TY - JOUR A1 - Hülagü, Deniz A1 - Tobias, Charlie A1 - Climent Terol, Estela A1 - Gojani, Ardian A1 - Rurack, Knut A1 - Hodoroaba, Vasile-Dan T1 - Generalized Analysis Approach of the Profile Roughness by Electron Microscopy with the Example of Hierarchically Grown Polystyrene–Iron Oxide–Silica Core–Shell–Shell Particles N2 - The roughness as a property of core–shell (CS) microparticles plays a key role in their functionality. Quantitative evaluation of the roughness of CS microparticles is, however, a challenging task with approaches using electron microscopy images being scarce and showing pronounced differences in terms of methodology and results. This work presents a generalized method for the reliable roughness determination of nonplanar specimens such as CS particles from electron microscopic images, the method being robust and reproducible with a high accuracy. It involves a self-written software package (Python) that analyzes the recorded images, extracts corresponding data, and calculates the roughness based on the deviation of the identified contour. Images of single particles are taken by a dual mode scanning electron microscopy (SEM) setup which permits imaging of the same field-of-view of the sample with high resolution and surface sensitive in SE InLens mode as well as in transmission mode (TSEM). Herein, a new type of polystyrene core–iron oxide shell–silica shell particles is developed to serve as a set of lower micrometer-sized study objects with different surface roughness; the analysis of their images by the semiautomatic workflow is demonstrating that the particles’ profile roughness can be quantitatively obtained. KW - Core–shell particles KW - Image analysis KW - Nanoparticles KW - Roughness KW - SEM KW - transmission mode PY - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-542576 SP - 1 EP - 9 PB - Wiley-VCH AN - OPUS4-54257 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Menzel, Friederike A1 - Menzel, Friederike A1 - Conradi, Bianca A1 - Rodenacker, K. A1 - Gorbushina, Anna A1 - Schwibbert, Karin T1 - Semi-automated statistical quantification of initial colonization of bacteria on different materials under standardized conditions N2 - The formation of biofilms on different materials provokes high costs in industrial processes, as well as in medical applications. Therefore, the interest in development of new materials with improved surfaces to reduce bacterial colonization rises. In order to evaluate the quality and safety of these new materials, it is highly important to ensure world-wide comparable tests that are relying on statistical evidence. The only way to reach this statistical safety is through a high-throughput Screening under standardized test conditions. We developed a flow through system for cultivation of biofilm-forming bacteria under controlled conditions with a total capacity for testing up to 32 samples in parallel. Quantification of the surface colonization was done by staining the bacterial cells with a fluorescence marker, followed by epifluorescence microscopy. More than 100 images of each sample were automatically taken and the surface coverage was estimated with the free open source software gmic (http://gmic.eu), followed by a precise statistical evaluation. Overview images of all gathered pictures of the whole material coupon were generated to illuminate the colonization characteristics of the selected bacteria on certain materials. With this method, differences in bacterial colonization on different materials can be quantified in a statistically validated manner. The innovative and solid test procedure will support the design of improved materials for medical and industrial applications such as implants, ship hulls, pipelines, heat exchangers, aquaculture equipments, photovoltaic-panels and fundaments of wind power plants. T2 - Vereinigung für Allgemeine und Angewandte Mikrobiologie - Jahrestagung 2016 CY - Jena, Germany DA - 13.03.2016 KW - Biofilm cultivation KW - Image analysis KW - Microscopy PY - 2016 AN - OPUS4-37724 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mast, J. A1 - Verleysen, E. A1 - Hodoroaba, Vasile-Dan A1 - Kaegi, R. ED - Hodoroaba, Vasile-Dan ED - Unger, Wolfgang ED - Shard, A. G. T1 - Characterization of nanomaterials by transmission electron microscopy - Measurement procedures N2 - In this chapter, approaches are proposed for the descriptive and quantitative characterization of nano-objects with nanometer resolution. Measurements are based on the analysis of the characteristics of 2D projections of individual particles visualized on transmission electron micrographs. Incorporation of spectroscopic methods (EDS and EELS) for elemental analysis of nano-objects is recommended to identify subpopulations of nano-objects in mixtures based on their chemical composition. The focus lies on the determination of physicochemical properties which are essential in a legislatory and regulatory context to define the material as a nanomaterial (NM), and to assess its safety and toxicological potential, using widely accessible equipment. KW - Nanoparticles KW - Sample preparation KW - Image analysis KW - Transmission electron microscopy PY - 2020 SN - 978-0-12-814182-3 U6 - https://doi.org/10.1016/B978-0-12-814182-3.00004-3 SP - 29 EP - 48 PB - Elsevier CY - Amsterdam AN - OPUS4-50121 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bennet, Francesca A1 - Burr, L. A1 - Schmid, D. A1 - Hodoroaba, Vasile-Dan T1 - Towards a method for quantitative evaluation of nanoparticles in suspension via Microprinting and SEM analysis N2 - A series of different nanoparticle suspensions (Gold, Latex, and SiO2 in varying concentrations) were microprinted onto TEM grids in a 4 x 4 array in the concentration range 7x10^8 to 1x10^11 NP/mL and imaged with SEM and TSEM. Concentrations and printing conditions (temperature, relative humidity) were varied in order to minimize the coffee ring effect. T2 - nanoSAFE 2020 CY - Online meeting DA - 16.11.2020 KW - Nanoparticles KW - Microprinting KW - Image analysis PY - 2020 AN - OPUS4-51699 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chemello, Giovanni A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan T1 - Measurement of the morphology of graphene related 2D materials as flakes N2 - The presentation shows the results of the mini-interlaboratory comparison focused on the measurement of the morphology of graphene oxide flakes using scanning electron microscopy. In this work, a route for the sample preparation, SEM measurement and image analysis is proposed. The results of the image analysis, performed on 200+ flakes per sample, are presented by comparing the distributions of the size and shape descriptors calculated according to two different approaches. The influences of a different SEM measurement operator, analysis approach and analysis operator on the final size and shape distributions are highlighted. T2 - EMRS Fall 2023 CY - Warsaw, Poland DA - 18.09.2023 KW - Graphene oxide KW - SEM KW - 2D flakes KW - Image analysis PY - 2023 AN - OPUS4-58752 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -