with excitation at 532 nm and 1800 mm-1 grating at room temperature on calcinated samples, as well as subsequently hydrated and re-carbonated samples. These high-resolution conditions are necessary to resolve the individual spectral contributions of different calcium/magnesium carbonate species. However, this sensitivity does not come without potential pitfalls. While the usage of micro-Raman spectroscopy with high spectral resolution shows great promise for evaluating minor shifts in peak positions and band widths, several technical aspects must be considered. For example, great care must be taken to exclude the thermal impact of the highly focused Raman laser on the sample. Similarly, exact standard operating procedures have to be followed to circumvent mechanical hysteresis in the alignment of the spectrographs’ grating. The influence of these two effects is presented and effective countermeasures are introduced to avoid resulting systematic errors. Statistical reliability and chemical imaging both rely on the individual analysis of thousands of Raman spectra. Thus, besides the spectral acquisition, also highly automated data analysis must be applied. Therefore, a peak-fitting routine using python scripts was employed to extract the peak positions and the full width at half maximum (FWHM) values of the ν1-, ν4- and L-bands of the carbonates. The results reveal the formation of Mg-calcite from dolomite at 700–750 °C and the formation of Mg-free calcite after calcination above 750 °C and subsequent hydration and re-carbonation (Fig. 1a). The findings from the thermal experiments are compared with Raman-microscopy mappings on medieval and reenacted mortars containing dolomite. Mg-calcite with comparable peak position and FWHM values have been successfully identified (Fig. 1b), proving Raman spectroscopy to be a suitable tool for elucidating the manufacturing procedures of anthropogenic materials. T2 - 16th GeoRAMAN Conference CY - Rhodes, Greece DA - 24.09.2024 KW - Raman spectroscopy KW - Dolomite KW - Mineral thermometry PY - 2024 AN - OPUS4-61977 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zöllner, Moritz T1 - Thermal decomposition of dolomite: Raman spectroscopy as a thermometric tool for the analysis of carbonates in mortar binders N2 - The reconstruction of the thermal history of minerals is an on-going challenge in the study of anthropogenic materials, e.g., ceramics and mortar binders. For millennia carbonate rocks have been used as the starting material, though the exact manufacturing procedures are often unknown. Preparatory parameters such as firing temperature, heating and cooling rates, soaking time, and kiln atmosphere greatly influence the chemical and structural properties of the resulting products. Analysis of replicas produced under well-defined laboratory conditions help identify indicators for such process parameters and therefore provide valuable insights into historical production workflows. Raman micro-spectroscopy is a valuable method here because of its high sensitivity for crystal-chemical alterations coupled with a high spatial resolution. Previous studies on pyrogenic anhydrite were able to distinguish between gypsum materials that were heated at different temperatures between 400–900 °C [1-3]. The results of thermal experiments with natural dolomite powder between 500–900 °C are presented, evaluating the thermal decomposition of dolomite and the consequent formation of calcium carbonate. Raman measurements were performed at room temperature on calcinated samples, as well as subsequently hydrated and re-carbonated samples. Raman band positions and the full width at half maximum (FWHM) values of the ν1-, ν4- and L-bands of the carbonates are extracted and reveal the formation of Mg-calcite from dolomite at 700–750 °C and the formation of Mg-free calcite after calcination above 750 °C and subsequent hydration and re-carbonation. The findings from the thermal experiments are compared with Raman-microscopy mappings on medieval and reenacted mortars containing dolomite. Mg-calcite with comparable peak position and FWHM values have been successfully identified, proving Raman spectroscopy to be a suitable tool for elucidating the manufacturing procedures of anthropogenic materials. T2 - SciX 2024 CY - Raleigh, NC, USA DA - 20.10.2024 KW - Raman spectroscopy KW - Dolomite KW - Mineral thermometry PY - 2024 AN - OPUS4-61978 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique T1 - The use of reference materials to improve the calibration strategy in glow discharge optical emission spectroscopy with machine learning N2 - Glow discharge optical emission spectroscopy (GD-OES) is a technique for the analysis of solids such as metals, semiconductors, and ceramics. A low-pressure glow discharge plasma is applied in this system, which ‘sputters’ and promotes the sample atoms to a higher energy state. When the atoms return to their ground state, they emit light with characteristic wavelengths, which a spectrometer can detect. Thus, GD-OES combines the advantages of ICP-OES with solid sampling techniques, which enables it to determine the bulk elemental composition and depth profiles. However, direct solid sampling methods such as glow-discharge spectroscopy require reference materials for calibration due to the strong matrix effect. Reference materials are essential when the accuracy and reliability of measurement results need to be guaranteed to generate confidence in the analysis. These materials are frequently used to determine measurement uncertainty, validate methods, suitability testing, and quality assurance. In addition, they guarantee that measurement results can be compared to recognized reference values. Unfortunately, the availability of certified reference materials suited to calibrate all elements in different matrix materials is limited. Therefore various calibration strategies and the preparation of traceable matrix-matched calibration standards will be discussed. Machine learning is an essential component of the growing field of data science. Through statistical methods, algorithms are trained to make classifications or predictions, uncovering key insights within data mining projects. Therefore, it was tried in our work to combine GD-OES with machine learning strategies to establish a new and robust calibration model, which can be used to identify the elemental composition and concentration of metals from a single spectrum. For this purpose, copper reference materials from different manufacturers, which contain various impurity elements, were investigated using GD-OES. The obtained spectra information are evaluated with different algorithms (e.g., gradient boosting and artificial neural networks), and the results are compared and discussed in detail. T2 - Winter Conference on Plasma Chemistry 2022 CY - Tucson, AZ, USA DA - 17.01.2022 KW - GDOES KW - Machine learning KW - Reference materials KW - Calibration KW - Cooper PY - 2022 AN - OPUS4-56497 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pramann, A. A1 - Vogl, Jochen A1 - Rienitz, O. T1 - The Uncertainty Paradox: Molar Mass of Enriched Versus Natural Silicon Used in the XRCD Method N2 - The X-ray crystal density method uses silicon spheres highly enriched in 28Si as a primary method for the dissemination of the SI base unit kilogram yielding smallest possible uncertainties associated with the mass m within a few parts in 10-8. This study compares different available and newly developed analytical methods and their results for the determination of the molar mass M of silicon highly enriched in 28Si (Me) and of silicon (Mx) with an almost natural isotopic distribution. While for Me relative uncertainties urel(Me) in the lower 10-9 range are obtained routinely, it was not possible to fall below a value of urel(Mx) < 4 x 10-6 in the case of natural silicon, which is approximately three orders of magnitude larger. The application of the state-of the-art isotope ratio mass spectrometry accompanied with sophisticated thoroughly investigated methods suggests an intrinsic cause for the large uncertainty associated with the molar mass of natural silicon compared to the enriched material. KW - silicon KW - Molar mass KW - Isotope ratios KW - SI KW - Kilogram KW - Mole KW - XRCD method PY - 2020 DO - https://doi.org/10.1007/s12647-020-00408-y VL - 35 SP - 499 EP - 510 PB - Springer Verlag AN - OPUS4-51637 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogl, Jochen T1 - The triple-isotope calibration approach: a universal and standard-free calibration approach for obtaining absolute isotope ratios of multi-isotopic elements N2 - The theory of a new calibration approach for obtaining absolute isotope ratios of multi-isotopic elements without the use of any standard has been developed. The calibration approach basically uses the difference in the instrumental isotope fractionation of two different types of mass spectrometers, leading to two different fractionation lines in a three-isotope diagram. When measuring the same sample with both mass spectrometers, the different fractionation lines have one point in common: this is the ‘true’ logarithmized isotope ratio pair of the sample. Thus, the intersection of both fractionation lines provides us with the absolute isotope ratios of the sample. This theory has been tested in practice by measuring Cd and of Pb isotope ratios in the certified reference materials BAM-I012 and NIST SRM981 by thermal ionization mass spectrometry and by inductively coupled plasma mass spectrometry while varying the ionization conditions for both mass spectrometers. With this experiment, the theory could be verified, and absolute isotope ratios were obtained, which were metrologically compatible with the certified isotope ratios. The so-obtained absolute isotope ratios are biased by − 0.5% in average, which should be improved with further developments of the method. This calibration approach is universal, as it can be applied to all elements with three or more isotopes and it is not limited to the type of mass spectrometers applied; it can be applied as well to secondary ion mass spectrometry or others. Additionally, this approach provides information on the fractionation process itself via the triple-isotope fractionation exponent θ. KW - Triple isotope fractionation KW - Absolute isotope ratio KW - Mass spectrometry KW - Calibration KW - Uncertainty PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-516364 DO - https://doi.org/10.1007/s00216-020-03050-4 VL - 413 IS - 3 SP - 821 EP - 826 PB - Springer Verlag AN - OPUS4-51636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogl, Jochen T1 - The triple isotope calibration approach BT - A new calibration approach for obtaining absolute isotope ratios of multi-isotopic elements N2 - The calibration of isotope ratio measurements is an ongoing challenge since instrumental isotope fractionation (IIF) has been detected in mass spectrometry (MS). There is a variety of approaches which either bypass IIF such as delta measurements or refer to reference materials (RMs) and thus shifting the problem of calibration to somebody else: the RM producer. For certifying isotope RMs with absolute isotope ratios only a few approaches are available, namely the isotope mixture approach, the double spike approach, the mass bias regression model and total evaporation in TIMS. All of them require either enriched isotopes, isotope RMs of another element or an RM for correcting residual error. As the enriched isotopes required for the isotope mixture and the double spike approach need to be fully characterized beforehand, all mentioned calibration approaches require a standard. Here, a new and standard-free calibration approach for obtaining absolute isotope ratios of multi-isotopic elements has been developed. The underlying principle is that each MS suffers from IIF and thus yields a specific isotope fractionation line in a three-isotope diagram. When applying a second MS featuring a different ionization mechanism, we obtain a second isotope fractionation line with a different slope in the same three-isotope diagram. In both cases the absolute isotope ratios range somewhere on the isotope fractionation line. Consequentially, the intersect of both lines yield the absolute isotope ratios of the measured sample. This theory has been tested by measuring Cd and Pb isotope ratios of suitable isotope RMs with a TIMS and an ICP-MS, both equipped with multi-collector array. During the measurements the ionization conditions were changed such that different extent of the isotope fractionation has been achieved. With the resulting data set the theory described above could be verified. The obtained absolute isotope ratios were metrologically compatible with the certified isotope ratios. The remaining average bias of -5 ‰ can be reduced with further improvements. The calibration approach is universal and can be applied to any multi-isotopic element and it is not limited by the type of the mass spectrometer. T2 - Virtual Goldschmidt 2021 CY - Online meeting DA - 04.07.2021 KW - Absolute isotope ratio KW - Traceability KW - Metrology KW - Calibration KW - Uncertainty KW - Triple isotope fractionation PY - 2021 AN - OPUS4-53023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Coplen, T. B. A1 - Holden, N. E. A1 - Ding, T. A1 - Meijer, H. A. J. A1 - Vogl, Jochen A1 - Zhu, X. T1 - The Table of Standard Atomic Weights—An exercise in consensus N2 - The present Table of Standard Atomic Weights (TSAW) of the elements is perhaps one of the most familiar data sets in science. Unlike most parameters in physical science whose values and uncertainties are evaluated using the “Guide to the Expression of Uncertainty in Measurement” (GUM), the majority of standard atomic weight values and their uncertainties are consensus values, not GUM-evaluated values. The Commission on Isotopic Abundances and Atomic Weights of the International Union of Pure and Applied Chemistry (IUPAC) regularly evaluates the literature for new isotopic-abundance measurements that can lead to revised standard atomic-weight values, Ar(E) for element E. The Commission strives to provide utmost clarity in products it disseminates, namely the TSAW and the Table of Isotopic Compositions of the Elements (TICE). In 2016, the Commission recognized that a guideline recommending the expression of uncertainty listed in parentheses following the standard atomic-weight value, for example, Ar(Se) = 78.971(8), did not agree with the GUM, which suggests that this parenthetic notation be reserved to express standard uncertainty, not the expanded uncertainty used in the TSAW and TICE. In 2017, to eliminate this noncompliance with the GUM, a new format was adopted in which the uncertainty value is specified by the “±” symbol, for example, Ar(Se) = 78.971 ± 0.008. To clarify the definition of uncertainty, a new footnote has been added to the TSAW. This footnote emphasizes that an atomic-weight uncertainty is a consensus (decisional) uncertainty. Not only has the Commission shielded users of the TSAW and TICE from unreliable measurements that appear in the literature as a result of unduly small uncertainties, but the aim of IUPAC has been fulfilled by which any scientist, taking any natural sample from commerce or research, can expect the sample atomic weight to lie within Ar(E) ± its uncertainty almost all of the time. KW - Atomic weight KW - Standard atomic weight KW - Uncertainty PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551299 DO - https://doi.org/10.1002/rcm.8864 SN - 1097-0231 VL - 36 IS - 15 SP - 1 EP - 15 PB - Wiley AN - OPUS4-55129 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cheng, Z. A1 - Meng, M. A1 - Qiao, X. A1 - Liu, Y. A1 - Resch-Genger, Ute A1 - Ou, J. T1 - The synthesis of Er3+/Yb3+/K+ triple-doped NaYF4 phosphors and its high sensitivity optical thermometers at low power N2 - Optical Thermometry is popular among researchers because of its non-contact, high sensitivity, and fast measurement properties. In the present experiment, Er3+/Yb3+/K+ co-doped NaYF4 nanoparticles with different K+ concentrations were synthesized by solvothermal method, and the samples showed bright upconversion green emission under the excitation of a 980 nm laser. The powder X-ray diffractometer and transmission electron microscope were used to characterize the crystal structure and its surface morphology, respectively. The spectral characteristics of nanoparticles with K+ doping concentration from 10% to 30% (Molar ratio) were investigated by fluorescence spectroscopy, and it was observed that the fluorescence intensity reached the maximum at the K+ concentration of 20%, after which the intensity weakened when the K+ content continued to increase. According to the dependence between the luminescence intensity of the sample and the laser power density and fluorescence lifetime, the intrinsic mechanism was carefully investigated. Temperature-dependent spectra of the samples were recorded in the temperature range of 315–495 K, and the maximum values of absolute sensitivity (Sa) and relative sensitivity (Sr) were measured at 0.0041 K−1 (455 K) and 0.9220%K−1 (315 K). The experimental results show that K+/Er3+/Yb3+ triple-doped NaYF4 green fluorescent nanoparticles (GFNs) have good prospects for applications in display devices, temperature sensing, and other fields. KW - K+ doped KW - Upconversion luminescence KW - Optical temperature sensing KW - Thermal coupling energy level PY - 2023 DO - https://doi.org/10.1016/j.jallcom.2022.168299 VL - 937 SP - 1 EP - 9 PB - Elsevier B.V. AN - OPUS4-57106 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - The SMURFnano project - standardized measurements of surface functionalities on nanoparticles N2 - Engineered nanoparticles (NPs) with various chemical compositions and surface functionalities are routinely fabricated for industrial applications such as medical diagnostics, drug delivery, sensing, catalysis, energy conversion and storage, optoelectronics, and information storage. NP function, interaction with biological species, and environmental fate are largely determined by surface functionalities. Reliable, reproducible, and standardized surface characterization methods are therefore vital for quality control of NPs, and mandatory to meet increasing concerns regarding their safety. Also, industry, international standardization organizations, regulatory agencies, and policymakers need validated and standardized measurement methods and reference materials. However, methodologies for determining NP surface properties, including the amount, chemical composition, and homogeneity of surface functionalities and coatings are largely non-standardized. Suitable methods for determining surface functionalities on ligand-stabilized core and core/shell NPs include advanced techniques such as traceable quantitative nuclear magnetic resonance (qNMR) as well as X-ray electron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF-SIMS), and simpler optical and electrochemical methods. The latter less costly methods are often used by SMEs, e.g., for quality control. To validate methods, establish measurement uncertainties, test reference materials, and produce reference data, international interlaboratory comparisons (ILC) on NP surface functionalization measurements are required and well characterized test and reference nanomaterials providing benchmark values.[1] These needs are addressed by the recently started European metrology project SMURFnano involving 12 partners from different National Metrology Institutes, designated institutes, and research institutes, two university groups as well as one large company and one SME producing NPs. This project as well as first results derived from the development of test and reference materials with a well characterized surface chemistry and ongoing interlaboratory comparisons will be presented. T2 - eMRS CY - Strasbourg, France DA - 27.05.2025 KW - Quality assurance KW - Reference analysis KW - Standardization KW - Metrology KW - Reference products KW - Reference materials KW - Mission KW - Surface chemistry KW - Nano KW - Particle KW - qNMR KW - XPS KW - Fluorescence KW - Optical assays KW - Interlaboratory comparison KW - Uncertainty PY - 2025 AN - OPUS4-63243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, P. A1 - Morales-Marquez, R. A1 - Cervas, G. A1 - Hernandez Medel, A. A1 - Ogayar, M. P. A1 - Jimenez de Aberasturi, D. A1 - de Isidro-Gomez, A. I. A1 - Torres-Padro, A. A1 - Palomares, F. J. A1 - Garcia-Orrit, S. A1 - Sousa, C. T. A1 - Espinosa, A. A1 - Telle, H. H. A1 - Ortgies, D. H. A1 - Vega-Mayoral, V. A1 - Cabanillas-Gonzalez, J. A1 - Rodriguez, E. M. A1 - Resch-Genger, Ute A1 - Wegner, Karl David A1 - Juarez, B. H. T1 - The role of temperature in the photoluminescence quantum yield (PLQY) of Ag2S-based nanocrystals N2 - Highly emissive Ag2S nanocrystals (NCs) passivated with a gradated shell incorporating Se and Zn were synthesized in air, and the temperature dependence of their photoluminescence quantum yield (PLQY) was quantified in both organic and aqueous media at B1200 nm. The relevance of this parameter, measured at physiological temperatures, is highlighted for applications that rely on the near infrared (NIR) photoluminescence of NCs, such as deep NIR imaging or luminescence nanothermometry. Hyperspectral NIR imaging shows that Ag2S-based NCs with a PLQY in organic media of about 10% are inefficient for imaging at 40 8C through 20 mm thick tissue with low laser irradiation power densities. In contrast, water-transferred Ag2S-based NCs with an initial PLQY of 2% in water exhibit improved robustness against temperature changes, enabling improved imaging performance. KW - Quantum dots KW - Ag2S KW - Fluorescence KW - Nanomaterial design KW - Advanced nanomaterials KW - Shortwave infrared (SWIR) KW - Temperature sensing PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613877 DO - https://doi.org/10.1039/D4MH01016G SP - 1 EP - 11 PB - Royal Society of Chemistry (RSC) AN - OPUS4-61387 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weller, Michael G. T1 - The Protocol Gap N2 - Although peer review is considered one of the main pillars of modern science, experimental methods and protocols seem to be not a rigorous subject of this process in many papers. Commercial equipment, test kits, labeling kits, previously published concepts, and standard protocols are often considered to be not worth a detailed description or validation. Even more disturbing is the extremely biased citation behavior in this context, which sometimes leads to surrogate citations to avoid low-impact journals, preprints, or to indicate traditional practices. This article describes some of these surprising habits and suggests some measures to avoid the most unpleasant effects, which in the long term may undermine the credibility of science as a whole. KW - Validation KW - Peer review KW - Experiment KW - Documentation KW - Scientific publication KW - Reproducibility crisis KW - Replication crisis KW - Trust KW - Citation KW - References KW - Surrogate citations KW - Impact PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521440 DO - https://doi.org/10.3390/mps4010012 SN - 2409-9279 VL - 4 IS - 1 SP - 1 EP - 5 PB - MDPI CY - Basel AN - OPUS4-52144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Billimoria, K. A1 - Diaz Fernandez, Y. A. A1 - Andresen, Elina A1 - Sorzabal-Bellido, I. A1 - Huelga-Suarez, G. A1 - Bartczak, D. A1 - Ortiz de Solórzano, C. A1 - Resch-Genger, Ute A1 - Goenaga Infante, H. T1 - The potential of bioprinting for preparation of nanoparticle-based calibration standards for LA-ICP-ToF-MS quantitative imaging N2 - This paper discusses the feasibility of a novel strategy based on the combination of bioprinting nano-doping technology and laser ablation-inductively coupled plasma time-of-flight mass spectrometry analysis for the preparation and characterization of gelatin- based multi-element calibration standards suitable for quantitative imaging. To achieve this, lanthanide up-conversion nanoparticles were added to a gelatin matrix to produce the bioprinted calibration standards. The features of this bioprinting approach were com- pared with manual cryosectioning standard preparation, in terms of throughput, between batch repeatability and elemental signal homogeneity at 5 μm spatial resolution. By using bioprinting, the between batch variability for three independent standards of the same concentration of 89 Y (range 0–600 mg/kg) was reduced to 5% compared to up to 27% for cryosectioning. On this basis, the relative standard deviation ( RSD ) obtained between three independent calibration slopes measured within 1 day also reduced from 16% (using cryosectioning ) to 5% (using bioprinting), supporting the use of a single standard preparation replicate for each of the concentrations to achieve good calibration performance using bioprinting. This helped reduce the analysis time by approximately 3-fold. With cryosectioning each standard was prepared and sectioned individually, whereas using bio-printing it was possible to have up to six different standards printed simultaneously, reducing the preparation time from approximately 2 h to under 20 min (by approxi- mately 6-fold). The bio-printed calibration standards were found stable for a period of 2 months when stored at ambient temperature and in the dark. KW - Environmental analysis KW - LA-ICP-MS KW - Lanthanide KW - Tag KW - Fluorescence KW - Nanoparticles KW - Reference material KW - Quality assurance KW - 3D-printing KW - Synthesis KW - Production KW - Multimodal PY - 2022 DO - https://doi.org/10.1093/mtomcs/mfac088 SN - 1756-591X VL - 14 IS - 12 SP - 1 EP - 9 PB - Oxford University Press CY - Oxford AN - OPUS4-57018 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maiwald, Michael T1 - The internet of things in the lab and in process - The digital transformation challenges for the laboratory 4.0 T1 - Das Internet of Things in Labor und Prozess - Herausforderungen des digitalen Wandels für das Labor 4.0 N2 - It is a fact that much of the time spent on analytical laboratory instrumentation these days goes into system maintenance. Digital transformation could give us more time again for creativity and our actual laboratory work – if we shape it the right way. N2 - Fakt ist: Einen Großteil der Zeit, der an analytischen Laborgeräten verbracht wird, nimmt heute die Systempflege in Anspruch. Der digitale Wandel kann uns endlich wieder mehr Zeit für Kreativität und die eigentliche Laborarbeit geben – wenn wir ihn richtig gestalten. KW - Lab of the Future KW - Digitalisation KW - Automation KW - Data Analysis KW - Instrument Communication KW - Labor der Zukunft KW - Digitale Transformation KW - Automatisierung KW - Gerätekommunikation PY - 2020 IS - 4 SP - 1 EP - 3 PB - Lumitos AG CY - Darmstadt AN - OPUS4-50618 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meermann, Björn T1 - The future of elemental analytical chemistry – the sixth special issue dedicated to young analytical scientists N2 - Editorial for a special issue KW - Editorial KW - Special issue, young analytical scientists KW - Elemental analysis PY - 2021 DO - https://doi.org/10.1039/d1ja90038b VL - 36 IS - 9 SP - 1794 EP - 1796 PB - RSC AN - OPUS4-53086 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ecke, Alexander T1 - The Fate of the Antibiotic Amoxicillin in the Aquatic Environment N2 - Contamination of the environment with antibiotics is of great concern as it promotes the evolution of antimicrobial resistances. In case of amoxicillin (AMX) in the aquatic environment, further risk arises from hydrolysis products (HPs) which can cause allergy. To assess these risks, a comprehensive investigation and understanding of the degradation of AMX is necessary. We investigated the hydrolysis rate of AMX in different types of water as well as the influence of temperature and irradiation. The content of the heavy metal ions copper and zinc was found to be crucial for the hydrolysis rate of AMX and stability of HPs. Eventually, a new degradation pathway for AMX could be elaborated and confirmed by tandem mass spectrometry (LC-MS/MS). T2 - Berliner Chemie in Praxis Symposium CY - Berlin, Germany DA - 07.10.2022 KW - Hydrolysis KW - Amoxicillin KW - LC-MS/MS KW - ICP-MS PY - 2022 AN - OPUS4-56026 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chronakis, Michail Ioannis A1 - Meermann, Björn A1 - von der Au, Marcus T1 - The evolution of data treatment tools in single-particle and single-cell ICP-MS analytics N2 - Single-particle inductively coupled plasma-mass spectrometry (sp-ICP-MS) is one of the most powerful tools in the thriving field of nanomaterial analysis. Along the same lines, single-cell ICP-MS (sc-ICP-MS) has become an invaluable tool in the study of the variances of cell populations down to a per-cell basis. Their importance and application fields have been listed numerous times, across various reports and reviews. However, not enough attention has been paid to the immense and ongoing development of the tools that are currently available to the analytical community for the acquisition, and more importantly, the treatment of single-particle and single-cell-related data. Due to the ever-increasing demands of modern research, the efficient and dependable treatment of the data has become more important than ever. In addition, the field of single-particle and single-cell analysis suffers due to a large number of approaches for the generated data—with varying levels of specificity and applicability. As a result, finding the appropriate tool or approach, or even comparing results, can be challenging. This article will attempt to bridge these gaps, by covering the evolution and current state of the tools at the disposal of sp-ICP-MS users. Graphical Abstract KW - Trend Article KW - spICP-MS KW - Data Tools KW - scICP-MS PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610539 DO - https://doi.org/10.1007/s00216-024-05513-4 SP - 1 EP - 7 PB - Springer Science and Business Media LLC AN - OPUS4-61053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - The emp project smurfnano – Standardizing the quantification of surface functionalities, ligands, and coatings on nanomaterials N2 - For industrial applications such as medical diagnostics, drug delivery, sensing, catalysis, energy conversion and storage, opto-electronics, and information storage, meanwhile engineered nanoparticles (NPs) with various chemical compositions and surface functionalities are routinely fabricated. NP function, interaction with biological species, and environmental fate are largely determined by surface functionalities. Reliable, reproducible, and standardized surface characterization methods are therefore vital for quality control of NPs, and mandatory to meet increasing concerns regarding their safety. Also, industry, international standardization organizations, regulatory agencies, and policymakers need validated and standardized measurement methods and reference materials. These needs are addressed by the recently started European metrology project SMURFnano involving 12 partners from different National Metrology Institutes, designated institutes, and research institutes, two university groups as well as one large company and one SME producing NPs. This project as well as first results derived from the development of test and reference materials with a well characterized surface chemistry and ongoing interlaboratory comparisons will be presented. T2 - LNE Workshop CY - Paris, France DA - 04.11.2025 KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Synthesis KW - Characterization KW - Advanced material KW - Surface KW - Standardization KW - Reference material KW - Functional group KW - Quantification KW - Coating KW - Automation KW - Potentiometry KW - Method KW - Validation KW - Optical assay KW - Fluram KW - qNMR KW - Comparison KW - ILC PY - 2025 AN - OPUS4-64725 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Palásti, Dávid jenö T1 - The effects of the laser pulse profile on the plasma emission properties N2 - Intense laser pulses create plasmas upon radiation on targets, and the properties of such plasmas are generally determined by both the properties of the target and the laser pulse. In terms of laser intensity, the irradiance and even more importantly the fluence are the critical parameters [1]. Since most lasers emit pulses of a constant pulse duration dictated by the design of the resonator and Q-switch, these two parameters are usually used interchangeably in studies. However, with the emergence of fiber laser based light sources [2], which are capable not just to freely tune the pulse duration, but to generate variable and high pulse repetition rates, up to the MHz range, a new and interesting optimization aspect is given to the laser spectroscopy community. In our study a low alloy steel standard sample (BAS 403/1) was investigated using a variable pulse duration and pulse repetition rate MOPA laser with 80W power of  = 1064 nm emission (JPT M7, VONJAN Technology GmbH, Wessling, Germany). In our experiments the laser was set to pulses with low individual energy (0.4 mJ) at 200 kHz pulse repetition rate, while the pulse duration was varied between 50 and 500 ns. The plasma emission was recorded by an LTB Demon spectrometer in several spectral regions, which included iron, chromium and manganese lines. Utilizing the variable pulse duration of this laser source, it was possible to assess the effects of changing the fluence, while the irradiance was kept at the same value. Among the investigated parameters are the emission intensity, peak width and self-absorption characteristics of major and minor components, as well as the plasma temperature. While the effects for the peak intensity are quite well correlated with the fluence, its interplay with other peak parameters appear to be more complicated. T2 - AMACEE 2025 CY - Brno, Czech Republic DA - 26.08.2025 KW - LIBS KW - Fiberlaser KW - Plasma properties PY - 2025 AN - OPUS4-64218 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rienitz, O. A1 - Pramann, A. A1 - Vogl, Jochen A1 - Lee, K.-S. A1 - Yim, Y.-H. A1 - Malinovskiy, D. A1 - Hill, S. A1 - Dunn, P. A1 - Goenaga-Infante, H. A1 - Ren, T. A1 - Wang, J. A1 - Vocke jr., R. D. A1 - Rabb, S: A. A1 - Narukawa, T. A1 - Yang, L. A1 - Mester, Z. A1 - Meija, J. A1 - Aref'ev, D. G. A1 - Marchin, V. A1 - Sharin, A. G. A1 - Bulanov, A. D. A1 - Potapov, A. M. A1 - Otopkova, P. A. A1 - Kessel, R. T1 - The comparability of the determination of the molar mass of silicon highly enriched in 28Si: results of the CCQM-P160 interlaboratory comparison and additional external measurements N2 - An international comparison study on the accurate determination of the molar mass M(Si) of silicon artificially enriched in 28Si (x(28Si) > 0.9999 mol mol−1) has been completed. The measurements were part of the high level CCQM-P160 pilot study assessing the ability of National Metrology Institutes (NMIs) and Designated Institutes (DIs) to make such measurements at the lowest possible levels of measurement uncertainty and to identify possible difficulties when measuring this kind of sample. This study supports the molar mass measurements critical to disseminating the silicon route to realizing the new definitions for the kilogram and the mole. Measurements were also made by one external research institute and an external company. The different institutes were free to choose their experimental (mass spectrometric) set-ups and equipment, thereby enabling also the comparison of different techniques. The investigated material was a chemically pure, polycrystalline silicon material. The subsequent modified single crystalline secondary product of this material was intended for the production of silicon which was used for two additional spheres in the context of the redetermination of the Avogadro constant NA, required for the revision of the International System of Units (SI) via fundamental constants which came into force from May 2019. The CCQM pilot study was organized by Physikalisch-Technische Bundesanstalt (PTB). Aqueous silicon solutions were shipped to all participating institutions. The data analysis as well as the uncertainty modelling and calculation of the results was predefined. The participants were provided with an uncertainty budget as a GUM Workbench® file as well as a free software license for the duration of the comparison. The agreement of the values of the molar mass (M(Si) = 27.976 942 577 g mol−1) was excellent with ten out of 11 results reported within the range of relative uncertainty of 1 × 10−8 required for the revision of the SI. KW - Absolute isotope ratio KW - Molar mass KW - Avogadro constant KW - Revision of the SI PY - 2020 DO - https://doi.org/10.1088/1681-7575/abbdbf VL - 57 IS - 6 SP - 065028 PB - IOP Science CY - Cambridge AN - OPUS4-51500 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wegner, Karl David A1 - Resch-Genger, Ute T1 - The 2023 Nobel Prize in Chemistry: Quantum dots N2 - The 2023 Nobel Prize in Chemistry was awarded to Aleksey I. Ekimov (prize share 1/3), Louis E. Brus (prize share 1/3), and Moungi G. Bawendi (prize share 1/3) for groundbreaking inventions in the field of nanotechnology, i.e., for the discovery and synthesis of semiconductor nanocrystals, also termed quantum dots, that exhibit size-dependent physicochemical properties enabled by quantum size effects. This feature article summarizes the main milestones of the discoveries and developments of quantum dots that paved the road to their versatile applications in solid-state lighting, display technology, energy conversion, medical diagnostics, bioimaging, and image-guided surgery. KW - Quantum dots KW - Semiconductor nanocrystals KW - Luminescence KW - Quantitative spectroscopy KW - Quantum yield KW - Advanced nanomaterials KW - Quality assurance KW - Energy transfer PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597843 DO - https://doi.org/10.1007/s00216-024-05225-9 VL - 2024 SP - 1 EP - 11 PB - Springer CY - Cham AN - OPUS4-59784 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kage, Daniel A1 - Hoffmann, Katrin A1 - Nifontova, G. A1 - Krivenkov, V. A1 - Sukhanova, A. A1 - Nabiev, I. A1 - Resch-Genger, Ute T1 - Tempo-spectral multiplexing in flow cytometry with lifetime detection using QD-encoded polymer beads N2 - Semiconductor quantum dots (QDs) embedded into polymer microbeads are known to be very attractive emitters for spectral multiplexing and colour encoding. Their luminescence lifetimes or decay kinetics have been, however, rarely exploited as encoding parameter, although they cover time ranges which are not easily accessible with other luminophores. We demonstrate here the potential of QDs made from II/VI semiconductors with luminescence lifetimes of several 10 ns to expand the lifetime range of organic encoding luminophores in multiplexing applications using time-resolved flow cytometry (LT-FCM). For this purpose, two different types of QD-loaded beads were prepared and characterized by photoluminescence measurements on the ensemble level and by single-particle confocal laser scanning microscopy. Subsequently, these lifetime-encoded microbeads were combined with dye-encoded microparticles in systematic studies to demonstrate the potential of these QDs to increase the number of lifetime codes for lifetime multiplexing and combined multiplexing in the time and colour domain (tempo-spectral multiplexing). These studies were done with a recently developed novel luminescence lifetime flow cytometer (LT-FCM setup) operating in the time-domain, that presents an alternative to reports on phase-sensitive lifetime detection in flow cytometry. KW - Fluorescence life time KW - Flow cytometry KW - Lifetime-encoded beads KW - Quantum dots KW - Multiplexing PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-503316 DO - https://doi.org/10.1038/s41598-019-56938-2 VL - 10 IS - 1 SP - Article number: 653 PB - nature.com AN - OPUS4-50331 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Iwert, C. A1 - Stein, J. A1 - Appelt, C. A1 - Vogt, K. A1 - Rainer, R. J. A1 - Tummler, K. A1 - Mühle, K. A1 - Stanko, K. A1 - Schumann, J. A1 - Uebe, D. A1 - Jürchott, K. A1 - Lisec, Jan A1 - Janek, K. A1 - Gille, C. A1 - Textoris-Taube, K. A1 - Sai, S. A1 - Petersen, A. A1 - Kühl, A. A. A1 - Klipp, E. A1 - Meisel, C. A1 - Sawitzki, B. T1 - TCAIM controls effector T cell generation by preventing Mitochondria-Endoplasmic Reticulum Contact Site-initiated Cholesterol Biosynthesis N2 - T cells need to adapt their cellular metabolism for effector cell differentiation. This relies on alterations in mitochondrial physiology. Which signals and molecules regulate those alterations remains unclear. We recently reported, that the mitochondrial protein TCAIM inhibits activation-induced changes in mitochondrial morphology and function and thus, CD effector T cell formation. Using conditional TCAIM knock-in (KI) and knockout (KO) mice, w now show that it also applies to CD8+ T cells and more importantly, delineate the molecular processes in mitochondria by which TCAIM controls effector cell differentiation. TCAIM KI resulted in reduced activation-induced HIF1α protein expression. Metabolomics and transcriptional data in combination with mathematical flux modeling revealed an impaired induction of anabolic pathways, especially of the mevalonate pathway and cholesterol biosynthesis in TCAIM KI CD8+ T cells. Addition of cholesterol completely rescued HIF1α protein expression, activation and proliferation of TCAIM KI CD8+ T cells. At the molecular level, TCAIM delayed activation-induced mitochondria-ER contact (MERC) formation by binding to MERC promoting proteins such as RMD3 and VDAC2. In summary, we demonstrate that TCAIM suppresses effector cell differentiation by inhibiting MERC formation, which induce HIF1α-mediated increase in cellular metabolism and cholesterol biosynthesis. KW - Mass Spectroscopy KW - Metabolomics KW - Cancer PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-533543 UR - https://www.biorxiv.org/content/10.1101/2021.04.20.440500v1 DO - https://doi.org/10.1101/2021.04.20.440500 VL - April SP - 1 EP - 45 PB - Cold Spring Harbor Laboratory AN - OPUS4-53354 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bandi, V.G. A1 - Luciano, M.P. A1 - Saccomano, M. A1 - Patel, N.L. A1 - Bischof, Th. S. A1 - Lingg, J.G.P. A1 - Tsrunchev, P.T. A1 - Nix, M.N. A1 - Ruehle, Bastian A1 - Sanders, C. A1 - Riffle, L. A1 - Robinson, C.M. A1 - Difilippantonio, S. A1 - Kalen, J.D. A1 - Resch-Genger, Ute A1 - Ivanic, J. A1 - Bruns, O.T. A1 - Schnermann, M. T1 - Targeted multicolor in vivo imaging over 1,000 nm enabled by nonamethine cyanines N2 - Recent progress has shown that using wavelengths between 1,000 and 2,000 nm, referred to as the shortwave-infrared or near-infrared (NIR)-II range, can enable high-resolution in vivo imaging at depths not possible with conventional optical wavelengths. However, few bioconjugatable probes of the type that have proven invaluable for multiplexed imaging in the visible and NIR range are available for imaging these wavelengths. Using rational design, we have generated persulfonated indocyanine dyes with absorbance maxima at 872 and 1,072 nm through catechol-ring and aryl-ring fusion, respectively, onto the nonamethine scaffold. Multiplexed two-color and three-color in vivo imaging using monoclonal antibody and dextran conjugates in several tumor models illustrate the benefits of concurrent labeling of the tumor and healthy surrounding tissue and lymphatics. These efforts are enabled by complementary advances in a custom-built NIR/shortwave-infrared imaging setup and software package for multicolor real-time imaging. KW - Photoluminescence KW - Fluorescence KW - Dye KW - Cyanine KW - Antibody KW - Bioconjugate KW - Conjugate KW - Quantum yield KW - Photophysics KW - Lifetime KW - Sensor KW - NIR KW - SWIR KW - Mechanism KW - Imaging KW - Application KW - Contrast agent KW - Bioimaging PY - 2021 DO - https://doi.org/10.1038/s41592-022-01394-6 VL - 19 IS - 3 SP - 353 EP - 358 PB - Nature Research AN - OPUS4-54465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Winckelmann, Alexander T1 - Taking Chances – Cheese, Chocolate and Laser Spectroscopy N2 - Science Café Adlershof is having its next edition in 2024 on February 20th '24! We will have one speaker next week: Alexander Winckelmann is a PhD student at Bundesanstalt für Materialforschung und -Prüfung and will give a talk about his stay abroad in Switzerland - there will be free chocolates! There will be enough time to ask questions or simply chat with the guests and participants. T2 - Science Café Adlershof CY - Berlin, Germany DA - 20.02.2024 KW - Laser-induced XUV Spectroscopy KW - Multivariate Data Analysis KW - Science Communication PY - 2024 AN - OPUS4-60197 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Le Guevel, X. A1 - Wegner, Karl David A1 - Würth, Christian A1 - Baulin, V. A. A1 - Musnier, B. A1 - Josserand, V. A1 - Resch-Genger, Ute A1 - Koll, J-C T1 - Tailoring the SWIR emission of gold nanoclusters by surface ligand rigidification and their application in 3D bioimaging N2 - The influence of solvent polarity and surface ligand rigidification on the SWIR emission profile of gold nanoclusters with an anistropic surface was investigated. A strong enhancement of the SWIR emission band at 1200 nm was observed when measuring in different local environments: in solution, in polymer composites, and in solids. SWIR in vivo imaging of mice assisted by deep learning after intravenous administration of these gold nanoclusters provides high definition pseudo-3D views of vascular blood vessels. KW - Nano KW - Nanomaterial KW - Metal cluster KW - Photoluminescence KW - Quantum yield KW - Photophysics KW - Lifetime KW - Sensor KW - NIR KW - SWIR KW - Ligand KW - Gold KW - Mechanism KW - Charge transfer KW - Enhancement strategy KW - Imaging KW - Application KW - Contrast agent PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543582 DO - https://doi.org/10.1039/D1CC06737K VL - 58 IS - 18 SP - 2967 EP - 2970 PB - RSC AN - OPUS4-54358 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bertorelle, F. A1 - Wegner, Karl David A1 - Berkulic, M. P. A1 - Fakhouri, H. A1 - Comby-Zerbino, C. A1 - Sagar, A. A1 - Bernadó, P. A1 - Resch-Genger, Ute A1 - Bonacic-Koutecký, V. A1 - Le Guével, X. A1 - Antoine, R. T1 - Tailoring the NIR-II Photoluminescence of Single Thiolated Au25 Nanoclusters by Selective Binding to Proteins N2 - Atomically precise gold nanoclusters are a fascinating class of nanomaterials that exhibit molecule-like properties and have outstanding photoluminescence (PL). Their ultrasmall size, molecular chemistry, and biocompatibility make them extremely appealing for selective biomolecule labeling in investigations of biological mechanisms at the cellular and anatomical levels. In this work, we report a simple route to incorporate a preformed Au25 nanocluster into a model bovine serum albumin (BSA) protein. A new approach combining small-angle X-ray scattering and molecular modeling provides a clear localization of a single Au25 within the protein to a cysteine residue on the gold nanocluster surface. Attaching Au25 to BSA strikingly modifies the PL properties with enhancement and a redshift in the second near-infrared (NIR-II) window. This study paves the way to conrol the design of selective sensitive probes in biomolecules through a ligand-based strategy to enable the optical detection of biomolecules in a cellular environment by live imaging. KW - Fluorescence KW - Aggregation KW - Signal enhancement KW - Cluster KW - Nano KW - Metal KW - NIRII KW - SWIR KW - Sensor KW - Quantum yield KW - Lifetime KW - Photophysics KW - Synthesis KW - Protein KW - Imaging KW - Bioimaging KW - Ligand KW - Gold PY - 2022 DO - https://doi.org/10.1002/chem.202200570 SN - 1521-3765 VL - 28 IS - 39 SP - 1 EP - 8 PB - Wiley-VCH CY - Weinheim AN - OPUS4-55077 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chapartegui-Arias, Ander A1 - Raysyan, A. A1 - Belenguer, A. M. A1 - Jaeger, Carsten A1 - Tchipilov, Teodor A1 - Prinz, Carsten A1 - Abad Andrade, Carlos Enrique A1 - Beyer, S. A1 - Schneider, Rudolf A1 - Emmerling, Franziska T1 - Tailored mobility in a zeolite imidazolate framework (ZIF) antibody conjugate N2 - Zeolitic imidazolate framework (ZIF) hybrid fluorescent nanoparticles and ZIF antibody conjugates have been synthesized, characterized, and employed in lateral-flow immunoassay (LFIA). The bright fluorescence of the conjugates and the possibility to tailor their mobility gives a huge potential for diagnostic assays. An enzyme-linked immunosorbent assay (ELISA) with horseradish peroxidase (HRP) as label, proved the integrity, stability, and dispersibility of the antibody conjugates, LC-MS/MS provided evidence that a covalent link was established between these metal-organic frameworks and lysine residues in IgG antibodies. KW - ZIF KW - ELISA PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532096 DO - https://doi.org/10.1002/chem.202100803 SN - 0947-6539 SN - 1521-3765 VL - 27 IS - 36 SP - 9414 EP - 9421 PB - Wiley-VCH CY - Weinheim AN - OPUS4-53209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hachenberger, Y. U. A1 - Rosenkranz, D. A1 - Kriegel, Fabian L. A1 - Krause, B. A1 - Matschaß, René A1 - Reichardt, P. A1 - Tentschert, J. A1 - Laux, P. A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Luch, A. T1 - Tackling Complex Analytical Tasks: An ISO/TS-Based Validation Approach for Hydrodynamic Chromatography Single Particle Inductively Coupled Plasma Mass Spectrometry N2 - Nano-carrier systems such as liposomes have promising biomedical applications. Nevertheless, characterization of these complex samples is a challenging analytical task. In this study a coupled hydrodynamic chromatography-single particle-inductively coupled plasma mass spectrometry (HDC-spICP-MS) approach was validated based on the technical specification (TS) 19590:2017 of the international organization for standardization (ISO). The TS has been adapted to the hyphenated setup. The quality criteria (QC), e.g., linearity of the calibration, transport efficiency, were investigated. Furthermore, a cross calibration of the particle size was performed with values from dynamic light scattering (DLS) and transmission electron microscopy (TEM). Due to an additional Y-piece, an online-calibration routine was implemented. This approach allows the calibration of the ICP-MS during the dead time of the chromatography run, to reduce the required time and enhance the robustness of the results. The optimized method was tested with different gold nanoparticle (Au-NP) mixtures to investigate the characterization properties of HDC separations for samples with increasing complexity. Additionally, the technique was successfully applied to simultaneously determine both the hydrodynamic radius and the Au-NP content in liposomes. With the established hyphenated setup, it was possible to distinguish between different subpopulations with various NP loads and different hydrodynamic diameters inside the liposome carriers. KW - Single particle ICP-MS KW - Nanoparticle characterization KW - Nano-carrier KW - Iposomes KW - Hydrodynamic chromatography (HDC) KW - Validation PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506609 DO - https://doi.org/10.3390/ma13061447 VL - 13 IS - 6 SP - 1 EP - 14 CY - Basel, Switzerland AN - OPUS4-50660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lisec, Jan A1 - Kobelt, D. A1 - Walther, W. A1 - Mokrizkij, M. A1 - Grötzinger, C. A1 - Jaeger, Carsten A1 - Baum, K. A1 - Simon, M. A1 - Wolf, J. A1 - Beindorf, N. A1 - Brenner, W. A1 - Stein, U. T1 - Systematic Identification of MACC1-Driven Metabolic Networks in Colorectal Cancer N2 - MACC1 is a prognostic and predictive metastasis biomarker for more than 20 solid Cancer entities. However, its role in cancer metabolism is not sufficiently explored. Here, we report on how MACC1 impacts the use of glucose, glutamine, lactate, pyruvate and fatty acids and show the comprehensive analysis of MACC1-driven metabolic networks. We analyzed concentrationdependent changes in nutrient use, nutrient depletion, metabolic tracing employing 13C-labeled substrates, and in vivo studies. We found that MACC1 permits numerous effects on cancer metabolism. Most of those effects increased nutrient uptake. Furthermore, MACC1 alters metabolic pathways by affecting metabolite production or turnover from metabolic substrates. MACC1 supports use of glucose, glutamine and pyruvate via their increased depletion or altered distribution within metabolic pathways. In summary, we demonstrate that MACC1 is an important regulator of metabolism in cancer cells. KW - Mass Spectroscopy KW - Metabolomics KW - Cancer PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-533526 DO - https://doi.org/10.3390/cancers13050978 VL - 13 IS - 5 SP - 1 EP - 22 PB - MDPI Journal Cancers AN - OPUS4-53352 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Srivastava, Priyanka A1 - Fürstenwerth, Paul Christian A1 - Witte, J. F. A1 - Resch-Genger, Ute T1 - Synthesis and spectroscopic characterization of a fluorescent phenanthrene-rhodamine dyad for ratiometric measurements of acid pH values N2 - We present the rational design, synthesis and spectroscopic characterization of a novel dual excitation, three color emitting, pH-responsive fluorescent probe consisting of two phenanthrene and one rhodamine B units linked by click chemistry. The rhodamine moiety, excitable at λEx = 315 nm and at λEx = 560 nm in its ring-opened form, provides the pH-responsive fluorophore, while the pH-insensitive phenanthrene, excited at λEx = 315 nm, serves as inert internal reference, The presence of two phenanthrene moieties enables a blue monomer and a blueish green excimer emission at 351 nm and 500 nm, respectively. Opening of the rhodamine B spirolactam ring at an acidic pH below 5.0 (pKa = 2.59 ± 0.04) switches on its emission at 580 nm. Simultaneously, the phenanthrene excimer emission decreases caused by a change in orientation of the phenanthrene units, while the monomer emission is barely affected. This sensor design enables ratiometric measurements in the low acidic pH range utilizing the intensity ratios of the rhodamine B and phenanthrene excimer emission at 580 nm and 500 nm. Alternatively, also the intensity ratios of the rhodamine B and the phenanthrene monomer emission could be exploited or the sum of the phenanthrene monomer and excimer fluorescence. To the best of our knowledge, this is the first report of ratiometric sensing utilizing such a versatile type of tricolor emissive dyad probe bearing phenanthrene moieties and showing phenanthrene monomer and excimer emission. KW - Fluorescence KW - Optical probe KW - Sensor KW - Dye KW - Rhodamine KW - Synthesis KW - Photophysics KW - PH KW - Quantum yield KW - Quality assurance KW - Mechanism KW - Chemodosimeter KW - Phenanthrene KW - Ratiometric KW - Dyad PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530554 DO - https://doi.org/10.1039/d1nj01573g SN - 1144-0546 VL - 45 IS - 31 SP - 13755 EP - 13762 PB - Royal Society of Chemistry AN - OPUS4-53055 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Matiushkina, Anna T1 - Synthesis and physical properties studies of bifunctional nanocomposites N2 - At present, the field of research on nanostructures is actively developing, which is due to their unique physico-chemical properties compared to bulk materials. Many research activities are focused on obtaining nanocomposites, which combine various types of nanostructures with different properties and function. For example, the development of magneto-luminescent nanocomposites makes it possible to use their luminescence for optical imaging, and their magnetic properties for magnetic targeted delivery and as agents of hyperthermia and magnetic resonance imaging. My master studies as part of the project Goszadanie 2019-1080 at ITMO were focused on the investigation of nanocomposites, consisting of semiconductor quantum dots (QDs) as luminescent component and superparamagnetic iron oxide nanoparticles (SPIONs) as magnetic one, in solution and during their incubation with HeLa cells. The spectrally resolved analysis of the QD photoluminescence (PL) kinetics of the free QDs and the QDs incorporated in these nanocomposites undergoing energy transfer processes allowed for (1) understanding the reasons for the quenching of QD luminescence in cells, (2) evaluating the average distance between the QDs and, based on this, concluding the degree of QD aggregation in cells, and (3) drawing conclusions about the QD-quencher composites integrity in cells. Overall, the analysis of the PL kinetics confirmed that QDs and SPIONs remain bound in the obtained nanocomposites during incubation with cells. To ensure the successful advancement of nanomaterials in biomedicine and the transition from their laboratory preparation and studies to their use in different applications and in industry, it is crucial to develop reliable measurement methods and reference materials candidates for the characterization of functional nanomaterials and assessing the quality of the obtained nanostructures. My recently started project at BAM, which is part of the EU metrology project MeTrINo, will be devoted to this topic. There we will focus on the development of methodologies for the synthesis and characterization of iron oxide nanoparticles, already used in biomedicine, and multi-element lanthanide-based nanoparticles with attractive upconversion luminescence, as reference materials with high monodispersity and reproducibility. Also, these nanoparticles will be functionalized with organic dyes for optical imaging and, probably, the study of the energy transfer phenomena. T2 - Bad Honnef Summer School CY - Bad Honnef, Germany DA - 30.07.2023 KW - Quantum dots KW - Iron oxide nanoparticles KW - Upconversion nanoparticles PY - 2023 AN - OPUS4-58075 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Amouroux, B. A1 - Eftekhari, A. A1 - Roux, C. A1 - Micheau, J. A1 - Roblin, P. A1 - Pasturel, M. A1 - Gauffre, F. A1 - Würth, Christian A1 - Resch-Genger, Ute A1 - Sliwa, M. A1 - Bouchet, A. A1 - Coudret, C. T1 - Synthesis and Emission Dynamics of Sub-3 nm Upconversion Nanoparticles N2 - Reducing the size of upconversion nanoparticles (UCNPs) down to a few nm yields luminescent materials containing a very small number of emitters. Considering the bottom limit of one activator per particle ultrasmall UCNPs offer an unprecedented platform to study the contributions of the energy transfers at play in upconversion luminescence. Maintaining detectable emission despite the limited number of emitting ions and the high surface-to-volume ratio requires suitable particle architectures. Na(Gd-Yb)F4:Tm3+ emissive sub-3 nm diameter 𝜷-phase UCNPs are prepared using a gadolinium-rich composition in situ mixing of the precursors and a microwave high-temperature cycling sequence allowing precise control of the particle size and dispersity. These cores are coated with a NaGdF4 inert shell to minimize the deleterious influence of surface quenching (SQ). Time-resolved luminescence measurements combining standard NIR excitation of the Yb3+ sensitizer and direct UV excitation of the Tm3+ activator are performed to quantify cross relaxation and surface quenching processes. The fine tuning of the number of activators per particle via an optimized synthesis pathway along with the use of an appropriate excitation scheme enabled to provide an accurate analysis of the different mechanisms at play in these model nanoparticles and to characterize the structure of the core-shell architecture. KW - Lanthanide KW - Nanoparticle KW - Luminescence KW - Quantitative spectroscopy KW - Quantum yield KW - Energy transfer KW - Quality assurance KW - Synthesis KW - Surface modification KW - Photophysics PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-606877 DO - https://doi.org/10.1002/adom.202303283 SN - 2195-1071 SP - 1 EP - 13 AN - OPUS4-60687 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herter, Sven-Oliver T1 - Synthesis and application of stable isotopically labeled ergot alkaloids N2 - Ergot alkaloids form a toxicologically relevant group of mold toxins (mycotoxins) that are among the most common contaminants of food and animal feed worldwide. Therefore, reliable controls are indispensable for the minimization of both health risks and economic damages. As a consequence of their toxicological significance, EU limit values for 12 priority ergot alkaloids were established for the first time in 2022. These limits range from 500 µg/kg in rye milling products down to 20 µg/kg in processed cereal-based foods for infants and young children. Despite the use of high-performance liquid chromatography-mass spectrometry to quantify low concentrations of ergots in food, the current European standard procedure EN 17425:2021 cannot be fully applied due to the lack of isotopically labeled reference standards. The complex structure of the ergot alkaloids makes a total synthesis extremely challenging, expensive, and time-consuming. Consequently, we focused on a semi-synthetic approach with the aim of specifically demethylating the N6-atom of the lysergic acid moiety, a shared structural feature among all ergot alkaloids. This resulted in the formation of a norergot alkaloid, which was purified using preparative HPLC. The reaction of the norergot alkaloid with an isotopically labeled electrophilic methyl source, such as iodomethane or dimethyl sulfate, yielded the desired isotopically labeled ergot alkaloid. This methodology enabled the successful synthesis of all 12 stable isotopically labeled priority ergot alkaloids for the first time. Herein we present the problem of the current unavailability of these isotopically labeled standards and our approach to solve this urged demand. Moreover, we are able to present initial data on how these standards enhance the European standard procedure, EN 17425:2021. T2 - 11th International Symposium on RECENT ADVANCES IN FOOD ANALYSIS CY - Prague, Czech Republic DA - 05.11.2024 KW - Reference Material KW - HPLC-MS/MS KW - Mycotoxins KW - Ergot Alkaloids KW - Isotopic Labeling PY - 2024 AN - OPUS4-61690 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herter, Sven-Oliver T1 - Synthesis and application of isotopic labelled ergot alkaloids N2 - Ergot alkaloids form a toxicologically relevant group of mould toxins (mycotoxins) that are among the most common contaminants of foodstuff and animal feed worldwide. Reliable controls are essential to minimise health risks and economic damage. Due to their toxicological relevance, EU limit values for 12 priority ergot alkaloids have been introduced for the first time in 2022 and range from 500 μg/kg in rye milling products down to 20 ug/kg Processed cereal-based foods for infants and young children[1]. High-performance liquid chromatography - mass spectrometry is used to quantify low concentrations of ergots in food, however the European standard analytical procedure cannot be applied due to the lack of isotopically labelled reference standards. The complex structure of the ergot alkaloids makes a total synthesis extremely challenging, expensive and time-consuming. Therefore, we are focusing on different semi-preparative methods (electrochemistry, organic synthesis, heterogeneous catalysis) to specifically N-demethylate the C8 carbon atom of the lysergic acid moiety. The norergot alkaloid formed is then isotopically labelled using an electrophilic methyl source, i.e. iodomethane or dimethyl sulphate to obtain the specific isotopic labelled ergot alkaloid. Initial experiments have shown that N-demethylation of the ergot alkaloid ergotamine is possible by both electrochemical and wet-chemical organic synthesis. The next step is to improve the previously determined reaction conditions to enable the synthesis of norergotamine on a mg scale for further reactions. T2 - ISEAC-41 CY - Amsterdam, Netherlands DA - 20.11.2023 KW - Reference Material KW - Isotope KW - Standards KW - Mykotoxine KW - HPLC-MS PY - 2023 AN - OPUS4-59315 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herter, Sven-Oliver T1 - Synthesis and application of isotopic labelled ergot alkaloids N2 - Ergot alkaloids form a toxicologically relevant group of mould toxins (mycotoxins) that are among the most common contaminants of food and animal feed worldwide. Reliable controls are essential to minimise health risks and economic damage. Due to their toxicological relevance, EU limit values for 12 priority ergot alkaloids have been introduced for the first time in 2022 and range from 500 µg/kg in rye milling products down to 20 ug/kg Processed cereal-based foods for infants and young children[1]. High-performance liquid chromatography - mass spectrometry is used to quantify low concentrations of ergots in food, however the European standard analytical procedure cannot be applied due to the lack of isotopically labelled reference standards. The complex structure of the ergot alkaloids makes a total synthesis extremely challenging, expensive and time-consuming. Therefore, we are focusing on different semi-preparative methods (electrochemistry, organic synthesis, heterogeneous catalysis) to specifically N-demethylate the C8 carbon atom of the lysergic acid moiety. The norergot alkaloid formed is then isotopically labelled using an electrophilic methyl source, i.e. iodomethane or dimethyl sulphate to obtain the specific isotopic labelled ergot alkaloid. Initial experiments have shown that N-demethylation of the ergot alkaloid ergotamine is possible by both electrochemical and wet-chemical organic synthesis. The next step is to adapt the previously determined reaction conditions to enable the synthesis of norergotamine on a mg scale. T2 - 41. International Conference on Environmental & Food Monitoring CY - Amsterdam, Netherlands DA - 20.11.2023 KW - Reference materials KW - Metrology KW - Isotope dilution analysis KW - Calibration standards PY - 2023 AN - OPUS4-59234 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wasternack, J. A1 - Schröder, H. V. A1 - Witte, J. F. A1 - Ilisson, M. A1 - Hupatz, H. A1 - Hille, J. F. A1 - Gaedke, M. A1 - Valkonen, A. M. A1 - Sobottka, S. A1 - Krappe, A. A1 - Schubert, M. A1 - Paulus, B. A1 - Rissanen, K. A1 - Sarkar, B. A1 - Eigler, S. A1 - Resch-Genger, Ute A1 - Schalley, C. A. T1 - Switchable protection and exposure of a sensitive squaraine dye within a redox active rotaxane N2 - In nature,molecular environments in proteins can sterically protect and stabilize reactive species such as organic radicals through non-covalent interactions.Here, wereport a near-infrared fluorescent rotaxane in which the stabilization of a chemically labile squaraine fluorophore by the coordination of a tetralactam macrocycle can be controlled chemically and electrochemically. The rotaxane can be switched between two co-conformations inwhich thewheel either stabilizes or exposes the fluorophore. Coordination by the wheel affects the squaraine’s stability across four redox states and renders the radical anion significantly more stable—by a factor of 6.7—than without protection by a mechanically bonded wheel. Furthermore, the fluorescence properties can be tuned by the redox reactions in a stepwise manner. Mechanically interlockedmolecules provide an excellent scaffold to stabilize and selectively expose reactive species in a co-conformational switching process controlled by external stimuli. KW - Fluorescence KW - Dye KW - Sensor KW - Quantum yield KW - Spectroscopy KW - Photophysics KW - Synthesis KW - Squaraine KW - Switch KW - Redox-active KW - Rotaxane PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-614959 DO - https://doi.org/10.1038/s42004-024-01312-1 VL - 7 SP - 1 EP - 11 AN - OPUS4-61495 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wegner, Karl David T1 - SWIR luminescent nanomaterials – key chemical parameters for bright probes for in vivo bioimaging N2 - A current challenge for studying physio-pathological phenomena and diseaserelated processes in living organisms with non-invasive optical bioimaging is the development of bright optical reporters that enable deep tissue penetration, a high detection sensitivity, and a high spatial and temporal resolution. The focus of this project are nanomaterials, which absorb and emit in the shortwave infrared (SWIR) between ~900–2500 nm where scattering, absorption, and autofluorescence of the tissue are strongly reduced compared to the visible and NIR. T2 - QD2024 - 12th International Conference on Quantum Dots CY - Munich, Germany DA - 18.03.2024 KW - Quantum dots KW - Advanced nanomaterials KW - Fluorescence KW - Quality assurance KW - Gold nanocluster KW - Shortwave infrared KW - Spectroscopy KW - Bioimaging PY - 2024 AN - OPUS4-59783 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Veico, V. P. A1 - Karlagina, Yu. Yu. A1 - Samokhvalov, A. A. A1 - Polyakov, D. S. A1 - Manokhin, S. S. A1 - Radaev, M. M. A1 - Odintsova, G. V. A1 - Gornushkin, Igor B. T1 - Surface Structuring and Reverse Deposition of Nanoporous Titanium Oxides by Laser Ablation of Titanium in Air N2 - The deposition of titanium oxides during titanium laser ablation in air has been experimentally and numerically investigated. A titanium sample was irradiated by nanosecond pulses from an Yb-fber laser with a beam scanned across the sample surface for its texturing. As a result, the hierarchical structure was observed consisting of a microrelief formed by the laser ablation and a nanoporous coating formed by the reverse deposition from the laser induced plasma plume. The chemical and phase composition of the nanoporous coating, as well as the morphology and structure of the surface, were studied using scanning electron microscopy, atomic force microscopy, and X-ray microanalysis. It was found that the deposit consists mostly of porous TiO2 with 26% porosity and inclusions of TiO, Ti2O3, and Ti2O3N. Optical emission spectroscopy was used to control the plasma composition and estimate the effective temperature of plasma plume. The chemical-hydrodynamic model of laser induced plasma was developed to get a deeper insight into the deposition process. The model predicts that condensed titanium oxides, formed in peripheral plasma zones, gradually accumulate on the surface during the plasma plume evolution. A satisfactory agreement between the experimental and calculated chemical composition of the plasma plume as well as between the experimental and calculated composition and thickness of the deposited film was demonstrated. This allows a cautious conclusion that the formation of condensed oxides in the plasma and their consequent deposition onto the ablation surface are among the key mechanisms of formation of porous surface films. KW - Laser ablation KW - Laser induced plasma deposition KW - Surface coating KW - Titanium dioxide KW - Hydrodynamic model KW - Plasma chemistry KW - Emission spectroscopy PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548555 DO - https://doi.org/10.1007/s11090-022-10256-0 VL - 42 IS - 4 SP - 923 EP - 937 PB - Springer AN - OPUS4-54855 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, Zhiyang A1 - Kneipp, Janina T1 - Surface Molecular Patterning by Plasmon-Catalyzed Reactions N2 - Self-assembled monolayers (SAMs) on plasmonic substrates play a significant role applications of surface-enhanced Raman scattering (SERS). At the same time, localized surface plasmon resonances (LSPRs) can be employed for a broad range of plasmon-supported chemical modifications. Here, micropatterning using the derivatization of SAMs on gold nanosubstrates for rewritable SERS-based security labels or as the basis for sensing arrays functionalized with biomolecules is demonstrated using different plasmon-catalyzed reactions. The formation of 4,4′-dimercaptoazobenzene (DMAB) from p-aminothiophenol (PATP) as well as from p-nitrothiophenol (PNTP) and the reduction of PNTP to PATP are used to change the functionality of the substrate in specified positions. Employing LSPR, the reactions are started by illumination using visible laser light at a high intensity in a focal spot of a microscope objective and yield microscopic patterns of the reaction product. The obtained molecular patterns can be erased by other reactions, enabling different strategies for rewriting, encryption, or stepwise functionalization. KW - 4,4′-dimercaptoazobenzene KW - Surface molecular patterning KW - Plasmon-catalyzed reactions KW - p-aminothiophenol KW - p-nitrothiophenol PY - 2021 DO - https://doi.org/10.1021/acsami.1c12410 SN - 1944-8252 VL - 13 IS - 36 SP - 43708 EP - 43714 PB - ACS Publications AN - OPUS4-53341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Döring, Sarah T1 - Surface Immobilization of Thermostable Trypsin for Optimized Antibody Digestion N2 - Therapeutic monoclonal antibodies are the fastest-growing class of biological agents generating yearly sales of approx. USD 220 billion in 2023 which is expected to triple over the next decade. With the growing market significance of therapeutic antibodies, analytical methods allowing reproducible and metrologically traceable quantification need to be developed. In recent years, antibody quantification at the peptide level using liquid chromatography coupled with tandem mass spectrometry (LC-MS) has emerged as the leading technology. The serin protease trypsin has become the gold standard enzyme for digesting intact protein into peptides for this approach. However, many protocols exist that often lead to different results depending on the digestion procedure. In particular, the type and amount of detergents added during sample preparation for protein unfolding before digestion is known to create undesirable structure modifications of proteins (e.g. carbamylation) and significant bias in measurement results by inhibiting enzyme activity. The enzymes themselves can also have an influence, whereby immobilized variants are increasingly being used to improve their stability, minimize self-digestion and enable a higher substrate-enzyme ratio. Here, we studied the implementation of a thermostable and surface-functionalized trypsin-variant for improved antibody digestion. T2 - 23rd Human Proteome Organization World Congress CY - Dresden, Germany DA - 20.10.2024 KW - Antibody Quantification KW - Corundum KW - Enzyme Immobilization KW - LC-MS/MS PY - 2024 AN - OPUS4-61679 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Döring, Sarah T1 - Surface Immobilization of Recombinant Trypsin onto Corundum Particles for Optimized Antibody Digestion N2 - Therapeutic monoclonal antibodies are the fastest-growing class of biological agents and the development of reliable analytical methods for their quantification is becoming increasingly important. Liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) represents one of the leading technologies for antibody quantification. The serin protease trypsin has emerged as the gold standard enzyme for digesting intact protein into peptides for this approach. However, many protocols exist that often lead to different results depending on the digestion procedure. In particular, the type and amounts of detergents added during sample preparation for protein unfolding before digestion is known to create undesirable structure modifications of proteins (e.g. carbamylation) and significant bias in measurement results by inhibiting enzyme activity. The source and nature of the enzyme itself can also have an influence, whereby immobilized variants are increasingly being used to improve their stability, minimize self-digestion and enable a higher substrate-enzyme ratio. Here, we explored the potential of a novel thermostable trypsin and surface-functionalised corundum particles for enhanced antibody digestion. For this purpose, the inactive zymogen was recombinantly produced in E. coli, activated with enterokinase digestion and finally affinity purified by benzamidine purification. The enzyme activity was analogous to commercially available MS-grade trypsin product. In addition, produced trypsin showed increased thermal stability under typical digestion conditions compared to reference product. Furthermore, APTES-silanization followed by glutaraldehyde modification of corundum surface with an additional blocking step prevents nonspecific protein adsorption during the protein digestion procedure and the immobilized enzyme still showed substrate activity after covalent binding. Compared to wild-type and a non-immobilized enzyme, the surface-functionalized thermostable variant showed increased activity at elevated temperatures. Thus, this novel type of trypsin particles promises to not only improve antibody digestion at high temperatures, but also to prevent self-digestion and enable the separation of trypsin from target peptides in LC–MS analysis. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - Antibody Quantification KW - Corundum KW - Enzyme Immobilization KW - LC-MS/MS PY - 2025 AN - OPUS4-63480 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -