TY - CONF A1 - Resch-Genger, Ute T1 - The SMURFnano project - standardized measurements of surface functionalities on nanoparticles N2 - Engineered nanoparticles (NPs) with various chemical compositions and surface functionalities are routinely fabricated for industrial applications such as medical diagnostics, drug delivery, sensing, catalysis, energy conversion and storage, optoelectronics, and information storage. NP function, interaction with biological species, and environmental fate are largely determined by surface functionalities. Reliable, reproducible, and standardized surface characterization methods are therefore vital for quality control of NPs, and mandatory to meet increasing concerns regarding their safety. Also, industry, international standardization organizations, regulatory agencies, and policymakers need validated and standardized measurement methods and reference materials. However, methodologies for determining NP surface properties, including the amount, chemical composition, and homogeneity of surface functionalities and coatings are largely non-standardized. Suitable methods for determining surface functionalities on ligand-stabilized core and core/shell NPs include advanced techniques such as traceable quantitative nuclear magnetic resonance (qNMR) as well as X-ray electron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF-SIMS), and simpler optical and electrochemical methods. The latter less costly methods are often used by SMEs, e.g., for quality control. To validate methods, establish measurement uncertainties, test reference materials, and produce reference data, international interlaboratory comparisons (ILC) on NP surface functionalization measurements are required and well characterized test and reference nanomaterials providing benchmark values.[1] These needs are addressed by the recently started European metrology project SMURFnano involving 12 partners from different National Metrology Institutes, designated institutes, and research institutes, two university groups as well as one large company and one SME producing NPs. This project as well as first results derived from the development of test and reference materials with a well characterized surface chemistry and ongoing interlaboratory comparisons will be presented. T2 - eMRS CY - Strasbourg, France DA - 27.05.2025 KW - Quality assurance KW - Reference analysis KW - Standardization KW - Metrology KW - Reference products KW - Reference materials KW - Mission KW - Surface chemistry KW - Nano KW - Particle KW - qNMR KW - XPS KW - Fluorescence KW - Optical assays KW - Interlaboratory comparison KW - Uncertainty PY - 2025 AN - OPUS4-63243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Brinkmann, A. T1 - A qNMR Method for Quantification of Surface Functional Groups on Silica Nanoparticles: Bilateral Comparisons N2 - Nanomaterials (NM) of different size, shape, morphology, composition, and surface chemistry are used in a wide range of applications, including medical diagnostics, and imaging and consumer products. The importance of an adequate and reliable characterization is crucial for quality control during NM production, for ensuring an optimum function for the desired application, and for risk assessment studies. Currently there is a lack of reliable and validated methods and reference materials for quantifying NM surface functional groups, despite the importance of surface chemistry for the production of colloidally stable materials, further processing steps, and the interaction with the environment and biological species. Following our initial study on the use of qNMR for quantifying the amount of amino groups on surface modified silica (1), we have carried out two bilateral comparisons between NRC and BAM to further develop and optimize a reliable protocol for these measurements (2,3), using aminated silica nanoparticles prepared by multiple methods, both commercial and in-house synthesized, and with varying amine content. Solution qNMR is based on dissolving aminated silica nanoparticles in strong base to release the surface grafted amino silane molecules, followed by the quantification of these molecules by solution qNMR using an internal standard. This method provides the amount of total amino groups present in the sample, which can differ from probe accessible or surface-sensitive measurements performed with X-Ray photoelectron spectroscopy (XPS). Complementary measurements using optical assays, involving a labeling step with a dye reporter, and XPS are employed to assess the probe accessible and surface amine content for representative samples. These measurements, which illustrate the advantages and potential limitations of the different characterization methods, will contribute to establish a basis for testing the protocol in an international inter-laboratory comparison and for standardization at ISO Technical Committee 229 – Nanotechnologies. T2 - BERM CY - Halifax, Canada DA - 01.06.2025 KW - Quality assurance KW - Nano KW - Particle KW - Synthesis KW - Advanced materials KW - Characterization KW - Electron microscopy KW - Silica KW - Surface KW - qNMR KW - Optical assay KW - Interlaboratory comparison KW - Metrology KW - Standardization PY - 2025 AN - OPUS4-63527 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Portesi, C. T1 - qNMR for standardised measurements of surface functionalities on nanoparticles N2 - Engineered nanoparticles have a large application potential in fields such as medicine, sensing, catalysis, energy storage, and opto-electronics [1]. The applicability and performance of engineered nanoparticles is largely determined by their surface chemistry, i.e. functional groups and ligands on the particle surface. However, documented standards to quantify functional groups and ligands currently do not exist. Such standards are required to support quality control of nanomaterial production and surface modification processes, and safe-by-design concepts and to meet regulatory requirements. Here, this issue is addressed by developing and standardizing quantitative Nuclear Magnetic Resonance (qNMR) methods for the characterization of surface functionalized nanoparticles which specifically address the determination of the amount and chemical composition of surface functionalities and coatings. This work is being developed under the EMP project 23NRM02 SMURFnano - Standardised measurements of surface functionalities on nanoparticles. qNMR competence of 7 qNMR laboratories involved in the project was first tested with a molecular model sample i.e. citrate, to be assessed in terms of purity. Citrate is often used as hydrophilic surface ligand for different nanoparticles. Then, the first nanoparticle samples, here a set of aminated SiO2 NPs [1] with a particle size of 100 nm and two amino group densities, prepared and characterized by BAM regarding size and surface charge as well as stability over 21 months with an optical assay and qNMR, were assessed in an international interlaboratory comparison (ILC) on qNMR. Thereby, the amount of surface amino groups introduced by grafting of the silica cores with different amounts of 3-aminopropyl)triethoxysilane (APTES) was quantified by each participant following a sample preparation protocol previously developed by BAM and NRC.The results of the ILC were then used to refine the protocol for sample preparation and to identify critical points for qNMR measurement and data analysis. This work will contribute to the development of a Preliminary Work Item (PWI) 19257 (ISO/TC 229) on surface functional groups and coatings on nano-objects. Also, it will lay the groundwork to perform ILCs on the quantification and determination of the amount of surface functional groups under the roof of VAMAS TWA2 (Surface Chemical Analysis) for different types of nanomaterials possessing industry-relevant surface functionalities using qNMR. These ILCs will be complemented by other techniques like X-Ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). T2 - BERM CY - Halifax, Canada DA - 01.06.2025 KW - Quality assurance KW - Nano KW - Particle KW - Synthesis KW - Advanced materials KW - Characterization KW - Electron microscopy KW - Silica KW - Surface KW - qNMR KW - Optical assay KW - Interlaboratory comparison KW - Metrology KW - Validation KW - Standardization PY - 2025 AN - OPUS4-63443 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bennet, Francesca A1 - Opitz, R. A1 - Ghoreishi, N. A1 - Plate, K. A1 - Barnes, J.-P. A1 - Bellew, A. A1 - Bellu, A. A1 - Ceccone, G. A1 - de Vito, E. A1 - Delcorte, A. A1 - Franquet, A. A1 - Fumageli, F. A1 - Gilliland, D. A1 - Jungnickel, H. A1 - Lee, T.G. A1 - Poleunis, C. A1 - Rading, D. A1 - Shon, H.K. A1 - Spampinato, V. A1 - Son, J.G. A1 - Wang, F. A1 - Wang, Y.-C. A. A1 - Zhao, Y. A1 - Roloff, A. A1 - Tentschert, J. A1 - Radnik, Jörg T1 - VAMAS TWA2 interlaboratory comparison: Surface analysis of TiO2 nanoparticles using ToF-SIMS N2 - Due to the extremely high specific surface area of nanoparticles and corresponding potential for adsorption, the results of surface analysis can be highly dependent on the history of the particles, particularly regarding sample preparation and storage. The sample preparation method has, therefore, the potential to have a significant influence on the results. This report describes an interlaboratory comparison (ILC) with the aim of assessing which sample preparation methods for ToF-SIMS analysis of nanoparticles provided the most intra- and interlaboratory consistency and the least amount of sample contamination. The BAM reference material BAM-P110 (TiO2 nanoparticles with a mean Feret diameter of 19 nm) was used as a sample representing typical nanoparticles. A total of 11 participants returned ToF-SIMS data,in positive and (optionally) negative polarity, using sample preparation methods of “stick-and-go” as well as optionally “drop-dry” and “spin-coat.” The results showed that the largest sources of variation within the entire data set were caused by adventitious hydrocarbon contamination or insufficient sample coverage, with the spin-coating protocol applied in this ILC showing a tendency toward insufficient sample coverage; the sample preparation method or the participant had a lesser influence on results. KW - Secondary Ion Mass Spectrometry KW - VMAAS KW - Titania KW - Interlaboratory comparison KW - Reproducibility PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582290 DO - https://doi.org/10.1116/6.0002814 SN - 0734-2101 VL - 41 IS - 5 SP - 053210-1 EP - 053210-13 PB - AIP (American Institute of Physics) AN - OPUS4-58229 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Micro and Nano Plastics in the Environment N2 - The VAMAS/TWA 45 Project 2 “Development of standardized methodologies for characterisation of microplastics with microscopy and spectroscopy methods” involving 85 participants around the world is primarily discussed with respect to the results received and a first data evaluation. Status of the Project "Guidelines for defining reference materials for plastic degradation in marine environment" is reported and two new project proposals are presented: "Development of standardized methodologies for characterisation of nanoplastics (starting soon, BAM as leader?) and "Development of analytical protocols for the identification and quantification of microplastics of fibrous shape (still in negotiation)". T2 - Versailles Project on Advanced Materials and Standards (VAMAS) 48th Steering Committee Meeting CY - New Delhi, India DA - 09.10.2023 KW - Microplastics KW - Nanoplastics KW - Interlaboratory comparison KW - VAMAS KW - Reference materials KW - ISO PY - 2023 UR - https://www.nplindia.org/index.php/amcsnzt_2023/ AN - OPUS4-58539 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ciornii, Dmitri A1 - Hodoroaba, Vasile-Dan A1 - Wachtendorf, Volker A1 - Fengler, Petra A1 - Altmann, Korinna T1 - Interlaboratory Comparison Reveals State of the Art in Microplastic Detection and Quantification Methods N2 - In this study, we investigate the current accuracy of widely used microplastic (MP) detection methods through an interlaboratory comparison (ILC) involving ISO-approved techniques. The ILC was organized under the prestandardization platform of VAMAS (Versailles Project on Advanced Materials and Standards) and gathered a large number (84) of analytical laboratories across the globe. The aim of this ILC was (i) to test and to compare two thermo-analytical and three spectroscopical methods with respect to their suitability to identify and quantify microplastics in a water-soluble matrix and (ii) to test the suitability of the microplastic test materials to be used in ILCs. Two reference materials (RMs), polyethylene terephthalate (PET) and polyethylene (PE) as powders with rough size ranges between 10 and 200 μm, were used to press tablets for the ILC. The following parameters had to be assessed: polymer identity, mass fraction, particle number concentration, and particle size distribution. The reproducibility, SR, in thermo-analytical experiments ranged from 62%−117% (for PE) and 45.9%−62% (for PET). In spectroscopical experiments, the SR varied between 121% and 129% (for PE) and 64% and 70% (for PET). Tablet dissolution turned out to be a very challenging step and should be optimized. Based on the knowledge gained, development of guidance for improved tablet filtration is in progress. Further, in this study, we discuss the main sources of uncertainties that need to be considered and minimized for preparation of standardized protocols for future measurements with higher accuracy. KW - Microplastics KW - Interlaboratory comparison KW - PlasticsFatE KW - PET KW - PE KW - Reference materials KW - VAMAS KW - Thermo-analytical methods KW - Spectroscopical methods PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630462 DO - https://doi.org/10.1021/acs.analchem.4c05403 SN - 1520-6882 VL - 97 SP - 8719 EP - 8728 PB - ACS Publications AN - OPUS4-63046 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ciornii, Dmitri T1 - Getting reliable data on microplastic detection methods by means of ILC N2 - There is an urgent demand for reliable data on microplastic analysis, particularly on its physico-chemical properties as well as validated methodology to obtain such data. Through interlaboratory comparisons (ILCs) it becomes possible to assess accuracy and precision of methods by involving many laboratories around the world. At BAM, my tasks focused around organisation of an ILC on physico-chemical characterisation of microplastic detection methods under the international pre-standardisation platform VAMAS (www.vamas.org/twa45/) as Project 2 “Development of standardized methodologies for characterisation of microplastics with microscopy and spectroscopy methods” under the Technical Working Area TWA 45 “Micro and Nano Plastics in the Environment”. With a proud number of 84 participants this ILC is able to provide superior statistical results. Thermoanalytical (Py-GC/MS and TED-GC/MS) and vibrational (µ-IR and µ-Raman) methods were asked for identification and quantification of microplastic test samples according to mass or particle number. Preliminary results indicate which methods show a higher accuracy and precision and reveal some sample preparation ideas which work best for microplastics characterisation. At the end of the ILC an overall plausibility of the results will be assessed. T2 - CUSP Early Career Researchers Meeting CY - Online meeting DA - 21.11.2023 KW - Micro- and Nanoplastics KW - Interlaboratory comparison KW - Microplastic reference materials PY - 2023 AN - OPUS4-59056 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -