TY - JOUR A1 - Mrkwitschka, Paul A1 - Mühlbauer, Michaela A1 - Rossi, Andrea A1 - Pellegrino, Francesco A1 - Zurutuza, Amaia A1 - Radnik, Jörg A1 - Meier, Florian A1 - Hodoroaba, Vasile-Dan T1 - Morphological Analysis of Graphene Oxide by Scanning Electron Microscopy and Correlative Field-flow Fractionation Coupled with Multi-angle Light Scattering N2 - In this paper graphene related 2D materials (GR2M) arre investigated by centrifugal field flow fractioning (CF3) and SEM. Three materials were selected as case studies (CS): graphene „HD-G (CS I), graphene oxide UniTo“ (CS II), and graphene oxide „Graphenea“ (CS III). For CS I particles were evaluated as constituent particles in agglomerates, for the other two materials only isolated (non aggregated/agglomerated) flakes were considered for determination of the area equivalent circular diameter (ECD). Size analysis of all three materials was carried out by CF3 coupled with MALS (Multi-Angle Light Scattering). For evaluation, it was found that the data obtained was best suited to a disc model. Results are in good agreement when compared to the sizes obtained before CF3 analysis. CS II material is too heterogenous to accurately determine flake size by imaging. CF3 coupled with MALS enables to assess fractions within the highly heterogenous material of CS II. Imaging of the material in CS III after CF3 measurement indicates that the procedure is non-destructive. This could not be verified for the CS‘s I & II As a next step we plan to analyse the fractionated samples by imaging them within a SEM wet-cell. KW - 2D Materials KW - SEM KW - Centrifugal field flow fractionation (CF3) KW - Imaging KW - Size distribution PY - 2025 DO - https://doi.org/10.1093/mam/ozaf048.222 VL - 31 IS - 7 SP - 442 EP - 443 PB - Oxford Academic AN - OPUS4-63804 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - You, Zengchao A1 - Meier, Florian A1 - Weidner, Steffen ED - Weidner, Steffen T1 - Comparison of miniaturized and conventional asymmetrical flow field flow fractionation (AF4) channels for nanoparticle separation N2 - The performance of a miniaturized channel for the separation of polymer and metal nanoparticles (NP) using Asymmetrical Flow Field-Flow Fractionation (AF4) was investigated and compared with a conventional AF4 system. To develop standard separation methods, experimental parameters like cross flow, gradient profile and injection time were varied and optimized. Corresponding chromatographic parameters were calculated and compared. Our results indicate that the chromatographic resolution in the miniaturized channel is lower, whereas significantly shorter analyses time and less solvent consumption were obtained. Moreover, the limit of detection (LOD) and limit of quantification (LOQ) obtained from hyphenation with a UV-detector are obviously lower than in a conventional channel, which makes the miniaturized channel interesting for trace analysis. KW - Nanoparticles separation asymetrical flow field flow fractionation PY - 2017 DO - https://doi.org/10.3390/separations4010008 SN - 2297-8739 VL - 4 IS - 1 SP - 8, 1 EP - 11 AN - OPUS4-47196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bartczak, Dorota A1 - Sikora, Aneta A1 - Goenaga-Infante, Heidi A1 - Altmann, Korinna A1 - Drexel, Roland A1 - Meier, Florian A1 - Alasonati, Enrica A1 - Lelong, Marc A1 - Cado, Florence A1 - Chivas-Joly, Carine A1 - Fadda, Marta A1 - Sacco, Alessio A1 - Rossi, Andrea Mario A1 - Pröfrock, Daniel A1 - Wippermann, Dominik A1 - Barbero, Francesco A1 - Fenoglio, Ivana A1 - Booth, Andy M. A1 - Sørensen, Lisbet A1 - Igartua, Amaia A1 - Wouters, Charlotte A1 - Mast, Jan A1 - Barbaresi, Marta A1 - Rossi, Francesca A1 - Piergiovanni, Maurizio A1 - Mattarozzi, Monica A1 - Careri, Maria A1 - Caebergs, Thierry A1 - Piette, Anne-Sophie A1 - Parot, Jeremie A1 - Giovannozzi, Andrea Mario T1 - Multiparameter characterisation of a nano-polypropylene representative test material with fractionation, light scattering, high-resolution microscopy, spectroscopy, and spectrometry methods N2 - Reference and quality control materials with comparable physicochemical properties to nanoplastic contaminants present in environmental and food nanoplastics are currently lacking. Here we report a nanoplastic polypropylene material prepared using a top-down approach involving mechanical fragmentation of larger plastics. The material was found to be homogeneous and stable in suspension and has been characterised for average particle size, size distribution range, particle number concentration, polypropylene mass fraction and inorganic impurity Content using a wide range of analytical methods, including AF4, cFFF, PTA, (MA)DLS, MALS, SEM, AFM, TEM, STEM, EDS,Raman, ICP-MS and pyGC-MS. The material was found to have a broad size distribution, ranging from 50 nm to over 200 nm, with the average particle size value dependent on the technique used to determine it. Particle number concentration ranged from 1.7–2.4 × 1010 g−1 , according to PTA. Spectroscopy techniques confirmed that the material was polypropylene, with evidence of aging due to an increased level of oxidation. The measured mass fraction was found to depend on the marker used and ranged between 3 and 5 μg g−1 . Inorganic impurities such as Si, Al, Mg, K, Na, S, Fe, Cl and Ca were also identified at ng g−1 levels. Comparability and complementarity across the measurement methods and techniques is also discussed. KW - Polypropylene KW - Nanoplastics KW - Analytics KW - Reference material KW - Scattering methods PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654680 DO - https://doi.org/10.1039/D5EN00917K SN - 2051-8153 SP - 1 EP - 15 PB - Royal Society of Chemistry (RSC) AN - OPUS4-65468 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -