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 -