TY - CONF A1 - Resch-Genger, Ute T1 - Typical Measurements in Optical Spectroscopy – Absorption Spectroscopy or Photometry N2 - The basics of absorption spectroscopy (termed also photometry) will be presented with focus on transparent solutions of different molecular and nanocrystalline absorbers and the ultraviolet (UV), visible (vis), and near-infrared (NIR) spectral region. Thereby, also typical sources of uncertainty will be addressed. Subsequently, several examples for typical applications of absorption measurements in the life and material sciences will be briefly shown ranging from aggregation studies and dye labeling densities of biomolecules (dye-to-biomolecule ratios) over optical assays for thiol and protein quantification to the optical determination of the size of semiconductor nanocrystals using size curves. T2 - pHD Seminar CY - Online meeting DA - 03.11.2020 KW - Quantification KW - Absorption KW - Dye KW - Nano particle KW - Method KW - Measurement uncertainty KW - Linearity PY - 2020 AN - OPUS4-51621 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Frenzel, Florian A1 - Würth, Christian A1 - Dukhno, O. A1 - Przybilla, F. A1 - Wiesholler, L. M. A1 - Muhr, V. A1 - Horsch, T. A1 - Mély, Y. A1 - Resch-Genger, Ute T1 - Multiband emission from single β-NaYF4(Yb,Er) nanoparticles at high excitation power densities and comparison to ensemble studies N2 - Ensemble and single particle studies of the excitation power density (P)-dependent upconversion luminescence (UCL) of core and core–shell β-NaYF4:Yb,Er upconversion nanoparticles (UCNPs) doped with 20% Yb3+ and 1% or 3% Er3+ performed over a P regime of 6 orders of magnitude reveal an increasing contribution of the emission from high energy Er3+ levels at P > 1 kW/cm2. This changes the overall emission color from initially green over yellow to white. While initially the green and with increasing P the red emission dominate in ensemble measurements at P < 1 kW/cm2, the increasing population of higher Er3+ energy levels by multiphotonic processes at higher P in single particle studies results in a multitude of emission bands in the ultraviolet/visible/near infrared (UV/vis/NIR) accompanied by a decreased contribution of the red luminescence. Based upon a thorough analysis of the P-dependence of UCL, the emission bands activated at high P were grouped and assigned to 2–3, 3–4, and 4 photonic processes involving energy transfer (ET), excited-state absorption (ESA), cross-relaxation (CR), back energy transfer (BET), and non-radiative relaxation processes (nRP). This underlines the P-tunability of UCNP brightness and color and highlights the potential of P-dependent measurements for mechanistic studies required to manifest the population pathways of the different Er3+ levels. KW - Nano KW - Nanomaterial KW - Upconversion nanoparticle KW - Lanthanide KW - Photoluminescence KW - Quantum yield KW - Photophysics KW - Llifetime KW - Sensor KW - Excitation power density KW - Single particle KW - Brightness KW - NIR KW - Mechanism KW - Color tuning PY - 2021 DO - https://doi.org/10.1007/s12274-021-3350-y SN - 1998-0124 VL - 14 IS - 11 SP - 4107 EP - 4115 PB - Nano Research AN - OPUS4-52364 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Introduction to Fluorescence Spectroscopy N2 - A brief introduction to fluorescence spectroscopy will be provided, ranging from typically measured fluorescence quantities over instrument-specific contributions to measured fluorescence signals to selected applications. In this context, an overview of the photoluminescence properties of molecular and nanoscale luminescence reporters will be given including a brief insight into their photophysics and fluorescence standards designed by division Biophotonics for the calibration and instrument performance validation of fluorescence measuring devices will be presented. T2 - Analytical Academy BAM CY - Online meeting DA - 17.11.2020 KW - Fluorescence KW - Quality assurance KW - Quantification KW - Linearity KW - Measurement uncertainty KW - Method KW - Nano particle KW - Dye PY - 2020 AN - OPUS4-51619 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Design and Quantitative Characterization of Functional Molecular Chromophores and Nanomaterials with UV/vis/NIR/IR Emission and Traceable Optical Measurements N2 - Research of division Biophotonics at the Federal Institute for Materials Research and Testing (BAM) covers several topics including photophysics of molecular and nanocrystalline emitters, the development of signal enhancement, multiplexing, and barcoding strategies, surface group quantification, the rational design of different types of stimuli-responsive optical probes, and concepts and reference materials for the validation of optical-spectroscopic measurements. In the following representative examples for each of these topics are given. Also, current developments like single particle spectroscopy and flow cytometry with lifetime detection and newly certified fluorescence quantum yield standards are presented. T2 - Kolloquium BfR CY - Berlin, Germany DA - 12.10.2020 KW - Fluorescence KW - Quantitative spectroscopy KW - Single particle spectroscopy KW - Multiplexing KW - Reference materials KW - Optical probes KW - Sensor molecules KW - Assay KW - Dye KW - Quantum yield KW - Method development KW - surface group analysis KW - synthesis KW - fluorescence standards PY - 2020 AN - OPUS4-51449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scholtz, Lena T1 - Luminescent, Semiconductor Nanoparticle-loaded Polymer Microbeads - Comparing Particle Architectures N2 - The synthesis of luminescent polymer microparticles stained with different, including non-spherical, semiconductor nanoparticles (NPs) was developed and optimized while ensuring a good preservation of the particle photoluminescence. The aplicability of the different semiconductor NPs was determined to depend on their surface chemistry and shape. Thus, a first correlation of semiconductor NP architecture and applicability could be deduced, which has not been reported before. T2 - 821. WE-Heraeus-Seminar CY - Bad Honnef, Germany DA - 12.11.2024 KW - Nanoparticle KW - Surface chemistry KW - Synthesis KW - Fluorescence KW - Luminescence PY - 2024 AN - OPUS4-61732 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krenzer, Julius A1 - Mueller, Thomas T1 - Aroyl-S,N-ketene acetal based bichromophores exhibiting energy transfer and aggregation induced (dual) emission N2 - A series of aroyl-S,N-ketene acetal based bichromophores is readily synthesized by Buchwald-Hartwig amination and Ullmann reaction in moderate to good yields. The aminated aroyl-S,N-ketene acetals are emissive in the solid state and in the aggregate, but not in solution, thus, they are AIEgens (aggregation induced emission chromogens). Aggregation is induced by fractional alternation of the solvent mixture, here by increasing the water fraction of ethanol/water mixtures. For most derivatives, the emission upon induced aggregation stems solely from the aroyl-S,N-ketene acetal chromophore, regardless whether excitation occurs at the absorption maximum of the triarylamine or the aroyl-S,N-ketene acetal. Therefore, a pronounced energy transfer from the triarylamine donor to the aroyl-S,N-ketene acetal acceptor can be inferred. The color of the emission can be controlled by choosing the para-aroyl substituent. A partial energy transfer could also be observed for some bichromophores, leading to aggregation-induced dual emission (AIDE). In addition, four examples of aminated diaroyl-S,N-ketene acetals were added to the compound library. The electron-withdrawing properties of the additional aroyl group provide a bathochromic shift of the emission band of the aroyl-S,N-ketene acetal. These bichromophores also show AIDE and in one case even aggregation-induced white light emission as a result of additive color mixing. T2 - Beilstein Symposium on pi-Conjugated Molecules and Materials CY - Limburg, Germany DA - 07.11.2023 KW - aggregation-induced dual emission (AIDE) PY - 2023 AN - OPUS4-59006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tavernaro, Isabella T1 - A Multimodal Approach to Quantify Surface Functional Groups on Nanomaterials for Safe and Sustainable by Design N2 - Engineered nanomaterials (NM) with their large surface-to-volume ratios and their for some materials observed size-dependent functional properties are of increasing relevance for current and future developments in various fields such as medical and pharmaceutical industry, computing and electronics or food and consumer products. The performance and safety of NM are determined by the sum of their intrinsic physicochemical properties. Especially, the particle surface chemistry, which is largely controlled by the chemical nature and density of functional groups (FG) and ligands, is an important key driver for NM performance, stability, and processibility as well as the interaction of NM with the environment. Thus, methods for FG quantification can foster the sustainable development of functional and safe(r) NM. Aiming at the development of simple, versatile, and multimodal tools for the quantification of many bioanalytically relevant FG and ligands, we investigated and compared various analytical methods commonly used for FG quantification. This includes electrochemical titration methods, dye-based optical assays, and other instrumental analytical techniques such as nuclear magnetic resonance and thermal analysis methods. The potential of our multimodal approach for FG quantification was demonstrated for commercial and custom-made polymeric and silica particles of varying FG, used as optical pH sensors. In the future, our strategy can contribute to establish multi-method characterization strategies to provide a more detailed picture of the structure-properties relationship. T2 - NanoSAFE & NanoSafety Cluster 2023 CY - Grenoble, France DA - 05.06.2023 KW - Engineered Nanomaterials KW - Safe-by-Design KW - Sustainable-by-Design KW - Surface Group Analysis KW - Silica and Polystyrene Particles KW - Surface Modification KW - Dye KW - Optical Spectroscopy KW - Quantitative NMR KW - Electrochemical Titration KW - Functionalized Nanomaterials KW - Nanosafety PY - 2023 AN - OPUS4-59126 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Osipova, Viktoriia T1 - Incorporation of near-infrared light emitting chromium (III) complexes into silica nanoparticles and spectroscopic characterization N2 - In recent years, chromium (III) complexes have received a lot of attention as novel near-infrared (NIR) emitters triggered by the report on the first molecular ruby Cr(ddpd)2(BF4)3 with a high photoluminescence quantum yield of 13.7% of its near infrared (NIR) emission band and a long luminescence lifetime of 1.122 ms at room temperature.[1] However, in an oxygen-containing environment, the photoluminescence quantum yields and luminescence lifetimes of these chromium(III) complexes show only very small values. This hampers their application as NIR luminescence labels. This application, that cannot be tackled by conventional deoxygenating approaches, requires suitable strategies to protect the luminescence of the chromium(III) complexes from oxygen quenching. An elegant approach to reduce the undesired luminescence quenching by triplet oxygen explored by us presents the incorporation of these chromium(III) complexes into different types of amorphous, non-porous silica nanoparticles, that can be simply surface functionalized, e.g., with targeting ligands and/or other sensor molecules. In this work, as first proof-of-concept experiments, a set of chromium (III) complexes constituting of different ligands and counter anions, were embedded into the core of silica nanoparticles. Subsequently, the optical properties of the resulting luminescent silica nanoparticles were spectroscopically assessed by steady state and time-resolved luminescence spectroscopy. First results of time-resolved luminescence measurements confirm our design concept of nanoscale NIR emissive Cr(III) complex-based reporters T2 - Projekttreffen Nile-Chrome 2.0 CY - Mainz, Germany DA - 11.12.2023 KW - Cr(III) complex KW - NIR KW - Luminescence KW - Nano KW - Silica KW - Lifetime KW - Quantum Yields KW - Particle Synthesis KW - Sensors KW - Probe KW - Surface Group Analysis PY - 2023 AN - OPUS4-59149 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meng, M. A1 - Zhang, R. A1 - Fa, X. A1 - Yang, J. A1 - Cheng, Z. A1 - Qiao, X. A1 - Ou, J. A1 - Würth, Christian A1 - Resch-Genger, Ute T1 - Core−Shell NaYF4:Yb3+/Tm3+@NaGdF4:Ce3+/Eu3+ Nanoparticles for Upconversion and Downconversion Dual-Mode Fluorescence-Based Temperature Sensing N2 - NaYF4 as the core and NaGdF4 as the outer layer were used to obtain NaYF4:Yb3+/Tm3+@NaYF4:Ce3+/Eu3+ nanoparticles. Physical and morphological investigations indicated that the obtained nanoparticles were prepared in a hexagonal shape, with the NaGdF4 shell layer uniformly encapsulated on the NaYF4 core. Strong Tm3+ upconversion emission peaks were observed for a 980-nm-laser-excited sample, while strong Eu3+ downconversion emission peaks were observed for a 254-nm-laser-excited sample. By zonal doping of Tm3+ and Eu3+, their fluorescence intensity can be significantly increased; more importantly, simultaneous temperature measurements with dual-mode upconversion/downconversion can be achieved. The temperature measurement properties of the dual mode were also investigated, and it was discovered that the upconversion 3F3 → 3H6 and 1G4 → 3F4 thermocouple energy levels gave the best temperature measurements with maximum absolute and relative sensitivities of 0.0877 K−1 and 1.95% K−1, respectively, which are better than the current temperature measurement sensitivities of most rare-earth-based materials. This material was prepared as fiber-optic temperature-sensing probes to detect the temperature in the environment in real time and was found to perform excellently for temperature measurement. KW - Upconversion nanoparticle KW - Lanthanide KW - Sensing; temperature KW - Photophysics PY - 2022 DO - https://doi.org/10.1021/acsanm.2c01611 VL - 5 IS - 7 SP - 9266 EP - 9276 PB - American Chemical Society AN - OPUS4-55363 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Würth, Christian A1 - Manley, P. A1 - Voigt, R. A1 - Ahiboz, D. A1 - Becker, C. A1 - Resch-Genger, Ute T1 - Metasurface Enhanced Sensitized Photon Upconversion: Toward Highly Efficient Low Power Upconversion Applications and Nanoscale E-Field Sensors N2 - Large-scale nanoimprinted metasurfaces based on silicon photonic crystal slabs were produced and coated with a NaYF4:Yb3+/Er3+ upconversion nanoparticle (UCNP) layer. UCNPs on these metasurfaces yield a more than 500-fold enhanced upconversion emission compared to UCNPs on planar surfaces. It is also demonstrated how the optical response of the UCNPs can be used to estimate the local field energy in the coating layer. Optical simulations using the finite element method validate the experimental results and the calculated spatial three-dimensional field Energy distribution helps us to understand the emission enhancement mechanism of the UCNPs closely attached to the metasurface. In addition, we analyzed the spectral shifts of the resonances for uncoated and coated metasurfaces and metasurfaces submerged in water to enable a prediction of the optimum layer thicknesses for different excitation wavelengths, paving the way to applications such as electromagnetic field sensors or bioassays. KW - Nanoparticles KW - Upconversion KW - Metasurface KW - Field sensor KW - Emission enhancement KW - Photonic crystal PY - 2020 DO - https://doi.org/10.1021/acs.nanolett.0c02548 VL - 20 IS - 9 SP - 6682 EP - 6689 PB - ACS Publications AN - OPUS4-51427 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geißler, Daniel T1 - Development of reference materials for flow cytometric analysis of extracellular vesicles N2 - The aim of task 1.4 within the EMPIR project 18HLT01 MetVesII is to produce low-RI solid particles with an effective RI between 1.37 and 1.42. To prepare these low-RI solid particles, polymer cores will be coated with a silica shell. Although the bulk RI of polymers, such as polystyrene (RI = 1.59) and PMMA (RI = 1.49), and fused silica (RI = 1.46) are higher than desired, an effective RI below 1.42 will be achieved by using a mesoporous silica shell with tuneable shell-thickness and a polymer core with sufficiently small size. This approach has four advantages: (1) monodisperse commercial polymer particles and silica shell chemistry are available, (2) low-RI solid particles will have a tuneable size and RI, (3) fluorescence can be added by incorporating fluorescent dyes into the polymer cores via an established staining procedure, and (4) fluorescent dyes within the polymer cores are shielded against influences from the sample matrix, e.g. fluorescence quenching effects altering the emission properties of the reference materials. T2 - MetVesII M9 Progress Meeting CY - Budapest, Hungary DA - 12.02.2020 KW - EMPIR 18HLT01 MetVesII KW - Extracellular vesicles (EV) KW - Flow cytometry (FCM) KW - Reference materials KW - Fluorescent particles PY - 2020 AN - OPUS4-50451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Functional Luminophores – From Photophysics to Standardized Luminescence Measurements N2 - Inorganic nanocrystals with linear and nonlinear luminescence in the ultraviolet, visible, near infrared and short-wave infrared like semiconductor quantum dots and spectrally shifting lanthanide-based nanophosphors have meanwhile found applications in the life and material sciences ranging from optical reporters for bioimaging and sensing over security barcodes to solid state lighting and photovoltaics. These nanomaterials commonly have increasingly sophisticated core/shell particle architectures with shells of different chemical composition and thickness to minimize radiationless deactivation at the particle surface that is usually the main energy loss mechanism [1]. For lanthanide-based spectral shifters, particularly for very small nanoparticles, also surface coatings are needed which protect near-surface lanthanide ions from luminescence quenching by high energy vibrators like O-H groups and prevent the disintegration of these nanoparticles under high dilution conditions. [2,3,4]. The identification of optimum particle structures requires quantitative spectroscopic studies focusing on the key performance parameter photoluminescence quantum yield [5,6], ideally flanked by single particle studies to assess spectroscopic inhomogeneities on a particle-to-particle level for typical preparation methods [7,8], Moreover, in the case of upconversion nanoparticles with a multi-photonic and hence, excitation power density (P)-dependent luminescence, quantitative luminescence studies over a broad P range are required to identify particle architectures that are best suited for applications in fluorescence assays up to fluorescence microscopy. Here, we present methods to quantify the photoluminescence of these different types of emitters in the vis/NIR/SWIR and as function of P and demonstrate the importance of such measurements for a profound mechanistic understanding of the nonradiative deactivation pathways in semiconductor and upconversion nanocrystals of different size and particle architecture in different environments. T2 - Eingeladener Vortrag Uni Erlangen CY - Erlangen, Germany DA - 18.01.2023 KW - Semiconductor quantum dot KW - Upconversion nanocrystal KW - Luminescence KW - Quantitative spectroscopy KW - Photophysics KW - Quality assurance KW - Nano KW - Particle KW - Quantum yield KW - Lifetime KW - Standard KW - Reference material KW - Surface analysis KW - Quantification PY - 2023 AN - OPUS4-57011 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tavernaro, Isabella T1 - pH-Responsive Dyad Molecules: MiGraGen Project N2 - Optical pH sensors utilizing colorimetric or fluorescent indicator dyes are highly promising in many biomedical and life science applications where electrochemical sensors fail. For instance, optical sensors are not prone to electrical interferences, they are noninvasive and enable remote measurements. Moreover, fluorescence detection is very fast, highly sensitive, and provides several readout parameters ideal for multiplexing with nanometer resolution using simple, inexpensive, and miniaturizable instrumentation. Here, we present the design of a dyad sensor molecule, consisting of an analyte-responsive and an analyte inert reference fluorophore. T2 - MiGraGen Project Meeting 16.06.2023 CY - Online Meeting DA - 16.06.2023 KW - Dyad molecules KW - pH sensing KW - Fluorescent indicator KW - Ratiometric sensors PY - 2023 AN - OPUS4-58070 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wegner, Karl David T1 - Luminescent Quantum dots – the next-generation nano light bulbs N2 - Fluorescent semiconductor nanocrystals, also known as quantum dots (QDs), enabled many advancements in biotechnology, photovoltaics, photocatalysis, quantum computing and display devices. The high versatility of this nanomaterial is based on their unique size-tunable photoluminescence properties, which can be adjusted from the visible to the near-infrared range. In contrast to other nanomaterials, QDs made the transition from a laboratory curiosity to the utilization in commercial products, like the QLED television screen or in smartphone displays. The best investigated QDs are composed of heavy metals like cadmium or lead, which is not the best choice in terms of toxicity and environmental pollution. A more promising material is Indium Phosphide (InP), which is also currently used by Samsung, Sony and co. in the QLED displays. In this contribution, I would like to give you a sneak peek behind the curtains of nanomaterial synthesis and show how this material is produced, how to stabilize their structural properties, and assess their toxicity in environmentally relevant conditions. Furthermore, I would like to present a synthesis method to accomplish the last open challenge in display technology of a blue luminescent LED based on QDs by introducing a new element to the InP QDs. T2 - The Berlin Postdoc Day CY - Berlin, Germany DA - 03.11.2022 KW - InP KW - Quantum dots KW - Fluorescence KW - Aging KW - Doping KW - Nanomaterial KW - Cytotoxicity PY - 2022 AN - OPUS4-56194 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - A journey in science from a graduate student in physical chemistry to head of division biophotonics N2 - I will provide a personal overview of the most important steps of my career in science, a journey from a graduate student in physical chemistry in an environment dominated by male-scientists over a postdoc with a female professor in the US to the leader of a research group, head of division Biophotonics at BAM. This will include my choices of research topics, how I learnt to write well cited publications, even on topics such as reference materials and quality assurance,1-4 and eventually started to give lectures at Free University Berlin granting me the right to act as first supervisor of undergraduate and graduate students. T2 - Women in Science CY - Erlangen, Germany DA - 22.07.2024 KW - Lanthanide KW - Nanoparticle KW - Silica KW - Quantum dot KW - Polymer KW - Surface group KW - Luminescence KW - Quantitative spectroscopy KW - Quantum yield KW - Lifetime KW - Quality assurance KW - Synthesis KW - Surface modification KW - Photophysics PY - 2024 AN - OPUS4-60724 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wegner, Karl David T1 - Exploring the photoluminescence of gold NCs and Ag2S NPs to boost their SWIR emission N2 - Current challenges and objectives for non-invasive optical bioimaging are deep tissue penetration, high detection sensitivity, high spatial and temporal resolution, and fast data acquisition. A promising spectral window to tackle these challenges is the short-wave infrared (SWIR) ranging from 900 nm to 1700 nm where scattering, absorption, and autofluorescence of biological components are strongly reduced compared to the visible/NIR. At present, the best performing SWIR contrast agents are based on nanomaterials containing toxic heavy-metal ions like cadmium or lead, which raises great concerns for biological applications. Promising heavy-metal free nanoscale candidates are gold nanoclusters (AuNCs) and Ag2S nanoparticles (NPs). The photoluminescence (PL) of both types of nanomaterials is very sensitive to their size, composition of their surface ligand shell, and element composition, which provides an elegant handle to fine-tune their absorption and emission features and boost thereby the size of the signals recorded in bioimaging studies. Aiming for the development of SWIR contrast agents with optimum performance, we dived deeper into the photophysical processes occurring in these nanomaterials, thereby exploring in depth how the environment, surface ligand composition, and the incorporation of transition metals influence the optical properties of AuNCs and Ag2S NPs. We observed a strong enhancement of the SWIR emission of AuNCs upon exposure to different local environments (in solution, polymer, and in the solid state). Addition of metal ions such as Zn2+ to Ag2S based NPs led to a strong PL enhancement, yielding PL quantum yields of about 10% and thus making them highly suitable for non-invasive deep imaging of vascular networks and 3D fluid flow mapping. T2 - NaNaX 10 - Nanoscience with Nanocrystals CY - Klosterneuburg, Austria DA - 03.07.2023 KW - Quantum dots KW - Ag2S KW - Fluorescence KW - SWIR KW - Gold nanocluster KW - Nanomaterial KW - bioimaging PY - 2023 AN - OPUS4-58104 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Functional molecular chromophores and nanomaterials reporters, optical probes, and sensors N2 - •Overview of expertise of division Biophotonics •Functional molecular and nanoscale luminescent reporters, probes, and sensors including design principles available from division Biophotonics •Examples for pH and O2 responsive molecular probes and particle sensors •Surface group quantification Analytical methods and cleavable probes •Concepts & standards for the validation and traceability of optical measurements T2 - FU-Seminar CY - Berlin, Germany DA - 09.12.2022 KW - Particle sensors KW - Surface group quantification KW - Nanoscale luminescent reporters KW - Cleavable probes PY - 2022 AN - OPUS4-56526 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Matiushkina, Anna A1 - Abram, Sarah-Luise A1 - Tavernaro, Isabella A1 - Richstein, R. A1 - Reithofer, M. R. A1 - Andresen, Elina A1 - Michaelis, Matthias A1 - Koch, Matthias A1 - Resch-Genger, Ute T1 - Quantifying Citrate Surface Ligands on Iron Oxide Nanoparticles with TGA, CHN Analysis, NMR, and RP-HPLC with UV Detection N2 - Although citrate is frequently used as a surface ligand for nanomaterials (NMs) such as metal, metal oxide, and lanthanide-based NMs in hydrophilic environments due to its biocompatibility and simple replacement by other more strongly binding ligands in postsynthetic surface modification reactions, its quantification on NM surfaces has rarely been addressed. Here, we present a multimethod approach for citrate quantification on iron oxide nanoparticles (IONPs) broadly applied in the life and material sciences. Methods explored include thermogravimetric (TGA) and elemental (CHN) analysis, providing citrate-nonspecific information on the IONP coating, simple photometry, and citrate-selective reversed-phase high-performance liquid chromatography (RP-HPLC) with absorption (UV) detection and quantitative nuclear magnetic resonance spectroscopy (qNMR). Challenges originating from the strongly absorbing magnetic NM and paramagnetic iron species interfering with optical and NMR Methods were overcome by suitable sample preparation workflows. Our multimethod approach to citrate quantification highlights the advantages of combining specific and unspecific methods for characterizing NM Surface chemistry and method cross-validation. It also demonstrates that chemically nonselective measurements can favor an overestimation of the amount of a specific surface ligand by signal contributions from molecules remaining on the NM surface, e.g., from particle synthesis, such as initially employed ligands and/or surfactants. Our results emphasize the potential of underexplored selective RPHPLC for quantifying ligands on NMs, which does not require a multistep sample preparation workflow such as qNMR for many NMs and provides a higher sensitivity. These findings can pave the road to future applications of versatile HPLC methods in NM characterization. KW - Advanced material KW - Functional group KW - Iron oxide KW - Ligand KW - Nano KW - Particle KW - Quantification KW - Surface analysis PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648632 DO - https://doi.org/10.1021/acs.analchem.5c03024 SN - 0003-2700 VL - 97 IS - 36 SP - 19627 EP - 19634 PB - American Chemical Society (ACS) CY - Washington, DC AN - OPUS4-64863 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Photoluminescence quantum yields of molecular & nanoscale luminophores in the UV/VIS/NIR/SWIR in dispersion and in the solid state N2 - Photophysical and mechanistic studies, the comparison of different emitter classes, and the rational design of the next generation of molecular and nanoscale reporters require quantitative photoluminescence measurements and the reliable determination of the key performance parameter photoluminescence quantum yield (QY), i.e., the number of emitted per absorbed photons. This is of special importance for all photoluminescence applications in the life and material sciences in the UV/vis/NIR/SWIR. T2 - MAF 2024 Conference CY - Valencia, Spain DA - 08.09.2024 KW - Nanoparticle KW - Nano KW - Luminescence KW - Quality assurance KW - Synthesis KW - Standardization KW - Reference material KW - Quantum yield KW - Fluorescence KW - Reference data KW - Integrating sphere spectroscopy KW - ILC KW - Converter material PY - 2024 AN - OPUS4-61072 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pauli, J. A1 - Güttler, Arne A1 - Schneider, T. A1 - Würth, Christian A1 - Resch-Genger, Ute T1 - Fluorescence Quantum Yield Standards for the UV/Visible/NIR: Development, Traceable Characterization, and Certification N2 - The rational design of next generation molecular and nanoscale reporters and the comparison of different emitter classes require the determination of the fluorometric key performance parameter fluorescence quantum yield (Φf), i.e., the number of emitted photons per number of absorbed photons. Main prerequisites for reliable Φf measurements, which are for transparent luminophore solutions commonly done relative to a reference, i.e., a fluorescence quantum yield standard of known Φf, are reliable and validated instrument calibration procedures to consider wavelength-, polarization-, and time-dependent instrument specific signal contributions, and sufficiently well characterized fluorescence quantum yield standards. As the standard’s Φf value directly contributes to the calculation of the sample’s Φf, its accuracy presents one of the main sources of uncertainty of relative Φf measurements. To close this gap, we developed a first set of 12 fluorescence quantum yield standards, which absorb and emit in the wavelength region of 330−1000 nm and absolutely determined their Φf values with two independently calibrated integrating sphere setups. Criteria for standard selection and the configuration of these novel fluorescence reference materials are given, and the certification procedure is presented including homogeneity and stability studies and the calculation of complete uncertainty budgets for the certified Φf values. The ultimate goal is to provide the community of fluorescence users with available reference materials as a basis for an improved comparability and reliability of quantum yield data since the measurement of this spectroscopic key property is an essential part of the characterization of any new emitter. KW - Optical spectroscopy KW - Traceability KW - Reference product KW - Dye KW - Fluorescence KW - Quantum yield KW - Reference material KW - Reference data KW - Certification KW - Quality assurance PY - 2023 DO - https://doi.org/10.1021/acs.analchem.2c05530 VL - 95 SP - 5671 EP - 5677 PB - American Chemical Society AN - OPUS4-58151 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Würth, Christian A1 - Resch-Genger, Ute T1 - Absolute determination of photoluminescence quantum yields of scattering led converter materials how to get it right N2 - Scattering luminescent materials dispersed in liquid and solid matrices and luminescent powders are increasingly relevant for fundamental research and industry. Examples are luminescent nano- and microparticles and phosphors of different compositions in various matrices or incorporated into ceramics with applications in energy conversion, solid-state lighting, medical diagnostics. A key performance parameter is the photoluminescence quantum yield (Φf), i.e., the number of emitted per number of absorbed photons. Φf of transparent luminophore solutions can be obtained relative to a fluorescence Φf standard of known Φf, meanwhile available as certified reference materials.[1] The determination of Φf of scattering liquid and solid samples requires, however, absolute measurements with an integrating sphere setup. Fist we present the results of an interlaboratory comparison of 3 labs from academia and industry on measurements of transparent and scattering dye solutions and YAG:Ce optoceramics, an optical converter material, with commercial stand-alone integrating sphere setups of different illumination and detection geometries.[2] Second we present results for a series of 500 μm-thick polymer films containing different concentrations of photoluminescent and scattering YAG:Ce microparticles.[3] We systematically explored and quantified pitfalls of absolute Φf measurements with special emphasis dedicated to the influence of measurement geometry, optical properties of the blank for determining the number of incident photons absorbed by the sample, and sample-specific surface roughness. Matching Φf values could be easily obtained for transparent dye solutions and scattering dispersions with a blank with scattering properties closely matching those of the sample, Φf measurements of optoceramic samples with different blanks revealed substantial differences of more than 20 %. Our results further reveal that setup configurations can introduce systematic errors resulting in under- or overestimation of the absorbed photon flux and hence an under- or overestimation of Φf. T2 - Shift 2025 CY - La Laguna, Tenerife, Spain DA - 13.10.2025 KW - Quantum Yield KW - LED Converter KW - Luminescent KW - Microparticles PY - 2025 AN - OPUS4-64785 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andresen, Elina T1 - Non-spherical monodisperse multi-element LiYF4:Yb,Tm nanoparticles as potential reference materials for sizing methods – Design, synthesis & characterization N2 - The use of engineered nanoparticles of different size, shape, and composition is continuously increasing in the life and material sciences. This calls for methods and reference materials enabling the reliable and accurate determination of nanoparticle size, particle size distribution, shape, and number concentration. For nano-object with a simple, i.e, spherical shape, the size can be easily determined from measurements of a single parameter, i.e., diameter, by electron microscopy. For non-spherical particles, that much better reflect the properties of most industrially relevant nanomaterials, new correlative approaches for complete 3D characterization are needed and non-spherical reference particles for establishing such methods and the implementation and validation of the respective data fitting routine are compulsory. Therefore, we are currently exploring the potential of differently sized, bipyramidally shaped LiYF4-based NCs doped with different lanthanide ions as reference materials for sizing methods. T2 - E-MRS Spring CY - Strasbourg, France DA - 27.05.2024 KW - Non-sperical NPS KW - Reference materials KW - SAXS PY - 2024 AN - OPUS4-62133 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Goryacheva, O. A. A1 - Wegner, Karl David A1 - Sobolev, A. M. A1 - Häusler, I. A1 - Gaponik, N. A1 - Gorycheva, I. Y. A1 - Resch-Genger, Ute T1 - Influence of particle architecture on the photoluminescence properties of silica‑coated CdSe core/shell quantum dots N2 - Light-emitting nanoparticles like semiconductor nanocrystals (termed quantum dots, QDs) are promising candidates for biosensing and bioimaging applications based on their bright and stable photoluminescent properties. As high-quality QDs are often synthesized in organic solvents, strategies needed to be developed to render them water-dispersible without affecting their optical properties and prevent changes in postmodification steps like the biofunctionalization with antibodies or DNA. Despite a large number of studies on suitable surface modification procedures, the preparation of water-soluble QDs for nanobiotechnology applications still presents a challenge. To highlight the advantages of surface silanization, we systematically explored the influence of the core/multishell architecture of CdSe/CdS/ZnS QDs and the silanization conditions on the optical properties of the resulting silanized QDs. Our results show that the optical properties of silica-coated CdSe/CdS/ZnS QDs are best preserved in the presence of a thick CdS (6 monolayers (ML)) intermediate shell, providing a high photoluminescence quantum yield (PL QY), and a relatively thick ZnS (4.5 ML) external shell, effectively shielding the QDs from the chemical changes during silica coating. In addition to the QD core/shell architecture, other critical parameters of the silica-coating process, that can have an influence on the optical properties of the QD, include the choice of the surfactant and its concentration used for silica coating. The highest PL QY of about 46% was obtained by a microemulsion silica-coating procedure with the surfactant Brij L4, making these water-dispersible QDs to wellsuited optical reporters in future applications like fluorescence immunoassays, biomedicine, and bioimaging. KW - Nano KW - Nanomaterial KW - Particle KW - Semiconductor KW - Quantum do KW - Photoluminescence KW - Photophysics KW - Lifetime KW - Sensor KW - Mechanism KW - Surface KW - Shell KW - Silica KW - Silanization KW - Synthesis PY - 2022 DO - https://doi.org/10.1007/s00216-022-04005-7 SP - 1 EP - 13 PB - Springer AN - OPUS4-54546 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Absolute Determination of Photoluminescence Quantum Yields of Scattering LED Converter Materials – How to Get it Right N2 - Optical measurements of scattering luminescent materials dispersed in liquid and solid matrices and luminescent powders play an important role in fundamental research and industry. Typical examples are luminescent nano- and microparticles and phosphors of different composition in different matrices or incorporated into ceramics with applications in energy conversion, solid-state lighting, medical diagnostics, and security barcoding. The key parameter for the performance of these materials is the photoluminescence quantum yield QY, i.e., the number of emitted photons per number of absorbed photons. QY of transparent luminophore solutions can be determined relatively to a fluorescence quantum yield standard of known QY. Such standards are meanwhile available as certified reference materials.[1] The determination of QY of scattering liquid and solid samples like dispersions of luminescent nanoparticles, solid phosphors, and optoceramics requires, however, absolute measurements with an integrating sphere setup. Although the importance of reliable absolute QY measurements has been recognized, no interlaboratory comparisons (ILCs) on measurement uncertainties and the identification of typical sources of uncertainty have been yet reported. Also, no scattering reference materials with known QY are available. We present here the results of a first ILC of 3 laboratories from academia and industry performed to identify and quantify sources of uncertainty of absolute QY measurements of scattering samples. Thereby, two types of commercial stand-alone integrating sphere setups with different illumination and detection geometries were utilized for measuring QY of transparent and scattering dye solutions and solid phosphors. As representative and industrially relevant solid and scattering samples, YAG:Ce optoceramics of varying surface roughness were chosen, applied, e.g., as converter materials for blue light emitting diodes. Special emphasis was dedicated to the influence of the measurement geometry, the optical properties of the blank, utilized to determine the number of photons of the incident excitation light absorbed by the sample, and the sample-specific surface roughness. While matching QY values could be obtained for transparent dye solutions and scattering dispersions, here using a blank with scattering properties closely matching those of the sample, QY measurements of optoceramic samples with different blanks revealed substantial differences, with the blank's optical properties accounting for measurement uncertainties of more than 20 %. Based upon the ILC results, we recommend non-absorbing blank materials with a high reflectivity (>95 %) such as a 2 mm-thick PTFE target placed on the sample holder which reveals a near-Lambertian light scattering behavior, yielding a homogeneous light distribution within the integrating sphere. T2 - e-MRS 2024 CY - Strasbourg, France DA - 27.05.2024 KW - Luminescence KW - Quantitative spectroscopy KW - Nano KW - Particle KW - Quantum yield KW - Lifetime KW - Quality assurance KW - Phosphor KW - Converter marterial KW - Fluorescence KW - Interlaboratory KW - Comparison KW - Method KW - Uncertainty KW - Reference material PY - 2024 AN - OPUS4-60490 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tavernaro, Isabella T1 - Development of amorphous silica particle based reference materials for surface functional group quantification N2 - Functionalized nanomaterials (NM) with their unique size-dependent properties are of increasing relevance for current and future developments in various fields such as medical and pharmaceutical industry, computing, electronics or food and consumer products. The performance and safety of NM are determined by the sum of their intrinsic physicochemical properties.1 Besides other key parameters, the particle surface chemistry, which is largely controlled by the chemical nature and density of functional groups and ligands, must be considered for a better performance, stability, and processibility of NM, as well as their interaction with the environment. Thus, particle standards with well-designed surfaces and methods for functional group quantification can foster the sustainable development of functional and safe(r) NM.2 Here we provide a brief overview of the ongoing research in division Biophotonics to design tailored amorphous silica reference particles with bioanalytically relevant functional groups and ligands, for the development of standardized and validated surface functional group quantification methods. T2 - Workshop NanoRiskSD project CY - Berlin, Germany DA - 09.06.2022 KW - Nanoparticle KW - Surface analysis KW - Silica KW - Fluorescence KW - Assay PY - 2022 AN - OPUS4-55004 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tavernaro, Isabella T1 - Rational Design of Analyte-responsive Fluorescent Particle Sensors for Life Sciences Applications N2 - Engineered and tailor-made nanomaterials (NM) are of increasing relevance for current and future developments in the life and material sciences for applications, e.g., as drug carriers, fluorescent sensors, and multimodal labels in bioanalytical assays, and reporters for imaging applications. For instance, NM-based reporters and sensors, that are labelled or stained with a multitude of conventional or sensor dyes, have several advantages as compared to molecular probes like enhanced brightness, i.e., amplified signals, ease of designing ratiometric systems by combining analyte-sensitive and inert reference dyes, and increased photostability. Moreover, this can enable the use of hydrophobic dyes in aqueous environments. For rational NM design, choosing and tailoring the intrinsic physicochemical properties, such as particle size, size distribution, morphology, and surface chemistry of the NM application-specific considerations like biocompatibility, ease and low cost of preparation, and colloidal stability and performance in the targeted environment must be considered. In this lecture, different design concepts of inorganic, organic, and hybrid NM and microparticles with hydrophilic surface chemistries and different functionalities are presented that can be used for the targeting of lysosomes; and to monitor functional parameters of endo-lysosomal compartments, like pH or enable oxygen sensing. T2 - Chemical Probes for Lysosomal Biology CY - York, United Kingdom DA - 09.09.2024 KW - Luminescence KW - Quantification KW - Nano KW - Particle KW - Quality assurance KW - Fluorescence KW - Method KW - Uncertainty KW - Reference material KW - Sensor KW - Synthesis KW - Dye KW - pH KW - Silica KW - Polystyrene KW - Surface analysis PY - 2024 AN - OPUS4-62173 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tavernaro, Isabella T1 - Multicolored sensors based on silica and polymeric particles for ratiometric monitoring of pH, oxygen and saccharides N2 - In recent years, the use of functionalized micro- and nanomaterials has increased rapidly for a wide range of applications in the life and material sciences, due to their unique properties in combination with their high surface-to-volume ratio and stability. For instance, functionalized micro- and nanomaterials, that are labeled or stained with a multitude of sensor dyes can be used for monitoring, and quantification of neutral and ionic analytes. These materials have several advantages as compared to conventional molecular probes like enhanced brightness, ease of designing ratiometric systems by combining analyte-sensitive and inert reference dyes, and increased photostability. Moreover, stained nanoparticles can enable the use of hydrophobic dyes in aqueous environments. Versatile templates and carriers for the fabrication of nanosensors by staining and/or labeling with different fluorophores and sensor molecules are biocompatible silica and polymeric particles, because they can be synthesized in large scales at low costs with different surface chemistries. Here we present our work on multicolored sensors for the measurement of pH, oxygen and saccharides utilizing commercially available or in-house synthesized silica and polymeric particles. T2 - 4th European Biosensor Symposium 2023 CY - Aachen, Deutschland DA - 27.08.2023 KW - Nano- and microsensors KW - Silica and polystyrene nanoparticles KW - PH probe KW - Ratiometric sensors KW - Optical spectroscopy KW - Dye KW - Saccharide sensing KW - Multicolored PY - 2023 AN - OPUS4-59125 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - New project on the quantification of functional groups (FGS) on nanomaterials N2 - The surface chemistry of nanomaterials controls their interaction with the environment and biological species and their fate and is hence also relevant for their potential toxicity. This has meanwhile led to an increasing interest in validated and preferably standardized methods for the determination and quantification of surface functionalities on nanomaterials and initiated different standardization projects within ISO/TC 229 and IEC/TC 113 as well as interlaboratory comparisons (ILCs) of different analytical methods for the quantification of surface coatings by OECD. Here we present the results of a first ILC on the quantification of the amount of amino functionalities on differently sized inorganic nanoparticles done by division Biophotonics and the National Research Council of Canada (NRC) and the PWI 19257 on the Characterization and Quantification of Surface Functional Groups and Coatings on Nanoobjects approved by ISO/TC 229 (WG2) in fall 2022 that will result in a VAMAS study on this topic organized by division Biophotonics. Key words: nanoparticles, surface analysis, surface functional groups, quantification, optical assay, qNMR, VAMAS, standardization, ICL, quality assurance, reference material. T2 - Eingeladener Vortrag Universität Erlangen CY - Erlangen, Germany DA - 18.01.2023 KW - Quality assurance KW - Nano KW - Particle KW - Standard KW - Reference material KW - Surface analysis KW - Quantification KW - Interlaboratory comparison KW - Standardization KW - VAMAS PY - 2023 AN - OPUS4-57044 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Matiushkina, Anna T1 - Quantification of Citrate Ligands on the Surface of Nanoparticles N2 - In this study, different methods for determining nanoparticle surface ligands including thermogravimetric analysis (TGA) are explored to quantify citrate as one of the most popular hydrophilic ligands on the surface of nanoparticles such as iron oxide nanoparticles (IONPs). The purpose of work is to understand which analytical methods are best suited for surface chemistry analysis of citrate stabilized IONPs and to validate these methods. T2 - SALSA Make and Measure 2024: Interfaces CY - Berlin, Germany DA - 11.09.2024 KW - Nano KW - Particle KW - Iron oxide KW - Ligand KW - Quantification KW - Advanced material KW - Surface analysis KW - Functional group PY - 2024 AN - OPUS4-62298 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kunc, F. A1 - Nirmalananthan-Budau, Nithiya A1 - Rühle, Bastian A1 - Sung, Y. A1 - Johnston, L.J. A1 - Resch-Genger, Ute T1 - Interlaboratory Comparison on the Quantification of Total and Accessible Amine Groups on Silica Nanoparticles with qNMR and Optical Assays N2 - Risk assessment of nanomaterials requires not only standardized toxicity studies but also validated methods for nanomaterial surface characterization with known uncertainties. In this context, a first bilateral interlaboratory comparison on Surface group quantification of nanomaterials is presented that assesses different reporter-free and labeling methods for the quantification of the total and accessible number of amine functionalities on commercially available silica nanoparticles that are widely used in the life sciences. The overall goal of this comparison is the identification of optimum methods as well as achievable measurement uncertainties and the comparability of the results across laboratories. We also examined the robustness and ease of implementation of the applied analytical methods and discussed method-inherent limitations. In summary, this comparison presents a first step toward the eventually required standardization of methods for surface group quantification. KW - Nano KW - Nanomaterial KW - Surface KW - Method KW - QNMR KW - Quantification KW - Comparison KW - Quality assurance KW - Optical probe KW - Sensor KW - Interlabority comparison KW - Standardization KW - Optical assay KW - Functional group analysis KW - Silica KW - Particle KW - Safety KW - Environment PY - 2021 DO - https://doi.org/10.1021/acs.analchem.1c02162 SN - 1520-6882 VL - 93 IS - 46 SP - 15271 EP - 15278 PB - ASC Publications AN - OPUS4-53818 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Billimoria, K. A1 - Andresen, Elina A1 - Resch-Genger, Ute A1 - Goenaga-Infante, H. T1 - A Strategy for Quantitative Imaging of Lanthanide Tags in A549 Cells Using the Ratio of Internal Standard Elements N2 - One remaining handicap for spatially resolved elemental quantification in biological samples is the lack of a suitable internal standard (IS) that can be reliably measured across both calibration standards and samples. In this work, multielement quantitative intracellular imaging of cells tagged with lanthanide nanoparticles containing key lanthanides, e.g., Eu and Ho, is described using a novel strategy that uses the ratio of IS elements and LA-ICP-TOFMS analysis. To achieve this, an internal standard layer is deposited onto microscope slides containing either gelatin calibration standards or Euand Ho-tagged cell samples. This IS layer contains both gallium (Ga) and indium (In). Monitoring either element as an IS individually showed significant variability in intensity signal between sample or standards prepared across multiple microscope slides, which is indicative of the difficulties in producing a homogeneous film at intracellular resolution. However, normalization of the lanthanide signal to the ratio of the IS elements improved the calibration correlation coefficients from 0.9885 to 0.9971 and 0.9805 to 0.9980 for Eu and Ho, respectively, while providing a consistent signal to monitor the ablation behavior between standards and samples. By analyzing an independent quality control (QC) gelatin sample spiked with Eu and Ho, it was observed that without normalization to the IS ratio the concentrations of Eu and Ho were highly biased by approximately 20% in comparison to the expected values. Similarly, this overestimation was also observed in the lanthanide concentration distribution of the cell samples in comparison with the normalized data. KW - Nanoparticle KW - Nano KW - Luminescence KW - Quality assurance KW - Synthesis KW - Standardization KW - Reference material KW - ICP-MS KW - LA-ICP-MS KW - Quantification KW - Bioimaging PY - 2024 DO - https://doi.org/10.1021/acs.analchem.4c02763 SN - 0003-2700 VL - 96 IS - 30 SP - 12570 EP - 12576 AN - OPUS4-60768 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Scholtz, Lena A1 - Resch-Genger, Ute T1 - Behind the Paper - Dual color pH probes made from silica and polystyrene nanoparticles and their performance in cell studies N2 - In this contribution we highlight the importance of comparison for scientific research while developing a new, functional pH sensor system, and the valuable insights this can provide. KW - Dye KW - Optical Spectroscopy KW - pH probe KW - Silica and Polystyrene Particles KW - Nano KW - Surface groups KW - Safe-by-Design KW - Cell studies KW - Sensors KW - Particle Synthesis KW - Fluorescence PY - 2023 UR - https://communities.springernature.com/posts/dual-color-ph-probes-made-from-silica-and-polystyrene-nanoparticles-and-their-performance-in-cell-studies SP - 1 EP - 2 PB - Springer Nature CY - London AN - OPUS4-59150 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Monks, M.-J. A1 - Würth, Christian A1 - Kemnitz, Erhard A1 - Resch-Genger, Ute T1 - Dopant ion concentration-dependent upconversion luminescence of cubic SrF2:Yb3+, Er3+ nanocrystals prepared by a fluorolytic sol–gel method N2 - A fluorolytic sol–gel method was used for the fast and simple synthesis of small cubic-phase SrF2:Yb3+, Er3+ upconversion (UC) nanocrystals (UCNC) of different composition at room temperature. Systematic studies of the crystal phase and particle size of this Yb3+,Er3+-concentration series as well as excitation power density (P)-dependent UC luminescence (UCL) spectra, UCL quantum yields (ΦUCL), and UCL decay kinetics yielded maximum UCL performance for doping amounts of Yb3+ of 13.5% and Er3+ of 1.3% in the studied doping and P-range (30–400 W cm−2). Furthermore, ΦUCL were determined to be similar to popular β-NaYF4:Yb3+,Er3+. The relative spectral UCL distributions revealed that all UCNC show a strong red emission in the studied doping and P-range (30–400 W cm−2) and suggest that the UCL quenching pathway for unshelled cubic-phase SrF2:Yb3+,Er3+ UCNC differs from the commonly accepted population and depopulation pathways of β-NaYF4:Yb3+,Er3+ UCNC. In SrF2:Yb3+,Er3+ UCNC the 4S3/2 → 4I13/2 transition exhibits a notably stronger sensitivity towards P and reveals increasing values for decreasing Yb3+–Yb3+ distances while the 4I9/2 → 4I15/2 transition is significantly less affected by P and energy migration facilitated UCL quenching. These results emphasize the complexity of the UC processes and the decisive role of the crystal phase and symmetry of the host lattice on the operative UCL quenching mechanism in addition to surface effects. Moreover, the room temperature UCNC synthesis enabled a systematic investigation of the influence of the calcination temperature on the crystal phase of powder-UCNC and the associated UCL properties. Calcination studies of solid UCNC of optimized doping concentration in the temperature range of 175 °C and 800 °C showed the beneficial influence of temperature- induced healing of crystal defects on UCL and the onset of a phase separation connected with the oxygenation of the lanthanide ions at elevated temperature. This further emphasizes the sensitivity of the UC process to the crystal phase and quality of the host matrix. KW - Upconversion nanoparticle KW - Lanthanide KW - Photophysics KW - Synthesis PY - 2022 DO - https://doi.org/10.1039/d2nr02337g SP - 1 EP - 10 PB - Royal Society of Chemistry AN - OPUS4-55364 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Pauli, J. A1 - Güttler, Arne A1 - Richter, Maria A1 - Fiedler, Saskia A1 - Frenzel, Florian A1 - Wegner, Karl David A1 - Würth, Christian T1 - Photoluminescence Quantum Yields of Luminescent Nanocrystals and Particles in the UV/vis/NIR/SWIR N2 - The rational design of functional luminescent materials such as semiconductor quantum dots and lanthanide-based upconversion nanoparticles, all photophysical and mechanistic studies, and the comparison of different emitters require accurate and quantitative photoluminescence measurements. Particularly the reliable determination of the key performance parameter photoluminescence quantum yield (f), the number of emitted per absorbed photons, and the brightness are of special importance for luminescence applications in the life and material sciences and nano(bio)photonics.[1] In this context, examples for absolute measurements of the photoluminescence quantum yields of UV/vis/NIR/SWIR emissive semiconductor quantum dots and rods, made from different materials, and spectrally shifting lanthanide upconversion nanocrystals with different surface chemistries in transparent matrices are presented including excitation wavelength and power density dependent studies utilizing integration sphere spectroscopy.[2,3] In addition, procedures for the absolute determination of the photoluminescence quantum yields of scattering dispersions of larger size quantum rods and differently sized inorganic particles have been developed as well as procedures for the characterization of solid luminescent nanomaterials such as different perovskites and YAG:Cer converter materials.[4] Thereby, challenges and pitfalls of f measurements in different wavelength regions including the SWIR and material-specific effects related to certain emitter classes are addressed, achievable uncertainties are quantified, and relative and absolute measurements of photoluminescence quantum yield measurements are compared to underline limitations of the former approach. Finally, a set of novel UV/vis/NIR quantum yield standards is presented including their certification with a complete uncertainty budget.[5] T2 - NANAX 10 CY - Klosterneuburg, Austria DA - 03.07.2023 KW - Fluorescence KW - Optical spectroscopy KW - Reference data KW - Traceability KW - NIR KW - Scattering KW - Reference material KW - Certification KW - Quality assurance KW - Dye KW - Reference product KW - SWIR KW - Nano KW - Particle KW - Perovskite KW - Integrating sphere spectroscopy KW - Quantum yield PY - 2023 AN - OPUS4-58238 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tavernaro, Isabella T1 - A Multimodal Approach to Quantify Surface Functional Groups and Ligands on Amorphous Silica Nanoparticles N2 - Nowadays amorphous silica nanoparticles (SiO2-NP) are one of the most abundant engineered nanomaterials, that are highly stable and can be easily produced on a large scale at low cost. Surface functionalized SiO2-NP are of great interest in the life and material sciences, as they can be used e.g. as drug carriers, fluorescent sensors, and multimodal labels in bioanalytical assays and imaging applications. Their performance in such applications depends not only on particle size, size distribution, and morphology, but also on surface chemistry, i.e. the total number of surface functional groups (FG) and the number of FG accessible for subsequent functionalization with ligands or biomolecules, which in turn determines surface charge, colloidal stability, biocompatibility, and toxicity. Aiming at the development of simple, versatile, and multimodal tools for the quantification of many bioanalytically relevant FG and ligands, we investigated and compared various analytical methods commonly used for FG quantification. This includes electrochemical titration methods, dye-based optical assays, and other instrumental analytical techniques such as nuclear magnetic resonance and thermal analysis methods. The potential of our multimodal approach for FG quantification was demonstrated for commercial and custom-made silica particles of varying FG, showing not only an influence of the synthesis methods on the number of FG but also on the performance. In the future, our strategy can contribute to establish multi-method characterization strategies to provide a more detailed picture of the structure-properties relationship. T2 - Advanced Materials Safety 2023 CY - Saarbrücken, Germany DA - 08.11.2023 KW - Amorphous silica particles KW - Surface group analysis KW - Ligands KW - Reference material KW - Optical spectroscopy KW - Quantitative NMR KW - Optical assays KW - Titration KW - Engineered nanomaterials KW - Advanced Materials PY - 2023 AN - OPUS4-59124 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geißler, Daniel T1 - Standardisation of concentration measurements of extracellular vesicles for medical diagnoses N2 - Extracellular vesicles (EVs) are cell-derived particles in body fluids, which have excellent potential as next generation biomarkers for the early diagnosis of common diseases, such as cancer and thrombosis. This project aims to tap into the clinical potential of EVs by developing traceable measurements of number concentration, size distribution, refractive index (RI) and fluorescence intensity of cell-specific EVs in human blood and urine. To realise our aims, we will develop synthetic reference materials with physical properties resembling EVs (WP1), instrumentation and procedures to standardise EV measurements in clinical laboratories (WP2), and ready-to-use biological test samples (WP3). These will then be evaluated in an inter-laboratory comparison study across a range (>20) of standard flow cytometers in clinical labs (WP4). T2 - MetVesII M18 Interim Meeting CY - Berlin, Germany DA - 20.10.2020 KW - EMPIR 18HLT01 MetVesII KW - Extracellular vesicles (EV) KW - Flow cytometry (FCM) KW - Reference materials KW - Fluorescent particles KW - Integrating sphere spectroscopy PY - 2020 AN - OPUS4-51653 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tavernaro, Isabella T1 - Quantification of the Total and Accessible Number of Functional Groups and Ligands on Nanomaterials N2 - Surface-functionalized organic and inorganic nanoparticles (NP) are of great interest in the life and material sciences, as they can be used e.g. as drug carriers, fluorescent sensors, and multimodal labels in bioanalytical assays and imaging applications. NP performance in such applications depends not only on particle size, size distribution, and morphology, but also on surface chemistry, i.e. the total number of surface functional groups (FG) and the number of FG accessible for subsequent functionalization with ligands or biomolecules, which in turn determines surface charge, colloidal stability, biocompatibility, and toxicity. Methods for FG quantification should be simple, robust, reliable, fast, and inexpensive, and allow for the characteriza-tion of a broad variety of nanomaterials differing in size, chemical composition, and optical properties. Aiming at the development of simple, versatile, and multimodal tools for the quantification of many bioanalytically relevant FG such as amine, carboxy, thiol and aldehyde functionalities, we investigated and compared various analytical methods commonly used for functional group quantification. This includes electrochemical titration methods, dye-based optical assays, and other instrumental analytical techniques such as nuclear magnetic resonance, mass spectrometry, and thermal analysis methods. T2 - Nanotech France CY - Paris, France DA - 15.06.2022 KW - Optical assays KW - Functionalized nano- and microparticles KW - Particle surface analysis KW - Surface group quantification KW - Terminal functional groups PY - 2022 AN - OPUS4-55208 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Standardization of Flourescence Measurements in the UV/VIS/NIR/IR at BAM N2 - Photoluminescence techniques are amongst the most widely used tools in the life sciences, with new and exciting applications in medical diagnostics and molecular imaging continuously emerging. Advantages include their comparative ease of use, unique sensitivity, non-invasive character, and potential for multiplexing, remote sensing, and miniaturization. General drawbacks are, however, signals, that contain unwanted wavelength- and polarization contributions from instrument-dependent effects, which are also time-dependent due to aging of instrument-components, and difficulties to measure absolute fluorescence intensities. Moreover, scattering systems require special measurement geometries and the interest in new optical reporters with emission > 1000 nm strategies for reliable measurements in the second diagnostic for the comparison of material performance and the rational design of new fluorophores with improved properties. Here, we present strategies to versatile method-adaptable liquid and solid fluorescence standards for different fluorescence parameters. Examples are multi-emitter glasses, spectral fluorescence standards, and quantum yield standards for the UV/vis/NIR. T2 - Konsortiumtreffen Mikroskopie CY - Universität Münster, Germany DA - 20.01.2020 KW - Fluorescence standard KW - Instrument calibration KW - Integrating sphere spectroscopy KW - Fluorescence quantum yield KW - Fluorescent glasses KW - Fluorescence microscopy KW - Particle, imaging PY - 2020 AN - OPUS4-50308 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Harald T1 - Nanoparticle Characterisation - The long way to standardisation N2 - Diese Präsentation gibt einen Überblick über die Entwicklung der Nanopartikelforschung von ca. 2005 bis heute. Beginnend mit den Besonderheiten von Nanopartikeln und der Aufnahme in den menschlichen Körper über Messmethoden bis hin zur Entwicklung einer Prüfrichtlinie im Rahmen der OECD und einem Ausblick über die absehbaren digitalen Entwicklungen. T2 - Abteilungsseminar der Abteilung 4 CY - Berlin, Germany DA - 27.02.2025 KW - Nanomaterials KW - Nano KW - OECD KW - Standardisierung KW - Advanced Materials PY - 2025 AN - OPUS4-64977 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - da Rocha, Morgana A1 - Chaves, Eduardo T1 - Assessment of Pd Nanoparticles as Chemical Modifiers and Preconcentration Agents for Cd Determination in River Water by HR-CS GFAAS N2 - Cadmium is a heavy metal that can be hazardous to environmental and human health, even in trace levels.[1] In this way, the extraction and/or preconcentration of this element from environmental samples, such as river water, is important to obtain information about the composition and monitoring of potential contamination.[2] High-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GFAAS) is widely used for Cd determination. However, the determination of this element at trace-level can be challenging, especially in complex matrices. Thus, nanoparticles (NPs) can be used as an alternative for the extraction and preconcentration of Cd in environmental samples, minimizing the potential interferences and improving the method´s limit of detection (LOD). Considering that Pd is also widely used as a “universal” chemical modifier, this project aims todevelop PdNPs capped with 3-mercaptopropionic acid (MPA) to assess its potential as a chemical modifier and preconcentration agent for Cd determination by HR-CS GF AAS in river water. In this way, the synthesis of PdNPs was performed in an aqueous medium by using ascorbic acid as a reducing agent. The characterization of PdNPs was performed by checking the size via dynamic light scattering (DLS), transmission electron microscopy (TEM), and inductively coupled plasma mass spectrometer in single particle mode (spICP-MS), where the median size was 56 ± 14 nm. The temperature program of HR-CS GFAAS was optimized for river water under three conditions: using Pd(NO3)2/Mg2+ (0.01%/0.5% m/v) as a chemical modifier (condition A), using Pd NPs as a chemical modifier (condition B), and without chemical modifiers (condition C). The pyrolysis and atomization temperatures for condition A were 900 and 1900 ºC, for condition B were 700 ºC and 1900 ºC, and for condition C were 500 and 1900ºC, respectively. Besides the temperature of pyrolysis for the universal chemical modifier being higher than that of PdNPs, using the PdNPs, the absorbance is significantly greater, according to the t-test for pairs, at a 95% confidence level. In addition, the evaluation of the preconcentration property of the PdNP was performed by adding 1 µg L-1 of Cd2+ in buffer pH 4 in two systems: one with and the other without PdNPs. After 1 h of stirring, both systems were centrifuged at 3600 rpm for 10 min, and the absorbance in HR-CS GFAAS for Cd in both supernatants was evaluated. According to ANOVA from the t-test, at a 95% confidence level, there was a significant difference in the absorbance, indicating that Cd is interacting with the PdNPs. A multifactorial planning 2k, where k is the number of parameters of the extraction, which was time of extraction (10; 35; 60 min), Volume of Pd NPs (100; 300; 500 µL), pH (3; 5; 7), was used to evaluate the parameters with significant influence in the preconcentration of Cd2+. According to ANOVA, with 95% confidence, there is no lack of fit, and the parameters volume of PdNP and pH significantly influenced the response. In this way, the Doehlert methodology surface will be applied to both significant parameters. The goal is to achieve optimal conditions that increase the extraction efficiency of Cd2+ from environmental samples. The results indicate that the developed material is promising to use as a chemical modifier and for the preconcentration of Cd2+ in environmental samples. T2 - 17th Rio Symposium on Atomic Spectrometry (RSAS 2025) CY - Sao Pedro, Brazil DA - 12.11.2025 KW - Pd Nanoparticles KW - HR-CS GFAAS KW - Cadmium Ion Sensing KW - Particle Characterization KW - Particle Surface PY - 2025 AN - OPUS4-64997 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Batatia, Ilyes A1 - Benner, Philipp A1 - Chiang, Yuan A1 - Elena, Alin M. A1 - Kovács, Dávid P. A1 - Riebesell, Janosh A1 - Advincula, Xavier R. A1 - Asta, Mark A1 - Avaylon, Matthew A1 - Baldwin, William J. A1 - Berger, Fabian A1 - Bernstein, Noam A1 - Bhowmik, Arghya A1 - Bigi, Filippo A1 - Blau, Samuel M. A1 - Cărare, Vlad A1 - Ceriotti, Michele A1 - Chong, Sanggyu A1 - Darby, James P. A1 - De, Sandip A1 - Della Pia, Flaviano A1 - Deringer, Volker L. A1 - Elijošius, Rokas A1 - El-Machachi, Zakariya A1 - Fako, Edvin A1 - Falcioni, Fabio A1 - Ferrari, Andrea C. A1 - Gardner, John L. A. A1 - Gawkowski, Mikołaj J. A1 - Genreith-Schriever, Annalena A1 - George, Janine A1 - Goodall, Rhys E. A. A1 - Grandel, Jonas A1 - Grey, Clare P. A1 - Grigorev, Petr A1 - Han, Shuang A1 - Handley, Will A1 - Heenen, Hendrik H. A1 - Hermansson, Kersti A1 - Ho, Cheuk Hin A1 - Hofmann, Stephan A1 - Holm, Christian A1 - Jaafar, Jad A1 - Jakob, Konstantin S. A1 - Jung, Hyunwook A1 - Kapil, Venkat A1 - Kaplan, Aaron D. A1 - Karimitari, Nima A1 - Naik, Aakash A. A1 - Csányi, Gábor T1 - A foundation model for atomistic materials chemistry N2 - Atomistic simulations of matter, especially those that leverage first-principles (ab initio) electronic structure theory, provide a microscopic view of the world, underpinning much of our understanding of chemistry and materials science. Over the last decade or so, machine-learned force fields have transformed atomistic modeling by enabling simulations of ab initio quality over unprecedented time and length scales. However, early machine-learning (ML) force fields have largely been limited by (i) the substantial computational and human effort required to develop and validate potentials for each particular system of interest and (ii) a general lack of transferability from one chemical system to the next. Here, we show that it is possible to create a general-purpose atomistic ML model, trained on a public dataset of moderate size, that is capable of running stable molecular dynamics for a wide range of molecules and materials. We demonstrate the power of the MACE-MP-0 model—and its qualitative and at times quantitative accuracy—on a diverse set of problems in the physical sciences, including properties of solids, liquids, gases, chemical reactions, interfaces, and even the dynamics of a small protein. The model can be applied out of the box as a starting or “foundation” model for any atomistic system of interest and, when desired, can be fine-tuned on just a handful of application-specific data points to reach ab initio accuracy. Establishing that a stable force-field model can cover almost all materials changes atomistic modeling in a fundamental way: experienced users obtain reliable results much faster, and beginners face a lower barrier to entry. Foundation models thus represent a step toward democratizing the revolution in atomic-scale modeling that has been brought about by ML force fields. KW - Materials Design KW - Thermal Conducitivity KW - Nanoparticles KW - Batteries PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-647829 DO - https://doi.org/10.1063/5.0297006 SN - 0021-9606 VL - 163 IS - 18 SP - 1 EP - 89 PB - AIP Publishing AN - OPUS4-64782 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 - CONF A1 - Tavernaro, Isabella T1 - Multivalent presentation of phenylpropenic acid amide inspired ligands by various nanoparticles and their potential use in anti-inflammatory therapy N2 - Over the years, inflammation has become one of the most rapidly developing areas in medical research, due to new studies indicating its important role in chronical diseases, thrombosis and cancer. A promising target for anti-inflammatory therapy are the multistep adhesion process of leukocytes from the blood vessels into the inflamed tissue. and the numerous involved receptors and ligands. In particular, selectins and their respective carbohydrate ligands can inhibit this key step of the inflammation cascade. In previous work, it was shown that the multivalent presentation of highly negatively charged sulfated and carboxylated ligands on the particle surface can mimic natural selectin binders and increase the inhibition significantly. Recent studies of the antioxidant and health promoting properties of cocoa, dark chocolate and red clover indicating potential anti-inflammatory properties of their clovamide-type phenylpropenoic acid amides, which are able to inhibit p-selectin expression and platelet-leukocyte interactions. Following the idea of small-molecule targeting drugs, we selected different epitopes and immobilized their sulfated derivatives onto different types nanoparticles, followed by a screening of their performance. T2 - SALSA Make and Measure 2024: Interfaces CY - Berlin, Germany DA - 11.09.2024 KW - Gold colloids KW - Surface group analysis KW - Method KW - Quantification KW - Screening KW - Nano KW - Particle KW - Synthesis KW - Quality assurance KW - Surface ligands PY - 2024 AN - OPUS4-62159 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - 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 - CONF A1 - Tavernaro, Isabella T1 - Quantification of surface functional groups on inorganic and organic nanomaterials using cleavable reporters N2 - Engineered nanomaterials (NM) with their unique size-dependent properties are of increasing relevance for current and future developments in various fields such as medical and pharmaceutical industry, computing and electronics or food and consumer products. The performance and safety of NM are determined by the sum of their intrinsic physicochemical properties. Especially, the particle surface chemistry, which is largely controlled by the chemical nature and density of functional groups and ligands, is an important key driver for the performance, stability, and processibility of NM, as well as their interaction with the environment. Thus, methods for functional group quantification can foster the sustainable development of functional and safe(r) NM. Aiming at the development of simple, versatile and multimodal tools for the quantification of common bioanalytically relevant functional groups, we designed a catch-and-release assay based on cleavable probes that enable the quantification of the cleaved-off reporters in the supernatant after particle separation. Thus, the approach circumvents interferences resulting from particle light scattering and sample-inherent absorption or emission. To study the potential of the assay, commercially available and in-house synthesized aminated and carboxylated polymer and silica nanoparticles of different functional group densities were tested. Our cleavable probe strategy can be easily adapted to other analytical techniques requiring different reporters, or to different types of linkers that can be cleaved thermally, photochemically, or by variation of pH, utilizing well-established chemistry. In addition, it can contribute to the development of multi-method characterization strategies to provide a more detailed picture of the intrinsic physicochemical property - performance/safety relationships and thus can support the design of tailored nanomaterials with better controlled properties. T2 - E-MRS Spring Meeting 2021 / ALTECH 2021 - Analytical techniques for precise characterization of nanomaterials CY - Online meeting DA - 31.05.2021 KW - Surface modified nano- and microparticles KW - Optical assays KW - Particle surface analysis KW - Surface functional group quantification PY - 2021 AN - OPUS4-55596 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Srivastava, Priyanka T1 - Multi-color nanosensors for ratiometric measurements of acidic, neutral, and basic pH based on silica and polystyrene particles N2 - pH presents one of the most important analytes in the life and material sciences, indicating, e.g., diseases and corrosion processes. This includes the optical monitoring of pH in living cells for studying cellular internalization pathways, such as phagocytosis, endocytosis, and receptor mediated internalization with the aid of molecular and nanoscale fluorescent sensors. Nanoparticle (NP)-based sensors, that are labelled or stained with a multitude of sensor dyes, have several advantages as compared to conventional molecular probes like enhanced brightness, i.e., amplified signals, ease of designing ratiometric systems by combining analyte-sensitive and inert reference dyes, and increased photostability. Moreover, this can enable the use of hydrophobic dyes in aqueous environments. Versatile templates and carriers for the fabrication of nanosensors by staining and/or labelling with different fluorophores and sensor molecules are surface-functionalized particles like silica (SiO2) and polystyrene (PS) particles. Here we present a platform of blue-red-green fluorescent pH nanosensors for the measurement of acidic, neutral, and basic pH utilizing both types of matrices and two spectrally distinguishable sensor dyes with an integrated reference dye and demonstrate its applicability for cellular studies. T2 - E-MRS Spring Meeting 2022 CY - Online meeting DA - 30.05.2022 KW - Nanosensors KW - pH sensing KW - Silica- and polystyrene particles KW - Ratiometric sensors KW - Fluorescence PY - 2022 AN - OPUS4-55597 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Harald T1 - The digital product passport N2 - This presentation contains information for industry and the scientific communitiy about the new digital product passport and the demands from the EU. Furthermore a short overview is given about the different supporting activities which are currently under developement by BAM. T2 - 3. Netzwerktag Cluster Nanotechnologie CY - Würzburg, Germany DA - 02.07.2025 KW - DPP KW - ESPR KW - Product Passport KW - Ökodesignrichtlinie KW - DMP PY - 2025 AN - OPUS4-64964 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Liaison Report ISO/TC 229 for ISO/TC 202 and vice-versa N2 - The liaison between the two ISO technical committees TC 229 Nanotechnologies and TC 202 Microbeam analysis, in both directions, is described in detail with highlight on the projects under developement since 2023 and which involve input/knowledge from ISO/TC 202. T2 - 31st Plenary Meeting of ISO/TC202 Microbeam Analysis CY - Tokio, Japan DA - 29.10.2024 KW - ISO TC 202 KW - ISO TC 229 KW - Standardisation KW - Nanotechnologies KW - Microbeam analysis PY - 2024 AN - OPUS4-61511 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sachse, René T1 - Operando electrochemical spectroscopic ellipsometry: Material properties of highly active mesoporous IrO IrOxfilms revealed under realistic OER conditions N2 - Rising energy demand and the impending climate change require the development of a sustainable, fossil-free fuel and chemical production on a global scale. Hydrogen production via water electrolysis will be a fundamental cornerstone in this endeavor. The activity and stability of respective electrode coatings strongly depends on the coating's properties, i.e. phase composition, crystallinity, electrical conductivity, accessible surface, wettability and many other factors. The key to the development of improved catalysts is a better understanding of the relations between their performance, stability and physicochemical properties. However, those relations can be complex, and are strongly influenced also by the reaction environment. Hence, operando analysis of the catalyst material during catalysis at realistic potentials and current densities is highly desirable. Yet, many analytical techniques cannot be applied in liquid environments at realistic potentials and current densities. We propose environmental ellipsometric analysis in a dedicated electrochemical flow cell as a new method to evaluate gas evolution reactions operando under realistic working conditions. Figure 1 illustrates schematically the developed technique. Key factors to success are highly active model-type catalysts with template-controlled porosity, a suitable sample environment, a deep understanding of the spectroscopic method and respective model development, as well as concise cross validation with numerous other analytical techniques. The method was developed and validated by analyzing a calcination series (300 - 600°C) of mesoporous templated IrOx films ex-situ and operando under oxygen evolution reaction (OER) conditions. The employed environmental electrochemical spectroscopic ellipsometric analysis (ECSE) revealed during OER the change of optical and electronic properties, i.e. the dielectric functions (real ε1 and imaginary part ε2), electrical and electronic properties such as resistivity (ρ) and band-to-band transitions (p-d band transitions). Film thickness and porosity were validated by means of scanning electron microscopy (SEM), X-ray reflectometry (XRR) or ellipsometric porosimetry (EP), electrical and electronic properties by means of conductivity measurements, X-ray photoelectron spectroscopy (XPS) or UV-Vis-NIR absorption spectroscopy. The electronic structures of the catalysts from valence electron energy loss spectra (VEELS) derived from the real (ε1) and imaginary part (ε2) of the dielectric function from SE measurements reveal a direct correlation with electrochemical activities in OER. In the presentation reversible and irreversible potential-dependent changes of the catalyst properties during operation will be discussed along with the dynamics of gas formation, transport and dissolution at different potentials. T2 - 54. Jahrestreffen deutscher Katalytiker CY - Online meeting DA - 16.03.2021 KW - Spectroscopic ellipsometry KW - Electrocatalysis KW - Oxygen evolution reaction KW - Mesoporous iridium oxide films KW - Non-destructive operando analysis PY - 2021 AN - OPUS4-52928 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Reliable, and reproducible physico-chemical data of nanomaterials for risk assessment N2 - Nanoforms with at least one dimension below 100 nm have an important part to play in more and more areas of our daily life. Therefore, risk assessment of these materials is becoming increasingly important. In this context, the European Chemical Agency (ECHA) considered eleven physico-chemical properties as relevant, of which the following six are essential for the registration: chemical composition, crystallinity, particle size, particle shape, surface chemistry and specific surface area. Four of these priority properties can be obtained with electron microscopy and surface analytics like XPS and ToF-SIMS. The reliability of this data must be ensured, especially for their use for grouping and read across approaches. On the other hand, the “reproducibility” crisis has revealed major shortcomings in the reliability of published data. In a case study, we show how the quality of the data can be ensured by using existing standards and protocols of each step in the workflow of sample characterization. As exemplary samples, two Al-coated TiO2 samples as nanopowders were selected from the JRC repository, capped either with a hydrophilic or a hydrophobic organic ultrathin shell. SEM results provided the size and shape of the nanoparticles, a first overview about the composition was obtained with EDS. XPS and ToF-SIMS supplied the surface chemistry, especially information about the shell and the coating of the particles. Standards and protocols of all steps of the analytical workflow including preparation and data reduction are discussed regarding reliable and reproducible data. Additionally, uncertainties for the different steps are specified. Only such a detailed description of all these factors allows a comprehensive physico-chemical characterization of the nanoparticles with understanding of their potential risk assessment. T2 - ECASIA 2022 CY - Limerick, Ireland DA - 29.05.2022 KW - Reference data KW - Risk assessment KW - Nanomaterials KW - Titania PY - 2022 AN - OPUS4-54961 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - VAMAS TWA 37 - Quantitative Microstructural Analysis & Liaison with ISO/TC 202 Microbeam Analysis, Liaison with ISO N2 - The progress in activities on Microbeam Analysis under VAMAS/TWA 37 is reviewed. Particularly the liaison with the new projects within the ISO technical committee TC 202 is presented and discussed with respect to the possibility of identifying and launching related VAMAS projects. Need of more promotion for the engagement of more participants from industry and academia at national, European and international level is highlighted. Also, the competition with the other technical working areas (on 'nano' or materials-related) is critically discussed. Further, a short overview of the VAMAS areas of activities is given where Germany is involved. T2 - Versailles Project on Advanced Materials and Standards (VAMAS) 46th Steering Committee Meeting CY - Online meeting DA - 08.09.2021 KW - VAMAS KW - Nanoparticles KW - Standardisation KW - Inter-laboratory comparison KW - ISO/TC 202 KW - ISO/TC 229 KW - ISO/TC 201 KW - Microstructure KW - EBSD PY - 2021 UR - http://www.vamas.org/twa/ AN - OPUS4-53237 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - VAMAS ILC of functionalized Graphene by XPS and Graphene Oxide by SEM N2 - The ideas of the planned VAMAS interlaboratory comparisons of functionalized graphene and graphene oxide are presented. T2 - Stakeholder Advisory Board ISO-G-Scope CY - Online meeting DA - 12.01.2022 KW - Graphene KW - XPS KW - SEM PY - 2022 AN - OPUS4-54375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hodoroaba, Vasile-Dan A1 - Fagan, J. T1 - Contributors invited for two studies on concentration of bimodal silica nanoparticle and bipyramidal titania N2 - International standardisation network VAMAS is calling for participants in two studies on the measurement of (relative) number concentration of bimodal silica nanoparticles including deposition from liquid suspension and the measurement of particle size and shape distribution of bipyramidal titania including deposition from liquid suspension. KW - Nanoparticles KW - VAMAS KW - Inter-laboratory comparison KW - TiO2 KW - SiO2 PY - 2021 UR - https://www.iom3.org/resource/contributors-invited-for-two-studies-on-concentration-of-bimodal-silica-nanoparticle-and-bipyramidal-titania.html SP - 1 EP - 2 PB - Institute of Materials, Minerals and Mining (IOM3) CY - London, UK AN - OPUS4-54410 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hodoroaba, Vasile-Dan T1 - BAM reference data - EDS raw data of Al-coated titania nanoparticles (JRCNM62001a and JRCNM62002a) N2 - EDS spectra of Al-coated titania nanoparticles (JRCNM62001 and JRCNM62002a) provided by the JRC repository are provided. KW - EDS KW - Titania nanoparticles KW - BAM reference data PY - 2021 DO - https://doi.org/10.5281/zenodo.4986420 PB - Zenodo CY - Geneva AN - OPUS4-52833 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bennet, Francesca A1 - Hodoroaba, Vasile-Dan T1 - BAM reference data - SEM raw data for the particles size distribution of Al-coated titania nanoparticles (JRCNM62001a and JRCNM62002a) N2 - SEM raw images of Al-coated titania nanoparticles (JRCNM62001 and JRCNM62002a) provided by the JRC repository are provided together with the particle size distribution of the minimum Feret Diameter extracted from the given images. KW - SEM KW - Titania nanoparticles KW - Particle size distribution KW - BAM reference data PY - 2021 DO - https://doi.org/10.5281/zenodo.5007367 PB - Zenodo CY - Geneva AN - OPUS4-52836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bayerlein, Bernd T1 - Adapting FAIR Practices in Materials Science: Digital Representation of Material-Specific Characterization Methods N2 - Age-hardenable aluminum alloys undergo precise heat treatments to yield nanometer-sized precipitates that increase their strength and durability by hindering the dislocation mobility. Tensile tests provide mechanical properties, while microstructure evaluation relies on transmission electron microscopy (TEM), specifically the use of dark-field TEM images for precise dimensional analysis of the precipitates. However, this manual process is time consuming, skill dependent, and prone to errors and reproducibility issues. Our primary goal is to digitally represent these processes while adhering to FAIR principles. Ontologies play a critical role in facilitating semantic annotation of (meta)data and form the basis for advanced data management. Publishing raw data, digital workflows, and ontologies ensures reproducibility. This work introduces innovative solutions to traditional bottlenecks and offers new perspectives on digitalization challenges in materials science. We support advanced data management by leveraging knowledge graphs and foster collaborative and open data ecosystems that potentially revolutionize materials research and discovery. T2 - TMS - Specialty Congress 2024 CY - Cleveland, Ohio, US DA - 16.06.2024 KW - FAIR KW - Research Data Management KW - Semantic Interoperability KW - Ontologies KW - Materials and Processes Data Reusability PY - 2024 AN - OPUS4-60375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Madbouly, Loay Akmal T1 - Chemical Analysis of Functionalized Graphene along the Production Chain N2 - Graphene has been commercialized for over a decade. It is usually used in the form of suspensions or inks. In this study, we analyze the starting material for commercial functionalized graphene (FG) solutions and inks as well as their starting material (FG powders) using X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), energy-dispersive X-Ray spectroscopy (EDX), time of flight secondary ion mass spectrometry (ToF-SIMS) and Auger electron spectroscopy (AES). Graphene was functionalized with fluorine, oxygen, ammonia, and carboxylic acid. Our results suggest a significant effect of water and commercial resins on the presence as well as the morphological behavior of graphene and associated functionalized group. For example, XPS analysis shows some significant differences between the solutions and the starting materials (powders). These changes can be explained by the location of the functionalization at the outer most surface as indicated by Chemello et al. T2 - MaterialsWeek 2024 CY - Limassol, Cyprus DA - 17.06.2024 KW - Functionalized graphene KW - Commercial graphene KW - Graphene inks PY - 2024 AN - OPUS4-60448 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Morphological and chemical analysis of mesoporous mixed IrOx-TiOy thin films as electrode materials N2 - Porous films play an important role particularly in energy applications like photovoltaics, electrolysis or batteries. Thin film properties such as thickness, chemical composition, crystallinity of the framework, and porosity define the activity of the porous films. The accurate morpho-chemical characterisation of mesoporous thin films is a challenging analytical task which requires the consideration of new analytical approaches based on the combination of data of different methods able to address the structure and chemical composition at the nanoscale. In this contribution we characterise thin mesoporous iridium-titanium mixed oxide film properties by Electron Probe Microanalysis (EPMA) with Energy-Dispersive X-ray Spectroscopy (EDS) at an SEM applied in a dedicated “thin film analysis” approach (1). Thus, the film mass deposition, film thickness and the film density can be determined. Further, by dividing the measured film density to an assumed (theoretical) metal oxide framework (skeletal) density, the thin film porosity can be extracted, too. In order to assess the homogeneity of the thin film properties like the chemical composition, Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) and Auger Electron Spectrometry are applied in the depth profiling mode, so that possible in-depth gradients are detected. Lateral inhomogeneities in the chemical composition and structure of the thin mesoporous films are also identified by applying the same methods in the line-scan or mapping mode, which can be further combined with in-depth sputtering for 3D information. The role of the spatial resolution of the analytical methods considered, which can go down well below 100 nm, will be highlighted. T2 - 2024 Spring Meeting of the European Materials Research Society (E-MRS) CY - Strasbourg, France DA - 27.05.2024 KW - Mesoporous KW - Thin films KW - Iridium oxide KW - Titanium oxide KW - Thin film analysis KW - Porosity KW - SIMS KW - Auger electron spectroscopy PY - 2024 AN - OPUS4-60185 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Chemical Nanoscale Analysis of Mesoporous Mixed IrOx-TiOx Thin Films N2 - Porous films play an important role particularly in energy applications like photovoltaics, electrolysis or batteries. Thin film properties such as thickness, chemical composition, crystallinity of the framework, and porosity define the activity of the porous films. The accurate morpho-chemical characterisation of mesoporous thin films is a challenging analytical task which requires the consideration of new analytical approaches based on the combination of data of different methods able to address the structure and chemical composition at the nanoscale. In this contribution we characterise thin mesoporous iridium-titanium mixed oxide film properties by Electron Probe Microanalysis (EPMA) with Energy-Dispersive X-ray Spectroscopy (EDS) at an SEM applied in a dedicated “thin film analysis” approach. Thus, the film mass deposition, film thickness and the film density can be determined. Further, by dividing the measured film density to an assumed (theoretical) metal oxide framework (skeletal) density, the thin film porosity can be extracted, too. In order to assess the homogeneity of the thin film properties like the chemical composition, Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) and Auger Electron Spectrometry are applied in the depth profiling mode, so that possible in-depth gradients are detected. Lateral inhomogeneities in the chemical composition and structure of the thin mesoporous films are also identified by applying the same methods in the line-scan or mapping mode, which can be further combined with in-depth sputtering for 3D information. The role of the spatial resolution of the analytical methods considered, which can go down well below 100 nm, will be highlighted. T2 - MaterialsWeek 2024 CY - Limassol, Cyprus DA - 17.06.2024 KW - Thin films KW - Mesoporous KW - IR oxide KW - Ti oxide KW - Porosity PY - 2024 AN - OPUS4-60452 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Matthews, Lauren T1 - Approaches to Surface Analysis of Modified Quartz Nanopipettes N2 - Nanopipettes are a type of solid-state nanopore with needle-like geometry. Their applications range from imaging, sensing, diagnostics, and use as injectors. The response of nanopipette sensors is highly dependent on the size, geometry and chemical properties of the sensing region. As they are increasingly tuned and modified for specific analytes, a better understanding of the surface chemistry and morphology of the inner channel is necessary. With the aim of developing a comprehensive approach for characterisation of such nanopipettes, this research focuses on combining surface-sensitive analysis methods with advanced sample preparation techniques. Quartz substrates were modified by gas phase silanization, a well-utilised technique in the field to enhance performance of nanopipettes, and further functionalised with a metal bis thiolate complex, to aid in chemical analysis. The sample characterisation involved scanning electron microscopy (SEM), low-energy dispersive x-ray spectroscopy (EDX), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and Auger electron spectroscopy (AES). Using focused ion beam (FIB) milling under gentle conditions, the inner surface of quartz nanopipettes was exposed whilst preserving the integrity of the overall structure (see figure). Owing to the challenging analysis conditions, modification and analysis of flat quartz substrates has been performed in parallel for optimisation purposes. The results demonstrate the first steps towards full characterisation of nanopipettes at the nanoscale, notably with access to the inner channel. The methods used here can be applied to gain further understanding of the response of these sensors to complex analytes and allow for the study of different surface functionalisations at the all-important sensing region. T2 - European Conference on Applications of Surface and Interface Analysis (ECASIA 2024) CY - Gothenburg, Sweden DA - 09.06.2024 KW - Quartz nanopipettes KW - Nanopipette modification KW - Silanization KW - Surface analysis KW - Focussed ion beam PY - 2024 AN - OPUS4-60447 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Graphene Flagship - Achievements and the way forward N2 - The activities of the Graphene in the field of standardization will be summarized. The future activities of the Graphene Flagship CSA which was established recently will be presented with the focus on future challenges in standardization and regulation of graphene and other 2D materials. T2 - Harmonisation & Standardisation of Test Methods for Nano- and Advanced Materials CY - Online meeting DA - 22.11.2023 KW - 2D materials KW - Regulation KW - Standardization PY - 2023 UR - https://macrame-project.eu/macrame-meetings-workshops/ws_hamonisation_standardisation_2023/ AN - OPUS4-59497 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Matthews, Lauren T1 - Breaking the Wall of Rapid Diagnostics N2 - In this short presentation the diagnostics, biomarkers and analysis are interrelated. The specificity and sensitivity of the DNA structures as well as the high-throughput option of the nanopore sensing are discussed. T2 - Falling Walls Lab Berlin-Adlershof CY - Berlin, Germany DA - 21.09.2023 KW - Nanopipettes KW - Sensing KW - Diagnosis KW - DNA structures PY - 2023 AN - OPUS4-60450 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Salzmann, Christoph A1 - Pellegrino, Francesco A1 - Hodoroaba, Vasile-Dan T1 - STEM-in-SEM versus SE-InLens-type-SEM as a Reliable Analytical Pair-Tool for Measurement of Nanoparticle Size and Shape Distribution N2 - Following points are addressed in this contribution: Advantages of correlative analysis in electron microscopy; Measurement principle of the different electron microscopy modes used; Presentation of the nanomaterials used for this study; Role of sample preparation; and, with particular description, the Sequence kV-variation with InLens SE & transmission SEM detection of the same field-of-view. KW - Nanoparticles KW - Electron microscopy KW - Metrology KW - Particle size distribution PY - 2024 DO - https://doi.org/10.1093/mam/ozae044.308 VL - 30 IS - Supplement_1 SP - 650 EP - 651 PB - Oxford University Press (OUP) AN - OPUS4-61042 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Salzmann, Christoph A1 - Heilmann, Maria A1 - Pellegrino, Francesco A1 - Durand, Bénédicte A1 - Taché, Olivier A1 - Zurutuza, Amaia A1 - Hodoroaba, Vasile-Dan T1 - Ongoing International Interlaboratory Comparisons on Size, Shape and (Relative) Concentration of Complex Nanoparticles under the Pre-Standardization Platform of VAMAS N2 - An overview with the basics of size and shape measurement of particles and 2D structures according to established methodologies (and popular imaging processing software packages) with imaging techniques is given. Main descriptors are explained based on case studies with ongoing interlaboratory comparisons under the pre-standardisation platform of VAMAS. KW - VAMAS KW - Interlaboratory comparison KW - Imaging KW - Size distribution KW - Particle concentration KW - 2D materials PY - 2024 DO - https://doi.org/10.1093/mam/ozae044.319 VL - 30 IS - Supplement 1 SP - 669 EP - 670 PB - Oxford University Press (OUP) AN - OPUS4-61183 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Report VAMAS/TWA 37 "Quantitative Microstructural Analysis" & Liaison with ISO/TC 202 "Microbeam Analysis" N2 - The progress in activities on Quantitative MicroStructural Analysis under VAMAS/TWA 37 is reviewed. Particularly the liaison with the new projects within the ISO technical committee TC 202 Microbeam Analysis is presented and discussed with respect to the identification and launching corresponding VAMAS projects. The ongoing projects "Development of guidelines for reproducible TEM specimen preparation by FIB processing", "Measurement of dislocation density in metallic materials by Transmission Electron Microscope (TEM)", "Repeatability of high angular resolution electron backscatter diffraction (HR-EBSD) analysis for elastic strain measurements", and "Measurement of grain size and distribution of nanocrystalline nickel by using Transmission Kikuchi Diffraction (TKD) in SEM" are presented in detail. T2 - Versailles Project on Advanced Materials and Standards (VAMAS) 49th Steering Committee Meeting CY - Rio de Janeiro, Brazil DA - 23.09.2024 KW - VAMAS KW - Interlaboratory comparison KW - Microbeam Analysis KW - FIB KW - SEM KW - TEM KW - Sample preparation PY - 2024 UR - www.vamas.org/twa37/index.html AN - OPUS4-61388 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schusterbauer, Robert T1 - Correlative chemical imaging to reveal the nature of different commercial graphene materials N2 - Since the original report in 2004 by Novoselov and Geim, Graphene gained incredible attention due to its fascinating properties. In the past 20 years, the synthesis and functionalization of graphene has evolved significantly[3]. Different synthesis techniques were developed which led to other graphenerelated materials such as graphene oxide (GO) or elemental-doped graphene. Further chemical functionalization can enhance but also alter or reduce specific properties of the graphene. To reveal the nature of these materials a proper physico‑chemical characterization with different analytical techniques is crucial. Single-layer GO flakes kindly provided by Graphenea (Spain) were prepared for systematic image analysis. These flakes were disposed on an alignment-marked SiO2 substrate and correlatively imaged by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and Raman spectroscopy. The high lateral resolution and/ or extreme surface sensitivity of the mentioned techniques is necessary to explore monolayers. The ToF-SIMS images match well with the SEM and AFM images and provide information about the chemistry. With 2D Raman spectroscopy it is possible to differentiate between the number of stacked single-layer flakes. This is visualized in a 3D image (Figure b). Well-defined GO flakes could be used as a reference material for imaging of graphene-like structures but also of other types of 2D materials. In addition to these monolayer GO flakes, commercial graphene-containing inks (Haydale) with a more complex morphology were also correlatively imaged. ToF-SIMS and SEM images were merged to identify the origin of different chemical fragments. The findings correlate closely with the expectation that the specific functionalizations (with fluorine and nitrogen as marker elements) are present only on the graphene flakes as presumed from the SEM images. Energy-dispersive X-ray spectroscopy (EDX) supports these results, yet with a much lower sensitivity compared to ToF-SIMS. T2 - ECASIA 2024 CY - Gothenburg, Sweden DA - 09.06.2024 KW - Correlative imaging KW - ToF-SIMS KW - SEM KW - Graphene oxide flakes KW - Raman PY - 2024 AN - OPUS4-60680 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Standardisation needs for regulatory testing of graphene and related 2D materials. phy-chem properties N2 - The main properties and main methods which are needed for the physico-chemical characterisation of graphene related 2D materials are discussed. As expample for standardization, protocols for the measurement of the chemical composition with XPS are discussed. The results of an interlaboratory comparisons led to new recommendations for the reliable measurments protocols. T2 - Materials Week 2024 CY - Limassol, Cyprus DA - 17.06.2024 KW - Standardisation KW - Functionalized graphene KW - Interlaboratory comparison KW - Endpoints PY - 2024 AN - OPUS4-60537 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Knigge, Xenia A1 - Radnik, Jörg T1 - Advanced materials for the energy transition N2 - The climate crisis is the burning issue of our time. In order to avert the impending consequences, global efforts are being made in a wide variety of social and scientific fields. This report looks at a small part of these efforts, a technical aspect, namely the question of which AdMa are currently considered in techniques to support the energy transition. AdMa, i.e. materials that are rationally designed to have new or enhanced properties, and/or targeted or enhanced structural features, are used in all sectors of the energy transition. Questions of energy generation, storage and saving are considered here. This report is based on literature research and contains a general compilation of various AdMa that are used in the energy transition or are being researched for this purpose. From this compilation, ten materials that are considered particularly relevant for various reasons were selected and examined in more detail in relation to their use. The specific question here lies in the conflicting objective that the development of technologies for the energy transition is welcomed, but the use of AdMa may entail possible challenges in view of chemical safety as well as sustainability and circular economy. KW - Energy generation KW - Energy saving KW - Eneergy storage KW - Energy transportation PY - 2025 DO - https://doi.org/10.60810/openumwelt-7853 SN - 1862-4804 VL - 83 SP - 1 EP - 64 PB - Umweltbundesamt CY - Dessau-Roßlau AN - OPUS4-63529 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Liaison between ISO/TC 202 Microbeam Analysis and VAMAS/TWA 37 Quantitative Microstructural Analysis N2 - The liaison between ISO/TC 202 Microbeam Analysis and VAMAS/TWA 37 Quantitative Microstructural Analysis and other TWAs since the last Annual Meeting of ISO/TC 202 is reported. The VAMAS/TWA 37 projects initiated in the last year and the new ones in the planing phase are highlighted with technical and organisational details. T2 - 31st Plenary Meeting of ISO/TC202 Microbeam Analysis CY - Tokio, Japan DA - 29.10.2024 KW - ISO TC 202 KW - Microbeam Analysis KW - Interlaboratory comparison KW - VAMAS KW - Standardisation PY - 2024 AN - OPUS4-61513 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - John, Elisabeth T1 - Exploring the SIMS Matrix Effect in High-Entropy Alloy Thin-Films N2 - Compared with traditional alloys, which typically consist of one or two main elements and small amounts of secondary elements, High Entropy Alloys (HEA) are characterized by the presence of multiple principal elements in almost equal proportions. This unique composition results in a high degree of disorder at the atomic level, leading to exceptional mechanical, physical, and often unexpected properties. HEAs have garnered significant attention in materials science and engineering due to their potential applications in a wide range of industries, from aerospace and automotive to electronics and renewable energy. Analyzing materials composed of multiple elements with spectroscopic techniques such as X-ray Photoelectron Spectroscopy (XPS), Auger-Electron Spectroscopy (AES) or Electron Probe Microanalysis (EPMA), can be challenging due to spectral overlap. This challenge reaches its peak if neighboring 3d elements are present, as it is the case for the famous Cantor alloy which is composed of Cr, Mn, Fe, Co and Ni. Moreover, each analytical method introduces its own set of challenges, e.g., the strong secondary fluorescence effect for neighbor elements in EPMA, thus, making the accurate elemental quantification in such materials difficult. If the material is available as thin film, additional constraints are inherently present. To provide a reference material for these analytical challenges HEAs are excellent candidates. Currently, there is no thin film reference available containing more than two elements. Our goal is to prepare thin films with a homogeneous thickness and defined, homogenous chemical composition to be analyzed by various methods dedicated to surface analysis. ToF-SIMS is an excellent method for the (3D) analysis of thin films, however due to the dependence of element ion yield on the surrounding chemical state i.e., the matrix effect, it is considered a non-quantitative method. In HEAs the elements are each present in a homogenous matrix which makes these materials interesting for investigation of the matrix effect. Moreover, we evaluate methods to minimize the disturbances of oxygen enhancement during the beginning of the sputter analysis and the effect of recoil mixing at the film/substrate interface with the aim to measure accurate depth profiles. T2 - SIMS 24 CY - La Rochelle, France DA - 09.09.2024 KW - High-entropy alloy KW - ToF-SIMS KW - Matrix Effect PY - 2024 AN - OPUS4-62511 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilling, Markus T1 - Towards Structured Data Spaces: Prototypical Application of Semantic Technologies as a Driver for Innovation in Materials Science N2 - In the pursuit of advancing development and digitalization within materials science, ensuring quality assurance, interoperability, and adherence to FAIR principles is significant. To address these aspects, semantic technologies are employed for storage, processing, and contextualization of data, offering machine-actionable and human-readable knowledge representations crucial for data management. This presentation showcases the prototypical application of generic approaches of knowledge representation in materials science. It includes the design and documentation of graph patterns that may be compiled into rule-based semantic shapes. The development and application of the PMD Core Ontology 3.0 (PMDco 3.0) tailored for materials science is highlighted. Its integration into daily lab life is demonstrated through its functional incorporation into electronic lab notebooks (ELN). Examples of material processing and standardized mechanical testing illustrate how knowledge graph operations enhance ELN capabilities, providing a generalizable unified approach for managing diverse experimental data from different sources with automation potentials. T2 - TMS Specialty Congress 2025 CY - Anaheim, CA, USA DA - 15.06.2025 KW - Semantic Data KW - Data Integration KW - Digitalization KW - Data Interoperability KW - Plattform MaterialDigital PY - 2025 AN - OPUS4-63401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Challenges in Correlative imaging of Advanced Materials N2 - Newly developed methodical approaches with an emphasis on correlative imaging analysis of morphology and chemistry of nanomaterials will be presented. Correlative imaging by high-resolution SEM with STEM-in-SEM as well as with EDS, and further with AFM, or with the new technique TKD (Transmission Kikuchi Diffraction) will be explained on various examples of nanostructures, both as starting materials and as embedded/functionalized nanoparticles in products. The unique analytical benefits of the Auger electron probe as a veritable nano-tool for the local surface chemistry will be highlighted. Examples of hybrid analysis of the bulk of nanomaterials by X-ray Spectroscopy and the highest surface-sensitive methods XPS and ToF-SIMS as advanced surface characterization methods available in the Competence Centre nano@BAM will be showed. Particularly for the spatially resolved analysis of the chemistry of nanostructures, such in-depth and lateral gradients of chemistry within mesoporous thin layers, or the completeness of the shells of core-shell nanoparticles, the latter methods are inherent. Other dedicated developments like approaches for the quantitative determination of the porosity of thin mesoporous layers by electron probe microanalysis (EPMA) with SEM or the quantitative determination of the roughness of particle surface by high-resolution imaging with electron microscopy will be also presented. T2 - Workshop: Harmonisation & Standardisation of Test Methods for Nano- and Advanced Materials CY - Online meeting DA - 18.11.2024 KW - Imaging KW - Advanced materials KW - Correlative imaging KW - Nanomaterials KW - Electron microscopy KW - ToF-SIMS PY - 2024 UR - https://macrame-project.eu/macrame-meetings-workshops/2nd-joint-online-workshop-harmonisation-standardisation-of-test-methods-for-nano-and-advanced-materials/ AN - OPUS4-61858 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fernandez-Poulussen, D. A1 - Hodoroaba, Vasile-Dan T1 - Holistic, reliable and practical Characterization Framework for Graphene Family Materials, a correlated approach including Imaging based techniques N2 - ACCORDs is an Horizon Europe project working in the development of an imaging-based characterization framework (ACCORDs framework) for the holistic correlative assessment of Graphene Family Materials (GFMs) as a representative of 2D nanomaterials (NMs) to assess and predict 2D NMs health and environmental risks. The ACCORDs framework will operationalise safe and sustainable by design (SSbD) strategies proposed in past or ongoing H2020 projects or within OECD by correlating low-, medium-, and high-resolution physico-chemical-biological imaging-based methods with non-imaging methods in a tiered approach. ACCORDs will deliver the ACCORDs framework and user guidance, new imaging-based characterisation methods, reference in vitro tests, new reference 2D NMs for different matrices, a new minimum information reporting guideline for FAIR data sharing and reuse of images as well as an atlas with reference images for diagnostics of compromised safety of GFMs/GFM products. The new guidelines and standard proposals will be submitted to standardisation bodies to allow creation of regulatory ready products. The novelty of ACCORDs is in translating the principles of medical imaging-based diagnostics to 2D material hazard diagnostics. ACCORDs will accelerate industrial sectors in the area of aviation, marine construction, drone production, flexible electronics, photovoltaics, photocatalytics and print inks-based sensors. The value ACCORDs proposes to the graphene industry are practical, easy, imaging-based tools for GFM quality monitoring next to the production line with a possibility to be correlated with advanced highresolution imaging characterization methods in case hazard i.e. deviation from controls (benchmark values) are diagnosed. The ACCORDs framework and tools will contribute to the European Green Deal by addressing the topic: “Graphene: Europe in the lead” and to a new European strategy on standardization, released on 2nd February, 2022 T2 - Joint Regulatory Risk Assessors Summit – Advancing Safety & Sustainability Assessments of Advanced Materials CY - Paris, France DA - 19.06.2025 KW - Graphene-related 2D materials (GR2M) KW - Imaging KW - SSbD KW - ACCORDs PY - 2025 UR - https://macrame-project.eu/macrame-meetings-workshops/jointrras/#Agenda AN - OPUS4-63660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Investigation of Fe-Ni-O nanoparticles for water splitting N2 - This study investigates the effect of varying iron-to-nickel ratios on the catalytic performance of Fe-Ni oxide nanoparticles (NPs) for the oxygen evolution reaction (OER). Addressing the issue of high energy wastage due to large overpotentials in OER, we synthesized and characterized different NP catalysts with different Fe: Ni oxide ratios. Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDS), and X-ray Diffraction (XRD) were employed to determine the morphology, elemental and phase composition of the NPs. Furthermore, in-depth profiling with X-rayPhotoelectron Spectroscopy (XPS) and Hard X-ray Photoelectron Spectroscopy (HAXPES) revealedthat iron predominantly exists as oxide, while nickel exhibits both metallic and oxidic forms depending on the Fe content. XPS indicated an enrichment of iron at the NP surface, whereas HAXPES and EDSdata agreed on the bulk stoichiometry. T2 - PhI European User Meeting 2025 CY - Eibelstadt, Germany DA - 29.04.2025 KW - Oxygen evolution reaction KW - In depth analysis KW - (Hard) X-ray Photoelectron Spectroscopy PY - 2025 AN - OPUS4-63334 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Methodological Challenges and Gaps: Physico-Chemical Characterisation N2 - The methodological challenges and gaps in the physico-chemical characterisation of graphene related 2D Materials (GR2M) are discussed. Solutions for filling the gaps are presented. T2 - OECD Graphene Expert Workshop CY - Paris, France DA - 26.11.2024 KW - Graphene related 2D materials KW - Structure activity relationsships KW - Classification PY - 2024 AN - OPUS4-61920 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fagan, Jeffrey A1 - Hodoroaba, Vasile-Dan T1 - VAMAS TWA Nanoparticle Populations Projects 15 and 16 N2 - The progress in the VAMAS Project #15 "Measurement of particle size and shape distribution of bipyramidal titania including deposition from liquid suspension" within TWA 34 Nanoparticle Populations is presented with highlight of the following points: - Determine and compare particle size and shape distribution by means of electron microscopy (SEM, TEM, STEM-in-SEM), atomic force microscopy (AFM) and small angle X-ray scattering (SAXS). - Determine uncertainty induced by deposition protocol from liquid suspension with comparison to known values from a prior ILC with already deposited nanoparticles on TEM grids. - Provide comparative validation of protocols for the techniques other than TEM. Further, the VAMAS/TWA 34 Project #16 "Measurement of (relative) number concentration of bimodal silica nanoparticles including deposition from liquid suspension" is presented. Follwowing points are discusssed: - Validate the performance of imaging methods to measure the relative number concentration by electron microscopy (SEM, TEM) and atomic force microscopy (AFM) and two modes of bimodal (30 and 60 nm) silica nanoparticles - Validate the performance of small angle X-ray scattering (SAXS) for the traceable measurement of the number concentration of the two modes. T2 - Versailles Project on Advanced Materials and Standards (VAMAS) 49th Steering Committee Meeting CY - Rio de Janeiro, Brazil DA - 23.09.2024 KW - VAMAS KW - Nanoparticles KW - Nanoparticle size and shape distribution KW - Particle number concentration KW - Interlaboratory comparison KW - Standardisation PY - 2024 UR - http://www.vamas.org/twa34/index.html AN - OPUS4-61422 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fagan, J. A1 - Hodoroaba, Vasile-Dan T1 - VAMAS TWA 34 Nanoparticle Populations Combined Projects P15 and P16 N2 - The progress in the VAMAS Project #15 "Measurement of particle size and shape distribution of bipyramidal titania including deposition from liquid suspension" within TWA 34 Nanoparticle Populations is presented with highlight of the following points: - Determine and compare particle size and shape distribution by means of electron microscopy (SEM, TEM, STEM-in-SEM), atomic force microscopy (AFM) and small angle X-ray scattering (SAXS). - Determine uncertainty induced by deposition protocol from liquid suspension with comparison to known values from a prior ILC with already deposited nanoparticles on TEM grids. - Provide comparative validation of protocols for the techniques other than TEM. Further, the VAMAS/TWA 34 Project #16 "Measurement of (relative) number concentration of bimodal silica nanoparticles including deposition from liquid suspension" is presented. Follwowing points are discusssed: - Validate the performance of imaging methods to measure the relative number concentration by electron microscopy (SEM, TEM) and atomic force microscopy (AFM) and two modes of bimodal (30 and 60 nm) silica nanoparticles - Validate the performance of small angle X-ray scattering (SAXS) for the traceable measurement of the number concentration of the two modes. - Discussion of sample preparation issues - Publication of the results in 2026 T2 - Versailles Project on Advanced Materials and Standards (VAMAS) 50th Steering Committee Meeting CY - London, United Kingdom DA - 14.09.2025 KW - VAMAS KW - Interlaboratory comparison KW - Particle size and shape distribution KW - Particle number concentration KW - Standardisation PY - 2025 UR - https://www.vamas.org/twa34/index.html AN - OPUS4-64234 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - VAMAS Regional Report Advanced Materials Germany 2025 N2 - Regional standardisation activities and how VAMAS can help in any way to promote activities are reported. Activities related to organisational updates, government initiatives/priorities (especially related to Advanced Materials), details of any strategy documents publicly available, networks within Germany and how we engage are presented. T2 - Versailles Project on Advanced Materials and Standards (VAMAS) 50th Steering Committee Meeting CY - London, United Kingdom DA - 14.09.2025 KW - VAMAS KW - Interlaboratory comparison KW - Advanced materials KW - Standardisation PY - 2025 AN - OPUS4-64232 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stockmann, Jörg Manfred T1 - A new XPS test material for more reliable surface analysis of microstructures N2 - Small-area XPS analysis is one of the most popular and powerful methods for analysing the surface of features in the micro-range. When measuring microstructures, the ques-tion arises whether the measuring point is really located at the point intended to be ana-lysed. Information in a measured spectrum might originate within the field of view (FoV) on the surface of the sample, from outside the FoV, or even from inherent contamination. To ensure that small structures can be measured correctly regardless of user and instru-ment, certain instrument and sample settings must be known and selected correctly: beam and aperture size as well as the aperture settings and the approximate dimensions of the structure to be analysed. This is the only way to ensure that the information in the spectrum originates only from the FoV on the analysed structure. To test the performance of the XPS instruments, a dedicated test material was developed that consists of a gold surface on which 8 circles and 8 squares of chrome are incorpo-rated using a masking process, so that the Au substrate and the Cr structure surfaces are in the same surface plane. In order to be able to test as many as possible instruments from different manufacturers, the structures have been designed with a size ranging from 300 µm down to 7 µm. The layout of the test material has been optimised in regard of the handling. The structures are arranged along lines instead of a circumference, marking arrows around the smaller structures (≤50 µm) are added, and the lithography mask is optimised regarding edge and diffraction effects. Furthermore, the manufacturing process was changed from electron-beam deposition to mask lithography due to costs reasons. The structures on the test material were measured with a metrological SEM to determine their accurate dimensions and check the repeatability of the manufacturing process. XPS investigations with a Kratos AXIS Ultra DLD and an ULVAC-Phi Quantes demonstrates the suitability of this new test material for measuring the analysed area. T2 - ECASIA 2024 CY - Gothenburg, Sweden DA - 09.06.2024 KW - Small-area XPS KW - Test material KW - Field of view KW - Imaging PY - 2024 AN - OPUS4-60539 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Matthews, Lauren T1 - Approaches to Surface Analysis of Modified Quartz Nanopipettes N2 - Nanopipettes are a type of solid-state nanopore with needle-like geometry. Their applications range from imaging, sensing, diagnostics, and use as injectors. The response of nanopipette sensors is highly dependent on the size, geometry and chemical properties of the sensing region. As nanopipettes are increasingly tuned and modified for specific analytes, a better understanding of the surface chemistry and morphology of the inner channel is necessary. For exploring these effects, quartz nanopipettes were modified by gas phase silanization, a well-utilised technique in the field to enhance performance of nanopipettes, and further functionalised with a metal bis thiolate complex, to aid in chemical analysis. The inner channel of the sensing region was exposed with focused ion beam (FIB) milling as a dedicated sample preparation method for nanoscale surface analysis. The sample characterisation involved scanning electron microscopy (SEM), Auger electron spectroscopy (AES) and low-energy energy dispersive x-ray spectroscopy (EDX). The results demonstrate the first steps towards full characterisation of nanopipettes at the nanoscale, notably with access to the inner channel. The methods used here can be applied to gain further understanding of the response of these sensors to complex analytes, and allow for the study of different surface functionalisation at the all-important sensing region. T2 - 2024 Spring Meeting of the European Materials Research Society (E-MRS) CY - Strasbourg, France DA - 27.05.2024 KW - Nanopipettes KW - FIB KW - Surface analysis KW - Surface modification KW - Silanisation PY - 2024 AN - OPUS4-60449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heilmann, Maria A1 - Hodoroaba, Vasile-Dan T1 - Project 16 Measurement of (relative) number concentration of bimodal silica nanoparticles including deposition from liquid suspension N2 - The progress of the VAMAS Project 16 "Measurement of (relative) number concentration of bimodal silica nanoparticles including deposition from liquid suspension" in TWA 34 Nanoparticle Populations is presented. Follwowing points are discusssed: - Validate the performance of imaging methods to measure the relative number concentration • electron microscopy (SEM, TEM) and atomic force microscopy (AFM) • two modes of bimodal (30 and 60 nm) silica nanoparticles - Validate the performance of small angle X-ray scattering (SAXS) for the traceable measurement of the number concentration of the two modes. T2 - VAMAS Regional Workshop 2023 - What can pre-normative research do for industry? CY - Online meeting DA - 24.01.2023 KW - Nanoparticles KW - VAMAS KW - Inter-laboratory comparison KW - SiO2 KW - Electron microscopy KW - AFM PY - 2023 UR - https://www.bam.de/Content/EN/Events/2023/2023-01-24-vamas-regional-workshop.html AN - OPUS4-57221 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - del Giorgio, Elena T1 - Visible and NIR emissive lanthanide(III) surfaces for new luminescent materials N2 - Luminescent lanthanides(III) offer exceptional optical properties that can overcome issues often encountered with other fluorophores (e.g. organic dyes). Their long lifetimes up to milliseconds, low photobleaching and sharp and characteristic emission peaks make the lanthanides extremely valuable for the development of advanced luminescent materials. Previous work on Ru(II) and Ir(III) gold surfaces further highlights the potential of employing the luminescence of metal complexes for the fabrication of sensing platforms and devices. Here, we incorporate visible and NIR-emitting lanthanide(III) complexes Ln2L3 (Ln = Eu(III), Nd(III), Yb(III)) to gold and plasmonic surfaces, translating the unique optical properties of the lanthanides(III) to practical devices. The Ln2L3 complexes are deposited on the surfaces with different methods, ranging from polymer aided physisorption to the covalent attachment on the gold surface. Furthermore, we exploit the high sensitivity to the coordination environment of lanthanides(III) to design and prepare a sensing platform. T2 - 17th Conference on Methods and Applications in Fluorescence (MAF 2022) CY - Göteborg, Sweden DA - 11.09.2022 KW - Luminescent materials KW - Lanthanide(III) KW - Surface morphology KW - AFM KW - SEM/EDS PY - 2022 UR - https://maf2022.com/ AN - OPUS4-56126 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hertwig, Andreas T1 - Normung in der Oberflächen-und Schichttechnik N2 - Report über Normungsaktivitäten im Bereich der Messtechnk an Oberflächen und dünnen Schichten. Übersicht über Methoden und Vorstellung von laufenden Projekten mit Bezug zur Normung T2 - PlasmaGermany Herbstmeeting 2022 CY - Bielefeld, Germany DA - 07.11.2022 KW - Oberflächenmesstechnik KW - Spektroskopie KW - Ellipsometrie KW - XPS KW - Dünne Schichten PY - 2022 AN - OPUS4-56483 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hodoroaba, Vasile-Dan T1 - External Liaison Report ISO/TC 202 'Microbeam Analysis' to ISO/TC 229 'Nanotechnologies' N2 - The liaison report from the ISO Technical Committee ISO/TC 202 'Microbeam Analysis' for the November 2022 ISO/TC 229 Nanotechnologies Plenary Meeting Nanotechnologies Liaison Coordination Group (NLCG) is provided. Essential Information such as newly published standards and projects in develeopment relevant for ISO/TC 229 resulted from the progress within the last year and additional comments on behalf of ISO/TC 202 are included in the report. KW - ISO/TC 202 KW - ISO/TC 229 KW - VAMAS KW - Nanotechnologies KW - Microbeam Analysis KW - Standardisation PY - 2022 SP - 1 EP - 4 CY - ISO, Geneva, CH AN - OPUS4-56734 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Nanoparticle Populations N2 - Two new projects P15 Measurement of particle size and shape distribution of bipyramidal titania including deposition from liquid suspension and P16 Measurement of (relative) number concentration of bimodal silica nanoparticles including deposition from liquid suspension have been started at VAMAS/TWA 34 under the lead of BAM. First results are presented and discussed. T2 - Versailles Project on Advanced Materials and Standards (VAMAS) 47th Steering Committee Meeting CY - Turin, Italy DA - 18.10.2022 KW - VAMAS KW - Nanoparticles KW - Inter-laboratory comparison KW - Particle size distribution KW - Nanoparticle concentration PY - 2022 AN - OPUS4-56196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - (hard) x ray photoelectron spectroscopy as tool in nano-analytics N2 - Selected samples are used to show, that photoelectron spectroscopy is an important tool for measuring nano-objects, especially for determing the chemical composition and structure on the nanosacle. XPS with different energies offers new possibilities in depth-profiling. T2 - SFB 1073 Colloquium CY - Göttingen, Germany DA - 22.02.2024 KW - X-ray photoelectron spectroscopy KW - Core-shell nanoparticle KW - Graphene related 2D materials PY - 2024 AN - OPUS4-59589 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Liaison of ISO/TC 202 Microbeam Analysis with VAMAS/TWA 37 Quantitative Microstructural Analysis N2 - The progress in activities on Microbeam Analysis under VAMAS/TWA 37 is reviewed. Particularly the liaison with the new projects within the ISO technical committee TC 202 is presented and discussed with respect to the identification and launching corresponding VAMAS projects. The ongoing project "FIB sample processing for TEM" is presented in detail. T2 - 30th Meeting of ISO/TC 202 Microbeam Analysis CY - Berlin, Germany DA - 22.11.2023 KW - VAMAS KW - ISO/TC 202 KW - Microbeam Analysis KW - Standardisation KW - Electron microscopy KW - FIB PY - 2023 AN - OPUS4-58984 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pellegrino, F. T1 - Safe-by-Design Synthesis of 2D Materials N2 - The use of a dedicated approach: DoE for synthesis + characterization + Chemometric Analysis, is a valuable method for the safe-by-design synthesis of several types of materials for large-scale application in catalysis, energy harvesting, biomedical and environmental applications, etc. This approach is not only related to the material synthesis, but can be expanded to any type of molecules/material, with relevant saving of solvents, energy and times. T2 - Congress of the Environment and Cultural Heritage - Section of Italian Chemistry Society CY - Ischia, Italy DA - 28.09.2023 KW - Safe-by-design KW - 2D materials KW - Synthesis KW - Chemometric analysis PY - 2023 UR - https://www.congressodabc.it/ AN - OPUS4-59780 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Terborg, R. A1 - Procop, Mathias T1 - Theoretical calculation and experimental determination of x-ray production efficiencies for copper, zirconium, and tungsten N2 - The X-ray intensities of the K-, L- and M-lines of copper, zirconium and tungsten have been measured with an energy-dispersive X-ray spectrometer of known efficiency as function of photon energy. X-ray production efficiencies were determined from the measured intensities for Kα- and L-series of Cu and Zr and for the L- and M-series of W. These data were compared to calculated X-ray production efficiencies based on the widely used matrix correction models of Pouchou and Pichoir (XPP) and Bastin (PROZA96). Our results indicate that a replacement of the stopping power in the PROZA96 algorithm by expressions of Joy and Jablonski has only a minor influence on the calculated X-ray production efficiencies. In contrast, the modifications of the ionization cross-section show a stronger effect. We replaced the ionization cross-sections for K lines of the PROZA96 algorithm with different models. The results for L- and M-Lines are different. For the L-lines of Cu the original XPP and PROZA96 models show the best agreement while using the Bote cross-sections result in an overestimation. For the Zr-L and W-L1, -L2, -L3 X-ray production efficiencies, the Bote cross-sections lead to a significant improvement compared to all other models. The original XPP model represents the best agreement for the M5 efficiencies but underestimates the M4 efficiencies. There is no superior model or modification because the parameter sets in the models need to be aligned to each other. However, using the ionization cross-sections of Bote, which are based on quantum mechanical calculations, show promising results in many cases. KW - X-ray production efficiency KW - EPMA KW - Copper KW - Zirconium KW - Tungsten PY - 2023 DO - https://doi.org/10.1093/micmic/ozad067.110 SN - 1435-8115 VL - 29 IS - Supplement 1 SP - 245 EP - 246 PB - Oxford University Press CY - Oxford AN - OPUS4-58339 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hodoroaba, Vasile-Dan T1 - Delivering Impact - A new ISO standard on the identification of nanoparticles N2 - Nanoparticles (NPs) are tiny – around 1 to 100 billionths of a meter – and can have different chemistries and behaviours than the same material of larger size. This property has led to advances in a wide range of industries, but it can also confer toxicity. Size measurements are the main way NPs are identified but a lack of standardised methods for identifying ones with complex shapes has hindered evaluation of their potential harm. KW - Nanoparticles KW - Standardisation KW - Particle size distribution KW - nPSize KW - ISO 21363 PY - 2024 UR - https://www.euramet.org/casestudies/casestudiesdetails/news/default-c3b26209e8 SP - 1 EP - 2 PB - EURAMET CY - Braunschweig AN - OPUS4-59626 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Corrao, Elena A1 - Gouasmi, Meriem A1 - Sordello, Fabrizio A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Joerg A1 - Maurino, Valter A1 - Pellegrino, Francesco T1 - Tailoring TiO2 Morphology and Surface Chemistry for Optimized Photocatalytic Activity in rGO Hybrids N2 - TiO2–reduced graphene oxide (rGO) hybrids were investigated in this study to elucidate how TiO2 morphology and surface chemistry govern charge-transfer pathways and, ultimately, reaction selectivity. Three anatase TiO2 nanostructures were compared: bipyramids predominantly exposing {101} facets (bipy) and two nanosheet-like samples enriched in {001} facets, either fluorinated (n-sh) or thermally defluorinated and {101}-enriched (n-sh_873K). A constant rGO loading (2 wt.%) was introduced via in situ hydrazine reduction of graphene oxide in the presence of TiO2. Photocatalytic activity was evaluated under Xe-lamp irradiation in two model reactions probing oxidative and reductive pathways: phenol degradation and H2 evolution using formic acid as a scavenger. rGO systematically enhanced phenol degradation for all morphologies, with bipy+rGO showing the highest activity. In contrast, H2 evolution was consistently suppressed upon rGO incorporation across all TiO2 samples, although the bipyramidal morphology remained the most active within each series. These results highlight that facet exposure and surface functionalization dictate the beneficial or detrimental role of rGO depending on the targeted photocatalytic pathway. KW - Photocatalytic activity KW - Reduced graphene oxide KW - TiO2 KW - Surface chemistry KW - 2D materials PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653476 DO - https://doi.org/10.26434/chemrxiv-2026-65917 SP - 1 EP - 12 PB - American Chemical Society (ACS) AN - OPUS4-65347 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Narayanan, M.M. A1 - Nicolai, M. A1 - Prager, J. T1 - C9-a5 - Optimization of Low-Frequency Shear Wave Transducers for Guided Wave Applications N2 - Development of ultrasonic transducers for the excitation of a torsional mode T(0,1) mode in a large pipe of the material typical of actual oil/gas pipelines is discussed. Towards this,16 ultrasonic transducers are designed and fabricated using shear plates of PIC 255 material, backing mass of tungsten-epoxy composite and brass shims as wear plates. The transducers are qualified using Laser Doppler Vibrometry. Then, the transducers are embedded in a springloaded ring and tested on a pipe using a multi-channel ultrasonic system. The results show the successful excitation of T(0,1) mode and it is seen to propagate for distance of 60 m with a good SNR. T2 - 2025 ICU PADERBORN - 9th International Congress on Ultrasonics CY - Paderborn, Germany DA - 21.09.2025 KW - Ultrasonic guided waves KW - Torsional mode KW - Shear PZT plates KW - Ring array transducer design KW - Pipe testing PY - 2025 DO - https://doi.org/10.5162/Ultrasonic2025/C9-a5 SP - 223 EP - 226 PB - AMA Service GmbH AN - OPUS4-65356 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zeipert, H. A1 - Nellius, T. A1 - Schönlau, N. A1 - Wippermann, M. A1 - Claes, L. A1 - Henning, B. A1 - Nicolai, Marcel A1 - Prager, J. T1 - C6-a3 - Monitoring the curing process of adhesive bonds using selective excitation of guided ultrasonic waves N2 - A measurement setup for the selective excitation of guided ultrasonic waves in adhesively bonded plates is introduced. Changes of the dispersive behaviour of the guided waves during the curing process is known to be accompanied by a change in the propagating waves group velocities. The proposed measurement setup is used to monitor that change during the curing process of an aluminium-epoxy-polycarbonate bond. T2 - 2025 ICU PADERBORN - 9th International Congress on Ultrasonics CY - Paderborn, Germany DA - 21.09.2025 KW - Ultrasonic guided waves KW - Selective excitation KW - Non-destructive testing KW - Adhesive bonding KW - Condition monitoring PY - 2025 DO - https://doi.org/10.5162/Ultrasonic2025/C6-a3 SP - 207 EP - 210 PB - AMA Service GmbH AN - OPUS4-65357 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pomorska Gawel, A. A1 - Dąbkowska, M. A1 - Kosior, D. A1 - Batys, P. A1 - Szatanik, A. A1 - Witt, Julia A1 - Özcan Sandikcioglu, Özlem A1 - Michna, A. T1 - Multiscale insights into fibroblast growth factor 23 adsorption on polyelectrolyte layers: From molecular properties to biointerfaces N2 - Fibroblast growth factor 23 (FGF23) is a clinically significant protein hormone regulating phosphate and vitamin D metabolism, with elevated levels linked to chronic kidney disease, cardiovascular disorders, and impaired bone homeostasis. Despite its relevance as both a biomarker and a therapeutic target, its interactions with functional biomaterials remain poorly understood. In this work, we investigate the FGF23 adsorption on polyelectrolyte layers using a combination of theoretical modeling and experimental methods. Theoretical calculations provided insights into the protein's charge distribution and diffusion properties, while experimental measurements quantified its hydrodynamic diameter, electrophoretic mobility, and electrokinetic charge over a broad range of pH values. Microscale thermophoresis revealed quantitative binding affinities of FGF23 to hyaluronic acid, chitosan, and poly(diallyldimethylammonium chloride). Adsorption studies on mica, silica, and polyelectrolyte mono- and bilayers showed that FGF23 binds to both negatively and positively charged substrates, with binding affinities following: hyaluronic acid < poly(diallyldimethylammonium chloride) < chitosan. Desorption occurred more readily from negatively charged surfaces (mica, silica and hyaluronic acid), indicating weaker interactions compared to positively charged layers. These results reveal fundamental aspects of protein –polyelectrolyte interactions and highlight the reversible binding capacity of FGF23 to negatively charged surfaces. Such adsorption behavior provides a physicochemical framework for considering FGF23-polyelectrolyte systems in the design of therapeutic carriers and bioactive materials. However, any direct relevance to wound healing, chronic kidney disease, or cardiovascular disorders remains prospective and requires dedicated biological validation. KW - Molecular dynamics KW - Streaming potential measurements KW - Adsorption KW - Stability KW - Binding affinity PY - 2026 DO - https://doi.org/10.1016/j.ijbiomac.2026.150221 SN - 0141-8130 VL - 341 IS - Part 1 SP - 1 EP - 14 PB - Elsevier B.V. AN - OPUS4-65415 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fareed, Adnan A1 - Rosalie, Julian A1 - Kar, Satyakam A1 - Fähler, Sebastian A1 - Maaß, Robert T1 - Small-scale functional fatigue of a Ni-Mn-Ga Heusler alloy N2 - Functional fatigue of shape-memory alloys is a considerable threat to the reliable service of actuation devices. Here, we demonstrate the essentially degradation-free cyclic phase-transformation behavior of Ni-Mn-Ga microcrystals up to one million stress-driven superelastic cycles. Cyclic dissipation amounts to about 1/5 of the bulk counterpart and remains unaffected during cycling, even after the introduction of dislocation structures via plastic straining. Plastic yielding and the transformation stress largely exceed the known bulk values. However, the transformation-stress is found to depend on plastic pre-straining, which suggests that the size-affected transformation stress is sensitive to the initial defect structure and that it can be tuned by a targeted introduction of dislocations. These findings demonstrate the high suitability of Ni-Mn-Ga as a robust shape-memory alloy in small-scale functional device engineering. KW - Superelasticity KW - Shape-memory alloys KW - Functional fatigue KW - Ni-Mn-Ga PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600695 DO - https://doi.org/10.1016/j.actamat.2024.119988 VL - 274 SP - 1 EP - 10 PB - Elsevier B.V. AN - OPUS4-60069 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Almalla, A. A1 - Hertwig, Andreas A1 - Fischer, Daniel A1 - Özcan Sandikcioglu, Özlem A1 - Witt, Julia T1 - Development of layer-by-layer assembled thin coatings on aluminium alloy AA2024-T3 for high resolution studies of local corrosion processes N2 - The aim of this study is to develop nanometer-thin epoxy-based films on aluminium alloy AA2024-T3 as a model coating system for high resolution corrosion studies. Spin coating was used for the layer-by-layer (LbL) deposition of poly-(ethylenimine) (PEI) and poly([o-cresyl glycidyl ether]-co-formaldehyde) (CNER) bilayers. The film chemistry and the cross-linking process were characterized by means of Fourier-transform infrared spectroscopy (FTIR). Ellipsometric data confirmed the linear increase of film thickness. The potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) results indicate the improvement of the film barrier properties with increasing film thickness. Mapping of the topography and the volta potential was performed by means of scanning Kelvin probe force microscopy (SKPFM). The results indicate the presence of a homogeneous film structure, while the intermetallic phases can still be identified below the coating. The SKPFM Analysis confirmed that the model films are suitable for investigation of corrosion processes at the coating/metal interface. KW - Spectroscopy KW - Coatings KW - Electrochemistry KW - Microscopy KW - Resins PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-514627 DO - https://doi.org/10.1002/app.49826 SN - 0021-8995 VL - 137 IS - 48 SP - e49826-1 EP - e49826-9 PB - Wiley CY - New York, NY AN - OPUS4-51462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Kuchenbecker, Petra A1 - Lindemann, Franziska T1 - Final report proficiency test LS BAM-5.5-2021: Measurement of the particle size distribution of ceramic powders by laser diffraction in accordance with ISO 13320 N2 - This is the final report on the proficiency test (PT) „Measurement of the particle size distribution of ceramic powders by laser diffraction”. The PT was organized by the Federal Institute for Materials Research and Testing (BAM), division 5.5 “Advanced technical ceramics”. The measurements took place from 12/2021 to 03/2022. The aim of the interlaboratory comparison was the proficiency assessment of the participating laboratories. Management and realization of PT were performed in accordance with DIN EN ISO/IEC 17043:2010. The basis of the harmonized measuring procedure and the instructions for the interlaboratory comparison was the standard ISO 13320:2020. The statistical analysis was performed in accordance with DIN ISO 13528:2020 by use of the software PROLab Plus (QuoData GmbH, Dresden, Germany). A group of 44 laboratories from 17 countries participated in the PT. Laser diffraction analyzers produced by 7 different manufacturers were used. The three test materials were commercial products. Overall, the measured characteristic values of the particle distributions (d10, d50 and d90) were in the size range between 0.5 and 25 μm. The final report contains all individual results in an anonymous way. KW - Proficiency test KW - Particle size KW - Laser light scattering PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548640 DO - https://doi.org/10.26272/opus4-54864 SP - 1 EP - 33 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-54864 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hahn, Marc Benjamin T1 - Temperature effects in the Object Oriented Micromagnetic Framework (OOMMF) - OOMMF input parameter files for Tc determination N2 - To simulate the movement of the macroscopic magnetic moment in ferromagnetic systems under the influence of elevated temperatures, the stochastic version of the Landau-Lifshitz (LL) or the Landau-Lifshitz-Gilbert equation with a spin density of one per unit cell has to be used. To apply the stochastic LL to micromagnetic simulations, where the spin density per unit cell is generally higher, a conversion has to be performed. OOMMF sample files MIF) are provided which can be used to determine the Curie temperature for the classical bulk magnets, iron, nickel and cobalt. KW - OOMMF KW - Temperature KW - Micromagnetism KW - Thetaevolve KW - Ferromagnetism KW - Exchange interaction KW - LLG KW - Landau Lifshitz equation KW - Magnetic moment KW - Magnetic nanoparticles KW - Object oriented micromagnetic framework KW - Stochastic Landau Lifshitz Gilbert equation KW - Temperature scaling PY - 2020 DO - https://doi.org/10.26272/opus4-51169 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-51169 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hahn, Marc Benjamin T1 - TOPAS cell model with nanoparticles N2 - These files contain cell models for TOPAS/Geant4 and the inclusion of nano particles in particle scattering simulations. A simple spherical cell with nanoparticles can be generated in a fast manner. The user has the option to include the following organelles: nucleus, mitochondria, cell membrane. Additionally nanoparticles can be included in the cytosol and at the surface of the nucleus and/or the mitochondria. The C++ classes in this repository extend the functionality of the TOPAS (http://www.topasmc.org/) Monte-Carlo program, which is itself a wrapper of the Geant4 MCS Toolkit (http://geant4.org). The sourcecode together with examples and scorers are provided. "If you use this extension please cite the following literature: Hahn, M.B., Zutta Villate, J.M. "Combined cell and nanoparticle models for TOPAS to study radiation dose enhancement in cell organelles." Sci Rep 11, 6721 (2021). https://doi.org/10.1038/s41598-021-85964-2 " KW - Monte-Carlo simulation KW - MCS KW - Geant4 KW - TOPAS KW - TOPAS-nBio KW - Dosimetry KW - Nanoparticles KW - Nanoparticle KW - AuNP KW - Gold KW - Microdosimetry KW - Targeted nanoparticle KW - Simulation KW - Particle scattering KW - Cell KW - Nucleus KW - Mitochondria KW - Cancer therapy KW - Radiation therapy PY - 2020 UR - https://github.com/BAMresearch/TOPAS-CellModels UR - https://github.com/MarcBHahn/TOPAS-CellModels DO - https://doi.org/10.26272/opus4-51150 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-51150 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Kuchenbecker, Petra A1 - Lindemann, Franziska T1 - Final report proficiency test LS BAM-5.4-2024 - Measurement of the particle size distribution of ceramic powders by laser diffraction N2 - This publication is the final report on the proficiency test (PT) LS BAM-5.4-2024 „Measurement of the particle size distribution of ceramic powders by laser diffraction”. The PT was organized by the Federal Institute for Materials Research and Testing (BAM), division 5.4 “Advanced Multi-materials Processing”, Germany. The measurements took place from 2024/05 to 2024/07. The aim of the interlaboratory comparison was the proficiency assessment of the participating laboratories. The PT was performed in accordance with DIN EN ISO/IEC 17043:2010. The harmonized measurement procedure was based on ISO 13320:2020The statistical analysis was performed in accordance with DIN ISO 13528:2020 by use of the software PROLab (QuoData GmbH, Dresden, Germany). A group of 35 laboratories from 14 countries participated in the PT. Laser diffraction analyzers produced by 7 different manufacturers were used. The three test materials were commercial ceramic powders. Overall, the measured characteristic values of the particle size distributions (d10,3, d50,3 and d90,3) were in the size range between 1 and 35 μm. The final report contains all individual results in an anonymous form. KW - Proficiency test KW - Particle size determination KW - Laser diffraction PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610602 DO - https://doi.org/10.26272/opus4-61060 SP - 1 EP - 33 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61060 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - VIDEO A1 - Pauw, Brian Richard T1 - The human factor: A round robin study on the variation in data analyses N2 - This is a remote presentation I gave at the 2022 Small-angle Scattering conference in Campinas, Brazil. The video has been obtained from the conference organisers with their explicit permission for use on YouTube. I've tried to spruce up the audio from the remote recording the best I could. The conference abstract for this talk was: "How much do we, the small-angle scatterers, influence the results of an investigation? What uncertainty do we add by our human diversity in thoughts and approaches, and is this significant compared to the uncertainty from the instrumental measurement factors? After our previous Round Robin on data collection, we know that many laboratories can collect reasonably consistent small-angle scattering data on easy samples. To investigate the next, human component, we compiled four existing datasets from globular (roughly spherical) scatterers, each exhibiting a common complication, and asked the participants to apply their usual methods and toolset to the quantification of the results (https://lookingatnothing.com/index.php/archives/3274). Accompanying the datasets was a modicum of accompanying information to help with the interpretation of the data, similar to what we normally receive from our collaborators. More than 30 participants reported back with volume fractions, mean sizes and size distribution widths of the particle populations in the samples, as well as information on their self-assessed level of experience and years in the field. While the Round Robin is still underway (until the 25th of April, 2022), the initial results already show significant spread in the results. Some of these are due to the variety in interpretation of the meaning of the requested parameters, as well as simple human errors, both of which are easy to correct for. Nevertheless, even after correcting for these differences in understanding, a significant spread remains. This highlights an urgent challenge to our community: how can we better help ourselves and our colleagues obtain more reliable results, how could we take the human factor out of the equation, so to speak? In this talk, we will introduce the four datasets, their origins and challenges. Hot off the press, we will summarize the anonymized, quantified results of the Data Analysis Round Robin. (Incidentally, we will also see if a correlation exists between experience and proximity of the result to the median). Lastly, potential avenues for improving our field will be offered based on the findings, ranging from low-effort yet somehow controversial improvements, to high-effort foundational considerations." T2 - International Small-Angle Scattering Conference (SAS2022) CY - Campinas, Brazil DA - 11.09.2022 KW - Round robin KW - Data analysis KW - X-ray scattering KW - Neutron scattering KW - Nanomaterials KW - Metrology KW - Interlaboratory comparison PY - 2023 UR - https://www.youtube.com/watch?v=t1Rowo--Osg DO - https://doi.org/10.26272/opus4-56897 PB - YouTube, LLC CY - San Bruno, CA, USA AN - OPUS4-56897 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -