TY - RPRT A1 - Hodoroaba, Vasile-Dan A1 - Mielke, Johannes T1 - Techniques evaluation report for selection of characterisation methods N2 - This report is the result of a comprehensive study on the available CMs which come potentially in question for the reliable analysis of the number based size distribution of a nanomaterial according to the EC recommendation for a definition of nanomaterial. Based on the performance criteria already established in NanoDefine the potential CMs are evaluated according to studies available in the literature as well as following the expertise of the NanoDefine consortium partners. The specific advantages and disadvantages of each method with respect to its applicability to the scope of NanoDefine are particularly highlighted. An CM evaluation table is produced so that the mostly suited CMs with respect to the EC definition can be grouped and recommended to the corresponding NanoDefine work packages for further specific development (improvement and adaption), or for direct validation and standardisation, respectively. The actual evaluation report including the recommended CMs will be revised and, if necessary, eventually updated at the mid time of the project. The update will be jointly discussed in the NanoDefine consortium on the basis of the results of testing the methods on the NanoDefine real world materials. KW - Nanomaterial KW - Characterization method KW - EC definition PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-389473 UR - http://www.nanodefine.eu/publications/reports/NanoDefine_TechnicalReport_D3.1.pdf SP - D3.1, 1 EP - 57 CY - Wageningen, The Netherlands AN - OPUS4-38947 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, P. A1 - Mielke, Johannes A1 - Hodoroaba, Vasile-Dan A1 - Kägi, R. A1 - Ryner, M. T1 - Assessment of different electron microscopy techniques for particle size quantification of potential nanomaterials N2 - While nano-scaled intermediate and consumer products are omnipresent in many industries, one challenge consists in the development of methods that reliably identify, characterize and quantify nanomaterials both as a substance and in various matrices. For product registration purposes, the European Commission proposed a definition for nanomaterial which requires a quantitative size determination of the primary particles in a sample down to sizes of 1 nm. According to a material is defined as nano if 50% of the primary particles are observed to comprise a smallest dimension <100 nm. The NanoDefine project was set up to develop and validate a robust, readily implementable and cost-effective measurement approach to obtain a quantitative particle size distribution and to distinguish between nano and non-nano materials according to the definition Among the available particle sizing techniques, electron microscopy was found to be one option meeting most of the requirements of the regulation. However, the use of electron microscopy for particle sizing is often limited by cost per sample, availability in industry, particle agglomeration/aggregation, extremely broad size distributions, 2D materials and operator bias in case of manual evaluation. PY - 2015 DO - https://doi.org/10.1017/S1431927615012799 SN - 1431-9276 SN - 1435-8115 VL - 21 IS - Suppl. 3 SP - Paper 1200, 2403 EP - 2404 PB - Cambridge University Press CY - New York, NY AN - OPUS4-34922 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mielke, Johannes A1 - Dohányosová, P. A1 - Müller, P. A1 - López-Vidal, S. A1 - Hodoroaba, Vasile-Dan T1 - Evaluation of electrospray as a sample preparation tool for electron microscopic investigations: Toward quantitative evaluation of nanoparticles N2 - The potential of electrospray deposition, for the controlled preparation of particles for imaging in electron microscopes, is evaluated on various materials: from mono-modal suspensions of spherical particles to multimodal suspensions and to real-world industrial materials. It is shown that agglomeration is reduced substantially on the sample carrier, compared with conventional sample preparation techniques. For the first time, it is possible to assess the number concentration of a tri-modal polystyrene suspension by electron microscopy, due to the high Deposition efficiency of the electrospray. We discovered that some suspension stabilizing surfactants form artifact particles during electrospraying. These can be avoided by optimizing the sprayed suspension. KW - Electrospary KW - Nanoparticles KW - Sample preparation KW - TEM grid KW - SEM PY - 2017 DO - https://doi.org/10.1017/S1431927616012587 SN - 1431-9276 SN - 1435-8115 VL - 23 IS - 1 SP - 163 EP - 172 PB - Cambridge University Press AN - OPUS4-39244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Cios, G. A1 - Tokarski, T. A1 - Mansfeld, Ulrich A1 - Ortel, Erik A1 - Mielke, Johannes A1 - Pellegrino, F. A1 - Maurino, V. T1 - Towards 3D Understanding of Non-spherical Nanoparticles by Transmission Kikuchi Diffraction (TKD) for Improved Particle Size Distribution by Electron Microscopy N2 - In this paper one refined approach is applied to determine the exact orientation of bipyramidal TiO2 nanoparticles prepared with good dispersion as almost isolated particles on a carbon TEM grid. The advantages of the recently developed high-throughput Transmission Kikuchi Diffraction (TKD) are used to identify quickly and reliably the geometrical orientation of the crystalline TiO2 nanoparticle bipyramids (anatase) on a statistically relevant number of particles. KW - Nanoparticles KW - Transmission Kikuchi Diffraction (TKD) KW - Electron microscopy KW - TiO2 KW - 3D PY - 2020 DO - https://doi.org/10.1017/S1431927620013999 VL - 26 IS - S2 SP - 260 EP - 261 PB - Cambridge University Press CY - Cambridge, UK AN - OPUS4-51772 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sarma, Dominik A1 - Mielke, Johannes A1 - Sahre, Mario A1 - Beck, Uwe A1 - Hodoroaba, Vasile-Dan A1 - Rurack, Knut T1 - TSEM-based contour analysis as a tool for the quantification of the profile roughness of silica shells on polystyrene core particles N2 - Core-shell (CS) particles with a polymeric core and a silica shell play an important role in the materials and (bio)analytical sciences. Besides the establishment of reliable synthesis procedures, comprehensive particle characterization is essential for batch-to-batch reproducibility and objective performance assessment across architectures, protocols, and laboratories. Particle characterization with respect to size, size distribution, shell thickness and texture, surface area and roughness or materials composition is commonly conducted with different analytical methods, often on different samples. Our approach uses a dual-mode TSEM/SEM set-up with an EDX detector to obtain a complementary data set with sufficient statistical confidence of one and the same sample on a single instrument. Our protocol reveals information about size, size distribution and shell thickness of the various particles employed from overview images, while an increased field of view (FOV) and high-resolution EDX analysis yields detailed information on shell texture and elemental composition. An image analysis tool was developed to derive and quantify the profile roughness of CS particles from individual beads. Comparison with surface roughness data from AFM showed a similar trend in roughness across the series of particles. Reliable classification into smooth and rough is proposed and roughness changes within different particle batches were tracked systematically. KW - Core-shell particles KW - Electron microscopy KW - Transmission mode KW - Roughness KW - Image analysis PY - 2017 DO - https://doi.org/10.1016/j.apsusc.2017.07.099 SN - 0169-4332 SN - 1873-5584 VL - 426 IS - 1 SP - 446 EP - 455 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-42256 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mielke, Johannes T1 - Evaluation and selection of techniques and methodologies to support the implementation of the EC recommendation for a definition of nanomaterial T2 - Synergy Workshop NanoDefine with other NSC (Nano Safety Cluster) Projects CY - Copenhagen, Denmark DA - 2014-06-06 PY - 2014 AN - OPUS4-30958 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mielke, Johannes T1 - Evaluierung der Messmethoden zur Implementierung der EU-Empfehlung zur Definition von Nanomaterialien im Projekt "NanoDefine" T2 - Workshop von Bundesbehörden/VCI/VdMi "Messstrategien und Messmethoden für Nanomaterialien" CY - Berlin, Germany DA - 2015-09-08 PY - 2015 AN - OPUS4-34064 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Salge, T. A1 - Mielke, Johannes A1 - Ortel, Erik A1 - Schmidt, R. T1 - Characterisation of nanoparticles by means of high-resolution SEM/EDS in transmission mode N2 - Advances in scanning electron microscopy (SEM) enable the high-resolution imaging of single nanoparticles (NPs) with sizes well below 10 nm. The SEM analysis in transmission mode (T-SEM) of NPs on thin film supports has many benefits when compared to the analysis of NPs on bulk substrates. The enhanced material (mass – thickness) contrast of the T-SEM imaging mode is well suited for in-depth and, particularly valuable, to very accurate, traceable, lateral dimensional measurements of NPs. Compared to samples prepared on bulk substrates, T-SEM with energy dispersive X-ray spectroscopy (EDS) achieves a drastically improved spatial resolution of the emitted X-rays. The poor signal-to-noise ratio of the X-ray spectra emitted by a single nanoparticle (NP) can be improved by the use of high-sensitivity (high collection solid angle) silicon drift (SDD), energy-dispersive X-ray spectrometers (EDS). The EDS spectral imaging of a single NP with a spatial resolution below 10 nm has become possible. This is demonstrated by means of various examples of nanostructures. Advanced data processing of T-SEM/EDS results sets the stage for the automated classification of NPs by feature analysis. This method combines the detection of morphological structures of interest by image processing of T-SEM micrographs with the chemical classification by EDS. T2 - European Microbeam Analysis Society’s 14th European Workshop on Modern Developments and Applications in Microbeam Analysis (EMAS 2015) CY - Portorož, Slovenia DA - 03.05.2015 KW - High-resolution KW - SEM KW - T-SEM KW - EDX KW - Nanoparticles PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-355628 UR - http://iopscience.iop.org/article/10.1088/1757-899X/109/1/012006 DO - https://doi.org/10.1088/1757-899X/109/1/012006 SN - 1757-899X VL - 109 SP - 012006-1 EP - 012006-12 PB - IOP Publishing Ltd CY - Bristol, UK AN - OPUS4-35562 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Rauscher, H. A1 - Mech, A. A1 - Gaillard, C. A1 - Stintz, M. A1 - Wohlleben, W. A1 - Weigel, St. A1 - Ghanem, A. A1 - Hodoroaba, Vasile-Dan A1 - Babick, F. A1 - Mielke, Johannes T1 - Recommendations on a revision of the EC definition of nanomaterial based on analytical possibilities; updated N2 - In October 2011 the European Commission (EC) published a "Recommendation on the definition of na-nomaterial" (2011/696/EU), to promote consistency in the interpretation of the term "nanomaterial" for legislative and policy purposes in the EU. The EC NM Definition includes a commitment to its review in the light of experience and of scientific and technological developments. This review is ongoing in 2017 and as a contribution to the review the Joint Research Centre of the European Commission (JRC) has already developed a series of three scientific-technical reports with the title: “Towards a review of the EC Recommendation for a definition of the term nanomaterial” which provides to the EC policy services sci-ence-based options on how the definition could be revised or supported with additional guidance. The overarching nature and wide scope of the EC NM Definition, as it does not exclude a priori any particulate material regardless the state, form and size, creates many analytical challenges in its imple-mentation for all stakeholders, including enterprises and regulators. The NanoDefine project has as core objective to support the implementation of the EC NM Definition. In an earlier report1 key aspects of the EC NM Definition were addressed, with the goal to improve the implementability of the EC NM Definition. Based on further developments and results obtained in NanoDefine project that first report was updated and is presented here. The key aspects are discussed based on the results of four years of research performed within the framework of the project. As a result this report assesses how well the requirements of the EC NM Definition can be fulfilled with currently available analytical possibilities. It presents recommendations and options on a revision of the EC NM Definition to improve the implementability of the definition based on currently available analytical possi-bilities, according to the state of the art in 2017. Of the technical issues considered in this report, the following seem to deserve the most attention in terms of clarification of the definition and/or provision of additional implementation guidance: 'external dimension', ‘number based particle size distribution‘, ‘polydispersity‘ and ‘upper size limit‘, the term ‘particle’, the ‘means to prove that a material is not a nanomaterial‘ and ‘the role of the volume specific sur-face area (VSSA)‘, and "particulate materials'. KW - EU definition of a nanomaterial KW - Nanoparticles KW - Revision KW - Update 2017 PY - 2017 UR - http://www.nanodefine.eu/index.php/nanodefine-publications/nanodefine-technical-reports SP - D7.10, 1 EP - D7.10, 71 PB - The NanoDefine Consortium CY - Wageningen, The Netherlands AN - OPUS4-43540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Babick, F. A1 - Mielke, Johannes A1 - Wohlleben, W. A1 - Weigel, St. A1 - Hodoroaba, Vasile-Dan T1 - How reliably can a material be classified as a nanomaterial? Available particle-sizing techniques at work N2 - Currently established and projected regulatory frameworks require the classification of materials (whether nano or non-nano) as specified by respective definitions, most of which are based on the size of the constituent particles. This brings up the question if currently available techniques for particle size determination are capable of reliably classifying materials that potentially fall under these definitions. In this study, a wide variety of characterisation techniques, including counting, fractionating, and spectroscopic techniques, has been applied to the same set of materials under harmonised conditions. The selected materials comprised well-defined Quality control materials (spherical, monodisperse) as well as industrial materials of complex shapes and considerable polydispersity. As a result, each technique could be evaluated with respect to the determination of the number-weighted median size. Recommendations on the most appropriate and efficient use of techniques for different types of material are given. KW - Nanomaterial classification KW - Nanoparticle KW - Number-weighted median size KW - Tiered KW - Particle size analysis KW - Nanometrology KW - Characterisation techniques PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-367922 UR - http://link.springer.com/article/10.1007/s11051-016-3461-7 DO - https://doi.org/10.1007/s11051-016-3461-7 SN - 1388-0764 SN - 1572-896X VL - 18 IS - 6 SP - Article 158, 1 EP - 40 PB - Springer AN - OPUS4-36792 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Salge, T. A1 - Mielke, Johannes A1 - Ortel, Erik A1 - Schmidt, R. T1 - Characterisation of nanoparticles by means of high-resolution SEM/EDS N2 - Advances in scanning electron microscopy (SEM) enable the high-resolution imaging of single nanoparticles (NPs) with sizes well below 10 nm. The SEM analysis in transmission mode (T-SEM) of NPs on thin film supports has many benefits when compared to the analysis of NPs on bulk substrates. The enhanced material (mass - thickness) contrast of the T-SEM imaging mode is well suited for in-depth and, particularly valuable, to very accurate, traceable, lateral dimensional measurements of NPs. Compared to samples prepared on bulk substrates, T-SEM with energy dispersive X-ray spectroscopy (EDS) achieves a drastically improved spatial resolution of the emitted X-rays. The poor signal-to-noise ratio of the X-ray spectra emitted by a single nanoparticle (NP) can be improved by the use of high-sensitivity (high collection solid angle) silicon drift (SDD), energy-dispersive X-ray spectrometers (EDS). The EDS spectral imaging of a single NP with a spatial resolution below 10 nm has become possible. This is demonstrated by means of various examples of nanostructures. Advanced data processing of T-SEM/EDS results sets the stage for the automated classification of NPs by feature analysis. This method combines the detection of morphological structures of interest by image processing of T-SEM micrographs with the chemical classification by EDS. T2 - EMAS 2015 - 14th European workshop on modern developments and applications in microbeam analysis CY - Portoroz, Slovenia DA - 03.05.2015 KW - SEM KW - T-SEM KW - EDX KW - Nanoparticles KW - High-resolution PY - 2015 SN - 978-90-8227-691-6 DO - https://doi.org/10.1088/1757-899X/109/1/012006 SP - NUR code:972 - Materials Science, 187-199 AN - OPUS4-33258 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Rauscher, H. A1 - Mech, A. A1 - Gaillard, C. A1 - Stintz, M. A1 - Wohlleben, W. A1 - Weigel, St. A1 - Ghanem, A. A1 - Hodoroaba, Vasile-Dan A1 - Babick, F. A1 - Mielke, Johannes T1 - Recommendations on a Revision of the EC Definition of Nanomaterial Based on Analytical Possibilities N2 - In October 2011 the European Commission (EC) published a "Recommendation on the definition of nanomaterial" (2011/696/EU), to promote consistency in the interpretation of the term "nanomaterial" for legislative and policy purposes in the EU. The EC NM Definition includes a commitment to its review in the light of experience and of scientific and technological developments. This review is ongoing in 2015 and as a contribution to the review the Joint Research Centre of the European Commission (JRC) has already developed a series of three scientific-technical reports with the title: “Towards a review of the EC Recommendation for a definition of the term nanomaterial” which provides to the EC policy services science-based options on how the definition could be revised or supported with additional guidance. The overarching nature and wide scope of the EC NM Definition, as it does not exclude a priori any particulate material regardless the state, form and size, creates many analytical challenges in its imple-mentation for all stakeholders, including enterprises and regulators. The NanoDefine project has as core objective to support the implementation of the EC NM Definition. In this report key aspects of the EC NM Definition are addressed, with the goal to improve the implement-ability of the EC NM Definition. These aspects are presented and discussed based on the results of two years of research performed within the framework of the project. As a result this report assesses how well the requirements of the EC NM Definition can be fulfilled with currently available analytical possi-bilities. It presents recommendations and options on a revision of the EC NM Definition to improve the implementability of the definition based on currently available analytical possibilities, according to the state of the art of mid-2015. Of the technical issues considered in this report, the following seem to deserve the most attention in terms of clarification of the definition and/or provision of additional implementation guidance:  The term ‘external dimension’. A clear definition of 'External dimension' should be included in the text of the EC NM definition and more precise guidance on what is considered as an external dimension and how to properly character-ise it should be provided.  The ‘number based particle size distribution‘. The EC NM Definition uses a threshold related to the number based size distribution of particles. Yet most of the easily available techniques provide a mass-, volume- or scattered light intensity-based size distribution which needs to be converted into a number based distribution to be used for regulatory pur-poses. A specific guidance on the conditions under which these methods can be used to identify a na-nomaterial by employing appropriate quantity or metrics conversion should be provided.  The ‘polydispersity‘ and ‘upper size limit‘ Polydispersity is a challenge for the measurement of particle size distribution for the EC NM definition, specifically for materials with high polydispersity index and broad size distribution especially when the volume or mass of the fraction containing particles below 100 nm is very small. Therefore a dedicated guidance should be provided that allows applying an upper size limit in measurements and particle statistics. KW - Nanomaterial KW - EU Definition of nanomaterial KW - Nanoparticles PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-432339 UR - http://www.nanodefine.eu/publications/reports/NanoDefine_TechnicalReport_D7.10.pdf SP - 1 EP - 68 PB - The NanoDefine Consortium CY - Wageningen, The Netherlands AN - OPUS4-43233 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pellegrino, Francesco A1 - Ortel, Erik A1 - Mielke, Johannes A1 - Schmidt, R. A1 - Maurino, V. A1 - Hodoroaba, Vasile-Dan T1 - Customizing New Titanium Dioxide Nanoparticles with Controlled Particle Size and Shape Distribution: A Feasibility Study Toward Reference Materials for Quality Assurance of Nonspherical Nanoparticle Characterization N2 - An overview is given on the synthesis of TiO2 nanoparticles with well-defined nonspherical shapes (platelet like, bipyramidal, and elongated), with the focus on controlled, reproducible synthesis, as a key requirement for the production of reference materials with homogeneous and stable properties. Particularly with regard to the nanoparticle shapes, there is a high need of certified materials, solely one material of this type being commercially available since a few months (elongated TiO2). Further, measurement approaches with electron microscopy as the golden method to tackle the nanoparticle shape are developed to determine accurately the size and shape distribution for such nonspherical particles. A prerequisite for accurate and easy (i.e., automated) image analysis is the sample preparation, which ideally must ensure a deposition of the nanoparticles from liquid suspension onto a substrate such that the particles do not overlap, are solvent-free, and have a high deposition density. Challenges in the Synthesis of perfectly monodispersed and solvent-free TiO2 nanoparticles of platelet and acicular shapes are highlighted as well as successful measurement approaches on how to extract from 2D projection electron micrographs the most accurate spatial information, that is, true 3D size, for example, of the bipyramidal nanoparticles with different geometrical orientations on a substrate. KW - Nanoparticles KW - Titanium dioxide KW - Reference materials KW - Standardisation KW - Particle size and shape distribution PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538849 DO - https://doi.org/10.1002/adem.202101347 VL - 24 IS - 6 SP - 1 EP - 10 PB - Wiley-VCH AN - OPUS4-53884 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -