TY - GEN A1 - Bresch, Harald A1 - Schmidt, Alexandra A1 - Kämpf, K. A1 - Bachmann, V. A1 - Peters, T. A1 - Kuhlbusch, T. T1 - Test Guideline No. 125 - Nanomaterial Particle Size and Size Distribution of Nanomaterials N2 - The OECD Working Party on Manufactured Nanomaterials (WPMN) has actively worked towards understanding possible safety issues for manufactured nanomaterials and has contributed significantly to resolving these by developing Test Guidelines, Guidance Documents, Test Reports and other publications with the aim of a safe use of manufactured nanomaterials. To address the specific needs of manufactured nanomaterials, the OECD Test Guideline No. 110 “Particle Size Distribution/Fibre Length and Diameter Distributions” was identified as one of the test guidelines (TGs) to require an update. The current TG 110 (adopted in 1981) is only valid for particles and fibres with sizes above 250 nm. The WPMN prioritised to either update TG 110 to be applicable also to particles at the nanoscale or draft a new nanomaterial specific (TG). Eventually, it was decided to develop a new TG that covers the size range from 1 nm to 1000 nm, intended for particle size and particle size distribution measurements of nanomaterials. Paragraph 11 provides further justification on the need for such measurements for nanomaterials. This TG overlaps with TG 110 in the size range from 250 nm to 1000 nm. When measuring particulate or fibrous materials, the appropriate TG should be selected depending on the size range of particles tested. In line with TG 110, the new TG for nanomaterials includes separate parts for particles and fibres. For the part of this TG which addresses particles, several methods applicable to nanomaterials were reviewed and included to take into account developments since 1981 when the TG 110 was adopted. This TG includes the following methods: Atomic Force Microscopy (AFM), Centrifugal Liquid Sedimentation (CLS)/Analytical Ultracentrifugation (AUC), Dynamic Light Scattering (DLS), Differential Mobility Analysis System (DMAS), (Nano)Particle Tracking Analysis (PTA/NTA), Small Angle X-Ray Scattering (SAXS), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The method Single Particle Inductively Coupled Plasma Mass Spectrometry (sp-ICP-MS) could not be sufficiently validated within the interlaboratory comparison (ILC) carried out for the different methods in this TG (see also paragraph 6 for further details on the ILC). Applicability of sp-ICP-MS is strongly limited to nanomaterials with high mass values in combination with a sufficiently high particle size. However, the general method ICP-MS is widely used and the sp-mode for the size measurement of specific nanomaterials was successfully performed in ILCs elsewhere. The method is therefore included in the Appendix Part C of this TG, which further details the limitations of sp-ICP-MS. For measuring the diameter and length of fibres, analysing images captured with electron microscopy is currently the only method available. This TG includes Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). To test the validity of this TG, an ILC was performed. Test materials were chosen to reflect a broad range of nanomaterial classes, e.g. metals, metal oxides, polymers and carbon materials. Where possible, well-characterised test materials were used. Additionally, the test materials were chosen to reflect a broad range of sizes representing the size range 1 nm to 1000 nm. Specifically for fibres, a broad range of aspect ratios was included (length/diameter of 3 to > 50). Some of the test materials used are commercially available and further references are given in the validation report of the ILC. Sample preparation for physical chemical characterisation is critical for all listed methods. Due to the differences between individual nanomaterials and due to the wide range of individual material properties it is impossible to have a generic protocol to obtain the best possible sample preparation for every nanomaterial. Therefore, a generic protocol on sample preparation is not part of this TG. Information on sample preparation is given in the paragraphs 25-29, 33, 34 and 39 for particles and in paragraphs 159) for fibres. Further information on sample preparation of nanomaterials for physical chemical characterisation can be found in the OECD Guidance on Sample Preparation and Dosimetry for the Safety Testing of Manufactured Nanomaterials and elsewhere. KW - Nano KW - Nanomaterial KW - Nanoparticle KW - OECD KW - Test guideline PY - 2022 DO - https://doi.org/10.1787/20745753 SP - 1 EP - 72 PB - Organisation for Economic Co-operation and Development CY - Paris AN - OPUS4-55191 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard A1 - Battig, Alexander A1 - Böhning, Martin A1 - Frasca, Daniele A1 - Schulze, Dietmar A1 - Strommer, Bettina A1 - Tabaka, Weronika A1 - Wachtendorf, Volker T1 - Multifunctional Elastomer/Graphene Nanocomposites N2 - A few layer/multilayer graphene (MLG) with a specific surface area of BET=250 m2/g is proposed as an efficient multifunctional nanofiller for rubbers. The preparation method, i.e., ultrasonically-assisted solution mixing of master batches followed by two-roll milling, strongly influences the dispersion in the elastomeric matrix and is fundamental for the final properties. When homogenously dispersed, single stacks of only approximately 10 graphene sheets, with an aspect ratio of 34, work at low loadings, enabling the replacement of large amounts of carbon black (CB), an increase in efficiency, and a reduction in filler load. The appropriate preparation yielded nanocomposites in which just 3 phr are sufficient to significantly improve the rheological, curing, gas barrier properties, electrical and thermal conductivity, as well as mechanical properties of different rubbers, as shown for chlorine-Isobutylene-Isoprene rubber (CIIR), nitrile-butadiene rubber (NBR), natural rubber (NR), and styrene-butadiene rubber (SBR). 3 phr of MLG tripled the Young’s modulus of CIIR, an effect equivalent to 20 phr of CB. The stronger interactions between MLG and NR or SBR also resulted in a reduction in the elongation at break by 20% and 50%, respectively, while the same parameter was hardly changed for CIIR/MLG and NBR/MLG. CIIR/MLG and NBR/MLG were stiffer but just as defomable than CIIR and NBR. The strong reinforcing effect of 3 phr MLG was confirmed by the increase of greater than 10 Shore A in hardness. MLG reduces gas permeability, increases thermal and electrical conductivities, and retards flammability, the latter shown by the reduction in heat release rate in the cone calorimeter. We investigated MLG also as a synergist for reducing the aluminium trihydrate loading in flame retardant hydrogenated acrylonitrile-butadiene (HNBR), polybutadiene chloroprene (BR/CR), and chlorosulfonated polyethylene rubber(CSM). The higher the nanofiller concentration is, the greater the improvement in the properties. For instance, the permeability decreased by 30% at 3 phr of MLG, 50% at 5 phr and 60% at 10 phr, respectively. Moreover, the MLG nanocomposites improve stability of mechanical properties against the effects of weathering. In key experiments an increase in UV-absorption and a pronounced radical scavenging were proved as stabilizing mechanisms. In a nutshell, MLG is an efficient multifunctional nanofiller ready to be used for innovative rubber development. T2 - 19th European Polymer Congress, EPF 2022 CY - Prague, Czech Republic DA - 26.06.2022 KW - Graphene KW - Nanocomposite KW - Rubber KW - Elastomer PY - 2022 AN - OPUS4-55196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Darvishi Kamachali, Reza T1 - Melting upon Coalescence of Solid Nanoparticles N2 - The large surface-to-volume ratio of nanoparticles is understood to be the source of many interesting phenomena. The melting temperature of nanoparticles is shown to dramatically reduce compared to bulk material. Yet, at temperatures below this reduced melting point, a liquid-like atomic arrangement on the surface of nanoparticles is still anticipated to influence its properties. To understand such surface effects, here, we study the coalescence of Au nanoparticles of various sizes using molecular dynamics simulations. Analysis of the potential energy and Lindemann index distribution across the nanoparticles reveals that high-energy, high-mobility surface atoms can enable the coalescence of nanoparticles at temperatures much lower than their corresponding melting point. The smaller the nanoparticles, the larger the difference between their melting and coalescence temperatures. For small enough particles and/or elevated enough temperatures, we found that the coalescence leads to a melting transition of the two nominally solid nanoparticles, here discussed in relation to the heat released due to the surface reduction upon the coalescence and the size dependence of latent heat. Such discontinuous melting transitions can lead to abrupt changes in the properties of nanoparticles, important for their applications at intermediate temperatures. KW - Nanoparticles KW - Molecular Dynamics KW - Surface-induced Melting PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552183 DO - https://doi.org/10.3390/solids3020025 VL - 3 IS - 2 SP - 361 EP - 373 PB - MDPI AN - OPUS4-55218 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strommer, Bettina A1 - Böhning, Martin A1 - Schulze, Dietmar A1 - Schartel, Bernhard A1 - Agudo Jácome, Leonardo T1 - Anisotropy in natural rubber / graphene nanocomposites N2 - The incorporation of nanoscale particles into elastomers enable a boost in performance and/or a distinct reduction of conventional filler loadings due to their high surface to volume ratio. 2D layered nanoparticles like graphene and graphene-related materials provide a great potential as effective fillers in rubber, especially by enhancing mechanical and barrier properties. The type and properties of the nanoparticles, their interface and the elastomeric matrix materials influence the technical behavior, and therefore the potential application fields of such rubber nanocomposites. Especially crucial for the efficiency of the nanofiller, however, is its best possible incorporation into the elastomer. The dispersing of nanoparticles without agglomerates usually constitutes a challenge when using conventional two-roll milling or internal mixing. Academic approaches for highly dispersed nanocomposites solve this problem but are often energy and time consuming with no feasible scale up possibility. Therefore, an ultrasonic assisted NR latex premixing process was established to produce highly filled masterbatches, enabling the main processing with conventional rubber processing techniques. Two carbon-based nanoparticles with similar specific surface areas were investigated and incorporated in natural rubber as nanocomposites: A commercially available multilayer graphene (MLG) and a nanoscale carbon black (nCB). The mentioned premixed masterbatches were further processed to nanocomposites by the addition of matrix NR, two-roll milling, and hot pressing (vulcanization). By this procedure an increase in Young’s modulus of 157% (MLG) and 71% (nCB) could be obtained at a concentration level of 3 phr. As anisotropic material behavior was observable for the nanocomposites containing MLG, different measurement methods were investigated to quantify the orientation of the nanoparticles in the nanocomposites: Sorption measurements (swelling in 2 dimensions), hardness and dynamical mechanical analysis (in-plane vs. cross-plane), X-Ray diffraction and transmission and scanning electron microscopy. T2 - DKT IRC 21 CY - Nuremberg, Germany DA - 27.06.2022 KW - Processing KW - Elastomers KW - Nanocomposites KW - Graphene KW - Orientation KW - Anisotropy PY - 2022 AN - OPUS4-55205 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Clark, P.C.J A1 - Andresen, Elina A1 - Sear, M. J. A1 - Favaro, M. A1 - Girardi, L. A1 - van de Krol, R. A1 - Resch-Genger, Ute A1 - Starr, D.E. T1 - Quantification of the Activator and Sensitizer Ion Distributions in NaYF4:Yb3+, Er3+ Upconverting Nanoparticles Via Depth-Profiling with Tender X-Ray Photoemission N2 - The spatial distribution and concentration of lanthanide activator and sensitizer dopant ions are of key importance for the luminescence color and efficiency of upconverting nanoparticles (UCNPs). Quantifying dopant ion distributions and intermixing, and correlating them with synthesis methods require suitable analytical techniques. Here, X-ray photoelectron spectroscopy depth-profiling with tender X-rays (2000–6000 eV), providing probe depths ideally matched to UCNP sizes, is used to measure the depth-dependent concentration ratios of Er3+ to Yb3+, [Er3+]/[Yb3+], in three types of UCNPs prepared using different reagents and synthesis methods. This is combined with data simulations and inductively coupled plasma-optical emission spectroscopy (ICP-OES) measurements of the lanthanide ion concentrations to construct models of the UCNPs’ dopant ion distributions. The UCNP sizes and architectures are chosen to demonstrate the potential of this approach. Core-only UCNPs synthesized with XCl3·6H2O precursors (β-phase) exhibit a homogeneous distribution of lanthanide ions, but a slightly surface-enhanced [Er3+]/[Yb3+] is observed for UCNPs prepared with trifluroacetate precursors (α-phase). Examination of Yb-core@Er-shell UCNPs reveals a co-doped, intermixed region between the single-doped core and shell. The impact of these different dopant ion distributions on the UCNP's optical properties is discussed to highlight their importance for UCNP functionality and the design of efficient UCNPs. KW - Shell KW - Nanomaterial KW - Nano KW - Upconversion nanoparticle KW - Lanthanide KW - Photoluminescence KW - Quantum yield KW - Photophysics KW - Excitation power density KW - Surface KW - Coating KW - Core-shell KW - XPS KW - Intermixing KW - HAXPES KW - Method PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552075 DO - https://doi.org/10.1002/smll.202107976 SN - 1613-6813 SP - 1 EP - 13 PB - Wiley-VCH-Verlag CY - Weinheim, Germany AN - OPUS4-55207 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tavernaro, Isabella A1 - Nirmalananthan-Budau, Nithiya A1 - Resch-Genger, Ute 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 - GEN A1 - Pauw, Brian Richard A1 - Smales, Glen Jacob T1 - Raw and processed X-ray scattering datasets for: "Entering a new dimension in powder processing for advanced ceramics shaping" N2 - This dataset is a complete set of raw, processed and analyzed data, associated with the manuscript mentioned in the title. All associated metadata and processing history has been added. Particle size distribution analyses using McSAS are included as well. The samples consisted of a 4.2 mass% dispersion of yttria-stabilized zirconia nanoparticles in a cross-linked matrix. The measurements show a good dispersion with minimal agglomeration. The wide-angle region shows diffraction information consistent with zirconia. KW - X-ray scattering KW - Nanocomposite KW - Ceramic microprinting KW - Yttria-stabilized zirconia KW - SAXS KW - Nanomaterials KW - Two-photon polymerization KW - Transparency KW - Mechanical testing PY - 2023 DO - https://doi.org/10.5281/zenodo.7498647 PB - Zenodo CY - Geneva AN - OPUS4-56766 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan A1 - Reed, B.P. A1 - Pollard, A. A1 - Clifford, C. A1 - Chemello, Giovanni T1 - XPS of GR2M N2 - The activities of ISO-G-Scope are presented. The influence of the sample preparation and the results of XPS/HAXPES measurements are discussed. T2 - Graphene Workshop @ ISO TC 229 Meeting CY - Teddington, UK DA - 16.11.2022 KW - Graphene related materials KW - X-ray photoelectron spectroscopy KW - Sample preparation KW - Hard X-ray photoelectron spectroscopy PY - 2022 AN - OPUS4-56434 LA - eng 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 - GEN A1 - Pauw, Brian Richard T1 - McSAS3 N2 - McSAS3 is a refactored version of the original McSAS (see DOI 10.1107/S1600576715007347). This software fits scattering patterns to obtain size distributions without assumptions on the size distribution form. The refactored version has some neat features: - Multiprocessing is included, spread out over as many cores as number of repetitions! - Full state of the optimization is stored in an organized HDF5 state file. - Histogramming is separate from optimization and a result can be re-histogrammed as many times as desired. - SasModels allow a wide range of models to be used - If SasModels does not work (e.g. because of gcc compiler issues on Windows or Mac), an internal sphere model is supplied - Simulated data of the scattering of a special shape can also be used as a McSAS fitting model. Your models are infinite! - 2D fitting also works. KW - X-ray scattering KW - Polydispersity KW - Monte carlo KW - Scattering pattern analysis KW - Analysis approach KW - Neutron scattering KW - Automation KW - Command line PY - 2023 DO - https://doi.org/10.6084/m9.figshare.21814128.v1 PB - Digital Science CY - Cambridge, MA, USA AN - OPUS4-56787 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Laskina, Sofya T1 - Computing the forward and inverse problem of X-ray scattering N2 - Continuing progress in the field of X-ray scattering methods empowers scientists with new possibilities to capture the most important piece of information about the structure of the sample - its 3D electron density. Although the first methods appeared almost a century ago, recovering the density structure of a sample is still very problematic. Most avail-able imaging techniques transform a 3D electron density of a realspace structure into the 2D Fourier Transform of the intensity of scattered waves in the reciprocal space. This process causes a loss of information. Firstly, instead of a 3D sample, a 2D image is created, and secondly, the phase information of the scattered waves is lost. The latter is known as the ”phase problem” and poses a serious obstacle on a way to recover a 3D electron density. In this work, we draw attention to the problem of forward and inverse Small Angle X-Ray Scattering. In the first, forward, part, we rethink the existing pipelines to computationally simulate such scattering experiments. Although there are efficient implementations of fast Fourier transformation, they often have some drawbacks. For instance, to calculate a 3D fast Fourier transform it is required to place its density in the RAM. For high-resolution structures of size > 1024 3 , this becomes very problematic, as the whole density structure requires more than 16 GB of memory. CUDA solution allows for a very fast and parallelizable implementation of high-resolution data on hundreds of last-generation machines. Such computations are very pricy and inaccessible for most scientists. To bypass this limitation, we propose a solution for a split-up 3D fast Fourier transform, which is implemented as a sequence of 2D and 1D operations. We compare our implementation on the simulated 3D shapes and show the result of a proof-of-concept on 4096 3 Metallorganic framework density structure. In the second, inverse problem, we train an invertible neural network, that given scattering data can predict the shape and its parameters. The architecture is built such, that the inverse problem is learned together with the forward process - the Fourier Transformation. We achieved very good results with this architecture, nonetheless, further testing is required, as the current training set only encompasses three simple shapes: sphere, hard sphere and cylinder. All code to reproduce and analyze the results is available at https: //github.com/sofyalaski/SAXS-simulations. KW - Machine Learning KW - SAXS KW - DFT PY - 2023 SP - 1 EP - 76 PB - Freie Universität Berlin CY - Berlin AN - OPUS4-56798 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Miropoltsev, M. A1 - Wegner, Karl David A1 - Häusler, I. A1 - Hodoroaba, Vasile-Dan A1 - Resch-Genger, Ute T1 - Influence of Hydrophilic Thiol Ligands of Varying Denticity on the Luminescence Properties and Colloidal Stability of Quaternary Semiconductor Nanocrystals N2 - Binary photoluminescent semiconductor nanocrystals (quantum dots, QDs) are one of the best studied fluorescent nanomaterials, and their unique optoelectronic properties paved the road to many applications in (bio)nanophotonics, optoelectronics, and photovoltaics. However, concerns related to their toxic constituents like cadmium or lead and the emerging interest in greener chemistry synthesis approaches hamper their future applicability. Interesting alternatives for some applications like biosensing or bioimaging are heavy-metal-free ternary QDs like AgInS2 (AIS), CuInS2 (CIS), and quaternary QDs such as AIS-ZnS (ZAIS). In this context, we explored the effect of ligand denticity on the organic-to-aqueous phase transfer of oleylamine-stabilized ZAIS QDs with the hydrophilic ligands mercaptopropionic acid (MPA), dihydrolipoic acid (DHLA), and 3-mercapto-2,2-bis(mercaptomethyl)propanoic acid (3MPA), bearing mono-, bi-, and trialkyl thiol groups. Spectroscopic studies of the resulting water-dispersible ZAIS QDs revealed a considerable influence of ligand denticity and ligand-to-QD ratio on the spectral position and width (FWHM; full width at half-maximum) of the photoluminescence (PL) bands, the PL quantum yields (PL QY), and the PL decay kinetics. Thiol capping and phase transfer resulted in a loss in PL by at least a factor of 2. The ligand-induced PL quenching observed particularly for ligands bearing two or three thiol groups was attributed to the facilitated formation of surface-bound disulfides. The best colloidal stability under high dilution conditions was observed for 3MPA. KW - Quantum dots KW - Ligand exchange KW - Lifetime analysis KW - Thiols PY - 2022 DO - https://doi.org/10.1021/acs.jpcc.2c05342 SN - 1932-7447 VL - 126 IS - 47 SP - 20101 EP - 20113 PB - ACS Publications AN - OPUS4-56707 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dhamo, Lorena A1 - Wegner, Karl David A1 - Würth, Christian A1 - Häusler, I. A1 - Hodoroaba, Vasile-Dan A1 - Resch-Genger, Ute T1 - Assessing the influence of microwave-assisted synthesis parameters and stabilizing ligands on the optical properties of AIS/ZnS quantum dots N2 - Luminescent semiconductor quantum dots (QDs) are frequently used in the life and material sciences as reporter for bioimaging studies and as active components in devices such as displays, light-emitting diodes, solar cells, and sensors. Increasing concerns regarding the use of toxic elements like cadmium and lead, and hazardous organic solvents during QD synthesis have meanwhile triggered the search for heavy-metal free QDs using green chemistry syntheses methods. Interesting candidates are ternary AgInS2 (AIS) QDs that exhibit broad photoluminescence (PL) bands, large effective Stokes shifts, high PL quantum yields (PL QYs), and long PL lifetimes, which are particularly beneficial for applications such as bioimaging, white light-emitting diodes, and solar concentrators. In addition, these nanomaterials can be prepared in high quality with a microwave-assisted (MW) synthesis in aqueous solution. The homogeneous heat diffusion and instant temperature rise of the MW synthesis enables a better control of QD nucleation and growth and thus increases the batch-to-batch reproducibility. In this study, we systematically explored the MW synthesis of AIS/ZnS QDs by varying parameters such as the order of reagent addition, precursor concentration, and type of stabilizing thiol ligand, and assessed their influence on the optical properties of the resulting AIS/ZnS QDs. Under optimized synthesis conditions, water-soluble AIS/ZnS QDs with a PL QY of 65% and excellent colloidal and long-term stability could be reproducible prepared. KW - Quantum dots KW - Microwave-assisted synthesis KW - AgInS KW - Aqueous synthesis PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567091 DO - https://doi.org/10.1038/s41598-022-25498-3 SN - 2045-2322 VL - 12 IS - 1 SP - 1 EP - 11 PB - Nature Publishing Group CY - London AN - OPUS4-56709 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Harald A1 - Kuchenbecker, Petra A1 - Löhmann, Oliver A1 - Rühle, Bastian A1 - Resch-Genger, Ute A1 - Hodoroaba, Vasile-Dan T1 - Schwerpunktthema nano@BAM – Projekt Nanoplattform N2 - Darstellung der Digitalisierung im Rahmen des Themenfeldprojektes Nanoplattform. Es werden beleuchtet: BAM-DataStore, Voraussetzungen für ELNs, Möglichkeitenvon OpenBIS, NFDI-Antrag InnoMatSafety, Digitalisierung von Workflows. T2 - BAM Beiratssitzung Umwelt CY - Online meeting DA - 11.03.2022 KW - Nano KW - Elektronisches Laborbuch KW - Workflows KW - Digitalisierung KW - Standardarbeitsanweisungen PY - 2022 AN - OPUS4-56756 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn A1 - Ayerdi, Jon J. A1 - Slachciak, Nadine A1 - Gradt, Thomas A1 - Krüger, Jörg A1 - Zabala, A. A1 - Spaltmann, Dirk T1 - Ultrakurzpulslaser induzierte Oxidschichten zur Reduktion von Reibung und Verschleiß auf Metalloberflächen N2 - Die Reduktion von Reibung und Verschleiß in technischen Systemen bietet ein großes Potenzial zur Reduktion von CO2-Emissionen. Dieser Beitrag diskutiert die Erzeugung und tribologische Charakterisierung von Ultrakurzpuls-generierten Nano- und Mikrostrukturen auf Metallen (Stahl, Titan). Besonderes Augenmerk wird dabei auf die Rolle der laserinduzierten Oxidschicht im Zusammenspiel mit verschleißreduzierenden Additiven in ölbasierten Schmiermitteln gerichtet. T2 - Workshop "Nachhaltigkeit durch Tribologische Schichten" - Europäische Forschungsgesellschaft Dünne Schichten e.V. CY - Karlsruhe, Germany DA - 17.05.2022 KW - Laser-induzierte periodische Oberflächenstrukturen KW - Reibungsreduktion KW - Verschleißreduktion KW - Oberflächenmodifikation KW - Oxidation KW - Additive PY - 2022 AN - OPUS4-54849 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bawadkji, O. A1 - Cherri, M. A1 - Schäfer, A. A1 - Herziger, S. A1 - Nickl, Philip A1 - Achazi, K. A1 - Donskyi, Ievgen A1 - Adeli, M. A1 - Haag, R. T1 - One-pot covalent functionalization of 2D black phosphorus by anionic ring opening polymerization N2 - In this work, a one-pot approach for the covalent functionalization of few-layer black phosphorus (BP) by anionic ring opening polymerization of glycidol to obtain multifunctional BP-polyglycerol (BP-PG) with high amphiphilicity for near-infrared-responsive drug delivery and biocompatibility is reported. Straightforward synthesis in combination with exceptional biological and physicochemical properties designates functionalized BP-PG as a promising candidate for a broad range of biomedical applications. KW - 2D nanomaterial KW - Amphiphilicity KW - Black phosphorus KW - Hyperbranched KW - Polyglycerol KW - Water dispersibility PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568833 DO - https://doi.org/10.1002/admi.202201245 SN - 2196-7350 VL - 9 SP - 1 EP - 8 PB - Wiley-VCH CY - Weinheim AN - OPUS4-56883 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn A1 - Florian, Camilo A1 - Mezera, Marek A1 - Wasmuth, Karsten A1 - Richter, Anja A1 - Schwibbert, Karin A1 - Krüger, Jörg A1 - Müller, F. A. A1 - Gräf, S. T1 - A brief survey on open questions about laser-induced periodic surface structures N2 - The processing of laser-induced periodic surface structures (LIPSS) represents a simple and robust way for the nanostructuring of solids that allows creating a wide range of surface functionalities featuring applications in optics, tribology, medicine, energy technologies, etc. While the currently available laser and scanner technology already allows surface processing rates at the m2/min level, industrial applications of LIPSS are sometimes hampered by the complex interplay between the nanoscale surface topography and the specific surface chemistry. This typically manifests in difficulties to control the processing of LIPSS and in limitations to ensure the long-term stability of the created surface functions. This presentation aims to identify some unsolved scientific problems related to LIPSS, discusses the pending technological limitations, and sketches the current state of theoretical modelling. Hereby, it is intended to stimulate further research and developments in the field of LIPSS for overcoming these limitations and for supporting the transfer of the LIPSS technology into industry. T2 - E-MRS Spring Meeting 2022 CY - Online meeting DA - 30.05.2022 KW - Laser-induced periodic surface structures (LIPSS) KW - Surface functionalization KW - Industrial applications KW - Biofilm growth PY - 2022 AN - OPUS4-54929 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Richter, Anja A1 - Buchberger, G. A1 - Stifter, D. A1 - Duchoslav, J. A1 - Hertwig, Andreas A1 - Bonse, Jörn A1 - Heitz, J. A1 - Schwibbert, Karin T1 - Reducing Escherichia coli adhesion to PET by modulating spatial periods of laser-induced surface nanoripples N2 - Using nanofiber-like cell appendages, secreted proteins and sugars, bacteria can establish initial surface contact followed by irreversible adhesion and the formation of multicellular biofilms. Here, the stabilizing extracellular biofilm matrix together with physiological changes on the single cell level leads to an increased resilience towards harsh environmental conditions, antimicrobials, the host immune response and established cleaning procedures. Persistent microbial adhesion on e.g., medical implants, in water supply networks or food-processing industry is often associated with chronic inflammation, nosocomial and foodborne infections, enhanced biofouling and product contamination. To prevent persistent microbial colonization, antibacterial surface strategies often target the initial steps of biofilm formation and impede adhesion of single cells before a mature biofilm is being formed. While chemical coatings have been widely used, their restricted biocompatibility for eukaryotic cells and attenuated antibacterial-effects due to compound release limit their areas of application and alternative strategies focus on modified surfaces topographies to impede bacterial adhesion. In this work, we used ns-UV laser treatment (wavelength 248 nm and a pulse duration of 20 ns) to generate laser-induced periodic surface structures (LIPSS) with different submicrometric periods ranging from ~210 to ~610 nm on commercial poly(ethylene terephthalate) (PET) foils. Following structurally and chemically analyses, PET samples were subjected to bacterial colonization studies with Escherichia coli TG1, a bacterial test strain with a strong biofilm formation capacity due to the formation of nanofiber-like cell-appendages (pili). Bacterial adhesion tests revealed that E. coli repellence decisively depends on the spatial periods of the LIPSS with the strongest reduction (~91%) in cell adhesion observed for LIPSS periods of 214 nm. Scanning electron microscopy and additional biofilm studies using a pili-deficient E. coli TG1 strain revealed the importance of extracellular appendages in the bacterial repellence observed here, thus, pointing out new antibiotics-free strategies for antibacterial surfaces by impeding nanofiber-mediated bacterial adhesion. T2 - E-MRS Spring Meeting 2022 CY - Online meeting DA - 30.05.2022 KW - Laser-induced periodic surface structures (LIPSS) KW - Bacterial adhesion tests KW - Bacteria repellent surfaces KW - Polymer foils KW - E. coli PY - 2022 AN - OPUS4-54930 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn A1 - Mirabella, Francesca A1 - Mezera, Marek A1 - Weise, Matthias A1 - Sahre, Mario A1 - Wasmuth, Karsten A1 - Hertwig, Andreas A1 - Krüger, Jörg A1 - Hodoroaba, Vasile-Dan T1 - Chemical and structural changes at the surface of titanium materials upon irradiation with near-infrared ultrashort laser pulses N2 - Due to its large strength-to-weight ratio and excellent biocompatibility, titanium materials are of paramount importance for medical applications, e.g. as implant material for protheses. In this work, the evolution of various types of laser-induced micro- and nanostructures emerging on titanium or titanium alloys upon irradiation by near-infrared ultrashort laser pulses (925 fs, 1030 nm) in air environment is studied for various laser fluence levels, effective number of pulses and at different pulse repetition rates (1 – 400 kHz). The morphologies of the processed surfaces were systematically characterized by optical and scanning electron microscopy (OM, SEM). Complementary white-light interference microscopy (WLIM) revealed the corresponding surface topographies. Chemical and structural changes were analysed through depth-profiling time-of-flight secondary ion mass spectrometry (TOF-SIMS) and X-ray diffraction (XRD) analyses. The results point towards a remarkable influence of the laser processing parameters on the surface topography, while simultaneously altering the near-surface chemistry via laser-induced oxidation effects. Consequences for medical applications are outlined. T2 - E-MRS Spring Meeting 2022 CY - Online meeting DA - 30.05.2022 KW - Laser-induced periodic surface structures (LIPSS) KW - Surface functionalization KW - ToF-SIMS KW - Chemical analysis KW - Titanium PY - 2022 AN - OPUS4-54931 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - VIDEO A1 - Schwibbert, Karin A1 - Richter, Anja A1 - Bonse, Jörn T1 - BioCombs4Nanofibers: From nanofibers over spiders to bacteria N2 - This 6 minute long MP4-video presents some key results of the European research project "BioCombs4Nanofibers" to the broader public. Inspired by nature, some concepts of certain types of spiders are transferred to technology in order to develop bacteria-repellent surfaces through laser surface nanostructuring. Funding notice: This study was funded by the European Union's research and innovation program under the FET Open grant agreement No. 862016 (BioCombs4Nanofibers, http://biocombs4nanofibers.eu). KW - Antiadhesive surfaces KW - Laser-induced periodic surface structures (LIPSS) KW - Cribellate spiders KW - Bacterial adhesion tests KW - Bacteria-repellent surfaces PY - 2022 UR - https://download.jku.at/org/7kM/xyU/BioCombs4Nanofibers/D5.6_video%20for%20the%20broader%20public_23.03.2022.mp4 UR - https://www.jku.at/en/biocombs4nanofibers/dissemination/ DO - https://doi.org/10.26272/opus4-54939 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-54939 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Srivastava, Priyanka A1 - Tavernaro, Isabella A1 - Scholtz, Lena A1 - Genger, C. A1 - Welker, P. A1 - Schreiber, Frank A1 - Meyer, Klas A1 - Resch-Genger, Ute T1 - Dual color pH probes made from silica and polystyrene nanoparticles and their performance in cell studies N2 - Ratiometric green–red fluorescent nanosensors for fluorometrically monitoring pH in the acidic range were designed from 80 nm-sized polystyrene (PS) and silica (SiO2) nanoparticles (NPs), red emissive reference dyes, and a green emissive naphthalimide pH probe, analytically and spectroscopically characterized, and compared regarding their sensing performance in aqueous dispersion and in cellular uptake studies. Preparation of these optical probes, which are excitable by 405 nm laser or LED light sources, involved the encapsulation of the pH-inert red-fuorescent dye Nile Red (NR) in the core of self-made carboxylated PSNPs by a simple swelling procedure and the fabrication of rhodamine B (RhB)-stained SiO2-NPs from a silane derivative of pH-insensitive RhB. Subsequently, the custom-made naphthalimide pH probe, that utilizes a protonation-controlled photoinduced electron transfer process, was covalently attached to the carboxylic acid groups at the surface of both types of NPs. Fluorescence microscopy studies with the molecular and nanoscale optical probes and A549 lung cancer cells confirmed the cellular uptake of all probes and their penetration into acidic cell compartments, i.e., the lysosomes, indicated by the switching ON of the green naphthalimide fluorescence. This underlines their suitability for intracellular pH sensing, with the SiO2-based nanosensor revealing the best performance regarding uptake speed and stability. KW - Sensors KW - Silica and polystyrene nanoparticles KW - pH probe KW - Fluorescence spectroscopy KW - Cell studies KW - Dye KW - Particle synthesis PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569198 DO - https://doi.org/10.1038/s41598-023-28203-0 SN - 2045-2322 VL - 13 IS - 1 SP - 1321 EP - 1336 PB - Nature CY - London AN - OPUS4-56919 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reichelt, Manuel A1 - Cappella, Brunero T1 - Atomic force microscope study of friction at the submicron-scale during tribotests with self-mated steel N2 - Friction at the microscale during reciprocal sliding tribotests was studied for the first time with self-mated steel (100Cr6/AISI 52100) taking advantage of an atomic force microscope (AFM). To this aim, microsized steel particles were glued to the AFM-cantilever and employed as colloidal tips to perform tribotests on a steel disc. The torsion of the cantilever, which correlates with the friction force, was measured during the tests. Few tests with the same load did not yield any wear and show that the load and adhesion contributions to friction stay constant when the shape of the test particle does not change. Most of the presented tribotests engendered wear. For those tests, the increase of friction during the tribotests was attributed to the emerging plowing contribution. Furthermore, analysis of both torsion and local slope gives information on the creation of wear particles and their influence on friction. KW - Friction KW - Microtribology KW - Sliding KW - Wear PY - 2022 DO - https://doi.org/10.1115/1.4054251 VL - 144 IS - 10 SP - 1 EP - 9 PB - ASME AN - OPUS4-54839 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 - Kuchenbecker, Petra T1 - Bestimmung der Partikelgrößenverteilung mittels Zentrifugen-Sedimentationsverfahren nach ISO 13318-2 (Küvette) N2 - Im Vortrag werden das Messprinzip des Zentrifugen-Sedimentationsverfahrens erläutert und die Anforderungen der zugrundeliegenden Normen diskutiert. Es schließen sich umfangreiche Ausführungen zur praktischen Durchführung der Messung, insbesondere auch zu den vorbereitenden Arbeiten, sowie zur Auswertung der Rohdaten an. Gezeigt werden die Validierung sowie ein Beispiel zur regelmäßigen Verifizierung des Verfahrens. Nach Beispielen und Vergleichen zu Ergebnissen mit anderen Messverfahren, wird das Verfahren in einer Zusammenfassung bewertet. T2 - Seminar Rheologie und Stabilität von dispersen Systemen CY - Potsdam, Germany DA - 09.05.2022 KW - Nano powder KW - Cetrifugal Liquid Sedimentation CLS KW - Particle size determination PY - 2022 AN - OPUS4-54863 LA - deu 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 - Pauw, Brian Richard A1 - Smales, Glen Jacob T1 - Small-angle scattering data analysis round robin dataset - Original for participants N2 - These are four datasets that were made available to the participants of the Small-angle Scattering data analysis round robin. The intent was to find out how comparable results from different researchers are, who analyse exactly the same processed, corrected dataset. In this repository, there are: 1) a PDF document with more details for the study, 2) the datasets for people to try and fit, 3) an Excel spreadsheet to document the results. Datasets 1 and 2 were modified from: Deumer, Jerome, & Gollwitzer, Christian. (2022). npSize_SAXS_data_PTB (Version 5) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.5886834 Datasets 3 and 4 were collected in-house on the MOUSE instrument. KW - Round robin KW - SAXS KW - Small angle scattering KW - SANS KW - X-ray KW - Neutron KW - Human factor KW - Data analysis KW - Data fitting KW - Human influence PY - 2023 DO - https://doi.org/10.5281/zenodo.7506365 PB - Zenodo CY - Geneva AN - OPUS4-56799 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sachse, René A1 - Pflüger, Mika A1 - Velasco Vélez, Juan Jesús A1 - Sahre, Mario A1 - Radnik, Jörg A1 - Bernicke, Michael A1 - Bernsmeier, Denis A1 - Hodoroaba, Vasile-Dan A1 - Krumrey, Michael A1 - Strasser, Peter A1 - Kraehnert, Ralph A1 - Hertwig, Andreas T1 - Operando electrochemical spectroscopic ellipsometry: Material properties of highly active mesoporous IrO IrOxfilms revealed under realistic OER conditions N2 - In the face of rising energy demand and the impending climate change the development of a sustainable, fossil-free fuel and chemical production is of global importance. One possible goal is the development of electrochemical conversion processes using catalysts. Porous materials play an important role in such energy applications. The activity and stability of each catalyst is highly dependent on the properties of the coating, i.e., phase composition, crystallinity, accessible surface area, and many other factors. The key to the development of improved catalysts is a better understanding of the relations between their performance, stability and physico-chemical properties. However, the complex morphology of such catalysts constitutes a challenge even for modern analytical techniques. Spectroscopic ellipsometry (SE) is a versatile method for studying material properties by using appropriate models (e.g., film thickness, optical and electronic properties). Ellipsometric models need to be validated in order to produce accurate results. In a first step, the model for the ellipsometric fit studies of a calcination series of mesoporous iridium oxide films (300 – 600 °C) was investigated and validated with respect to their material properties.[4] The information on electronic structure of the catalysts shows a direct correlation with electrochemical activities. The development of an environmental electrochemical cell offers the possibility of investigations under operando conditions. Thus, changes in optical and electronic properties can be induced and monitored during the electrocatalytic oxygen evolution reaction. T2 - 9th International Conference on Spectroscopic Ellipsometry CY - Beijing, China DA - 22.05.2022 KW - Mesoporous iridium oxide films KW - Non-destructive operando analysis KW - Oxygen evolution reaction KW - Spectroscopic ellipsometry PY - 2022 AN - OPUS4-54915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Smales, Glen Jacob A1 - Hahn, Marc Benjamin A1 - Hallier, Dorothea C. A1 - Seitz, H. T1 - X-ray scattering datasets and simulations associated with the publication "Bio-SAXS of single-stranded DNA-binding proteins: Radiation protection by the compatible solute ectoine" N2 - This dataset contains the processed and analysed small-angle X-ray scattering data associated with all samples from the publications "Bio-SAXS of Single-Stranded DNA-Binding Proteins: Radiation Protection by the Compatible Solute Ectoine" (https://doi.org/10.1039/D2CP05053F). Files associated with McSAS3 analyses are included, alongside the relevant SAXS data, with datasets labelled in accordance to the protein (G5P), its concentration (1, 2 or 4 mg/mL), and if Ectoine is present (Ect) or absent (Pure). PEPSIsaxs simulations of the GVP monomer (PDB structure: 1GV5 ) and dimer are also included. TOPAS-bioSAXS-dosimetry extension for TOPAS-nBio based particle scattering simulations can be obtained from https://github.com/MarcBHahn/TOPAS-bioSAXS-dosimetry which is further described in https://doi.org/10.26272/opus4-55751. This work was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under grant number 442240902 (HA 8528/2-1 and SE 2999/2-1). We acknowledge Diamond Light Source for time on Beamline B21 under Proposal SM29806. This work has been supported by iNEXT-Discovery, grant number 871037, funded by the Horizon 2020 program of the European Commission. KW - SAXS KW - Radiation protection KW - Microdosimetry KW - G5P KW - Ectoine KW - DNA-Binding protein PY - 2023 DO - https://doi.org/10.5281/zenodo.7515394 PB - Zenodo CY - Geneva AN - OPUS4-56811 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chemello, Giovanni A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg T1 - Characterization of Graphene using HAXPES N2 - Since its discovery, graphene has got growing attention in the industrial and application research due to its unique properties . However, graphene has not been yet implemented into the industrial market, in particularly due to the difficulty of properly characterizing this challenging material. As most of other nanomaterials, graphene’s properties are closely linked to its chemical and structural properties, such as number of layers, flake thickness, degree of functionalisation and C/O ratio. For the commercialization, suitable procedures for the measurement and characterization of the ultrathin flakes, of lateral dimensions in the range from µm to tens of µm, are essential.Surface chemical methods, especially XPS, have an outstanding role of providing chemical information on the composition. Thereby, one well-known problem for surface analytical methods is the influence of contamination on the composition as in the case of adventitious carbon. The differentiation between carbon originated from the contamination or from the graphene sample itself is often not obvious, which can lead to altered results in the determination of the composition. To overcome this problem, Hard Energy X-ray Photoelectron Spectroscopy (HAXPES) offers new possibilities due to its higher information depth. Therefore, XPS measurement obtained with Al Kα radiation (E = 1486. 6 eV) were compared with analyses performed with a Cr Kα (E = 5414. 8 eV) excitation on functionalized graphene samples. Differences are discussed in terms of potential carbon contamination, but also of oxygen on the composition of the samples. Measurements are performed on O-, N- and F-functionalized graphene. Different preparation procedures (powder, pellet, drop cast from liquid suspension) will be also discussed, correlation of the results with the flakes morphology as well as their validation with other independent methods are in progress. T2 - ECASIA 2022 CY - Limerick, Ireland DA - 29.05.2022 KW - Graphene KW - Functionalized graphene KW - Depth profiling PY - 2022 AN - OPUS4-56814 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Pauw, Brian Richard T1 - The SPONGE v.1.0.0: Modeling scattering of shapes by STL input, with absolute intensities and size distribution. N2 - Simulates X-ray and Neutron scattering patterns from arbitrary shapes defined by STL files. Features: - Uses multithreading to compute a number of independent solutions, then uses the variance of the results to estimate an uncertainty on the output. - Can be launched from the command line using an excel sheet to define settings, or from a jupyter notebook. - Outputs scattering patterns in absolute units if the contrast is set. - A Gaussian size distribution is available, where the relative scaling of objects for each repetion can be varied. Recommended to be used with limited width (max. 10%) to avoid artefacts. - Writes results with settings to an archival HDF5 file. Application examples: This software has been used in several studies to date. For example, it has been used here to simulate a model scattering pattern for a cuboid shape, which was then fed forward into the McSAS3 analysis program for analyzing scattering patterns of polydisperse cuboids. A second use is here, where it was used for the modeling of flattened helices. In this paper, scattering pattern features could be matched with particular morphological changes in the structure. Lastly, this paper has an example where it was used to validate the analytical analysis model, and explore the realistic limits of application of the analytical model. KW - Software KW - Scattering pattern analysis KW - Scattering pattern simulation KW - X-ray KW - Neutron KW - Command-line interface KW - Scattering pattern KW - STL file input KW - Python KW - Arbitrary shapes PY - 2023 DO - https://doi.org/10.6084/m9.figshare.21857130.v1 PB - Digital Science CY - Cambridge, MA, USA AN - OPUS4-56815 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Terborg, R. A1 - Boehm, S. A1 - Kim, K. J. T1 - Analysis of elemental composition of Fe1-xNix and Si1-xGex alloy thin films by electron probe microanalysis and micro-focus X-ray fluorescence N2 - The present study reports on results of analysis of the elemental composition of thin films by electron probe microanalysis with energy dispersive (ED-EPMA) X-ray spectrometry in conjunction with the dedicated thin-film analysis software package Stratagem and by X-ray fluorescence in its version with a micro-focus X-ray fluorescence (μ-XRF) source attached to a scanning electron microscope (SEM). Two thin-film systems have been analyzed: Fe1-xNix on silicon wafer and Si1-xGex on Al2O3 substrate, in both cases the layers being grown to a thickness of about 200 nm by ion beam sputter deposition. Samples of five different atomic fractions have been produced and analyzed for each thin-film system. Moreover, reference samples with certified elemental composition and thickness have been also available. This study is part of an interlaboratory comparison organized in the frame of standardization technical committee ISO/TC 201 “Surface chemical analysis.” Two laboratories have been analyzed by ED-EPMA (one laboratory standardless and one laboratory using both standardless and with standards variants) and one laboratory by μ-XRF (standardless and with standards). All the elemental compositions obtained with different methods are in very good agreement for the complete two sets of five samples each. KW - Thin films KW - Elemental composition KW - FeNi KW - SiGe KW - Electron probe microanalysis KW - X-ray Fluorescence PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509262 DO - https://doi.org/10.1002/sia.6834 SN - 0142-2421 VL - 52 IS - 12 SP - 929 EP - 932 PB - John Wiley & Sons Ltd AN - OPUS4-50926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stratakis, E. A1 - Bonse, Jörn A1 - Heitz, J. A1 - Siegel, J. A1 - Tsibidis, G.D. A1 - Skoulas, E. A1 - Papadopoulos, A. A1 - Mimidis, A. A1 - Joel, A.-C. A1 - Comanns, P. A1 - Krüger, Jörg A1 - Florian, C. A1 - Fuentes-Edfuf, Y. A1 - Solis, J. A1 - Baumgartner, W. T1 - Laser engineering of biomimetic surfaces N2 - The exciting properties of micro- and nano-patterned surfaces found in natural species hide a virtually endless potential of technological ideas, opening new opportunities for innovation and exploitation in materials science and engineering. Due to the diversity of biomimetic surface functionalities, inspirations from natural surfaces are interesting for a broad range of applications in engineering, including phenomena of adhesion, friction, wear, lubrication, wetting phenomena, self-cleaning, antifouling, antibacterial phenomena, thermoregulation and optics. Lasers are increasingly proving to be promising tools for the precise and controlled structuring of materials at micro- and nano-scales. When ultrashort-pulsed lasers are used, the optimal interplay between laser and material parameters enables structuring down to the nanometer scale. Besides this, a unique aspect of laser processing technology is the possibility for material modifications at multiple (hierarchical) length scales, leading to the complex biomimetic micro- and nano-scale patterns, while adding a new dimension to structure optimization. This article reviews the current state of the art of laser processing methodologies, which are being used for the fabrication of bioinspired artificial surfaces to realize extraordinary wetting, optical, mechanical, and biological-active properties for numerous applications. The innovative aspect of laser functionalized biomimetic surfaces for a wide variety of current and future applications is particularly demonstrated and discussed. The article concludes with illustrating the wealth of arising possibilities and the number of new laser micro/nano fabrication approaches for obtaining complex high-resolution features, which prescribe a future where control of structures and subsequent functionalities are beyond our current imagination. KW - Biomimetic surfaces KW - Laser processing KW - Surface functionalization KW - Bioinspiration KW - Bionic materials PY - 2020 DO - https://doi.org/10.1016/j.mser.2020.100562 SN - 0927-796X VL - 141 SP - 100562-1 EP - 100562-47 PB - Elsevier B.V. AN - OPUS4-50927 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Donskyi, Ievgen A1 - Chen, Y. A1 - Nickl, Philip A1 - Guday, G. A1 - Qiao, H. A1 - Achasi, K. A1 - Lippitz, Andreas A1 - Unger, Wolfgang A1 - Böttcher, C. A1 - Chen, W. A1 - Adeli, M. A1 - Haag, R. T1 - Self-degrading graphene sheets for tumor therapy N2 - Low biodegradability of graphene derivatives and related health risks are the main limiting factors for their in vivo biomedical applications. Here, we present the synthesis of enzyme-functionalized graphene sheets with self-degrading properties under physiological conditions and their applications in Tumor therapy. The synergistic enzyme cascade glucose oxidase and myeloperoxidase are covalently conjugated to the surface of graphene sheets and two-dimensional (2D) platforms are obtained that can produce sodium hypochlorite from glucose. The enzyme-functionalized graphene sheets with up to 289 nm average size are degraded into small pieces (≤40 nm) by incubation under physiological conditions for 24 h. Biodegradable graphene sheets are further loaded with doxorubicin and their ability for Tumor therapy is evaluated in vitro and in vivo. The laser-triggered release of doxorubicin in combination with the enzymatic activity of the functionalized graphene sheets results in a synergistic antitumor activity. Taking advantage of their neutrophil-like activity, fast biodegradability, high photo- and chemotherapeutic effects, the novel two-dimensional nanoplatforms can be used for tumor therapeutic applications. KW - Graphene KW - Self-degrading KW - Thumor therapy KW - XPS KW - NEXAFS PY - 2020 DO - https://doi.org/10.1039/d0nr02159h SP - 1 EP - 12 PB - The Royal Society of Chemistry AN - OPUS4-50978 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Pauli, Jutta A1 - Hoffmann, Katrin 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 - JOUR A1 - Pleskunov, P. A1 - Nikitin, D. A1 - Tafiichuk, R. A1 - Shlemin, A. A1 - Hanus, J. A1 - Kousal, J. A1 - Krtous, Z. A1 - Khalakhan, I. A1 - Kus, P. A1 - Nasu, T. A1 - Nagahama, T. A1 - Funaki, C. A1 - Sato, H. A1 - Gawek, Marcel A1 - Schönhals, Andreas A1 - Choukourov, A. T1 - Plasma polymerization of acrylic acid for the tunable synthesis of glassy abd carboxylated nanoparticle N2 - Polymer nanoparticles (NPs) can be highly attractive in numerous applications including biomedicine where the use of inorganic matter may be detrimental for living tissues. In conventional wet chemistry, polymerization and functionalization of NPs with specific chemical groups involves complex and often numerous reactions. Here, we report on a solvent-free, single-step, low temperature plasma-based synthesis of carboxylated NPs produced by polymerization of acrylic acid under the conditions of a glow discharge. In a monomer-deficient regime, strong fragmentation of the monomer molecules by electron impact results in the formation of 15 nm-sized NPs with <1% retention of the carboxyl groups. In an energy-deficient regime, larger 90 nm-sized NPs are formed with better retention of the carboxyls that reaches 16 %. All types of the NPs exhibit the glass transition above the room temperature which makes them highly stable under aqueous environment with no dissolution or swelling. They are also found to degrade thermally when heated above 150 °C with a decrease of the mean NP size, yet with the retention of the chemical composition. Thus, plasma polymerization proves to be a versatile approach for the production of polymer NPs with tuneable size distribution, chemical composition and physical properties. KW - Nanoparticles PY - 2020 DO - https://doi.org/10.1021/acs.jpcb.9b08960 VL - 124 SP - 668 EP - 678 PB - ACS AN - OPUS4-50351 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Marc Benjamin T1 - Setup of a Particle Scattering Simulation environment N2 - A step by step introduction to the setup of a particle scattering simulation is given. Followed by an installation session. T2 - Seminar of the bioanalysis group CY - Universidad Nacional de Colombia, Medellin, Columbia DA - 12.02.2020 KW - Geant4 KW - Geant4-DNA KW - MCS KW - Monte-Carlo simulations KW - Particle scattering simulations KW - Scattering KW - Simulations KW - Debian KW - Linux KW - Topas KW - C++ KW - Topas-nbio KW - Git KW - Cmake PY - 2020 AN - OPUS4-50366 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gollwitzer, C. A1 - Marguet, S. A1 - Maurino, V. A1 - Hodoroaba, Vasile-Dan T1 - Computation of scattering curves for particles with arbitrary shapes using Debye’s formula N2 - Small-angle scattering data from particle dispersions with narrow size distributions are usually analysed by fitting a model function to the data, which is composed of a monodisperse form factor with a size distribution and, optionally, a structure factor. For common particle shapes like solid spheres, core-shell particles, ellipsoids or rods, the form factor can be computed analytically, and several software packages are readily available which provide a compilation of form factors.1,2 Recently, highly monodisperse nanoparticles with a variety of shapes have been synthesized, e.g. cubes and bipyramids3,4 with lightly capped edges, for which analytic form factors are harder to derive. We compute an approximation to the scattering curve of arbitrary shapes by filling the shape with a quasi-random distribution of point scatterers and using Debye’s formula to get the overall scattering curve. The highly optimized debyer code is used to perform an efficient evaluation of Debye’s formula,5 which can perform the evaluation of 500,000 point scatterers in two minutes on commodity hardware. Moderate polydispersity is handled by interpolating the computed scattering curve over q from a master curve. In this way, the code is fast enough to perform data fitting of particle ensembles with moderate polydispersity for arbitrary shapes to experimental data. This work was partly funded by the 17NRM04 nPSize project of the EMPIR programme co-financed by the EMPIR participating states and by the European Union’s Horizon 2020 research and innovation programme. T2 - 17th Nordic Workshop on Scattering from Soft Matter CY - Linköping, Sweden DA - 14.01.2020 KW - X-ray scattering KW - Nanoparticles KW - Particle shape KW - Modelling KW - Form factor PY - 2020 UR - http://nssm2020.se/ AN - OPUS4-50368 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mech, A. A1 - Rauscher, H. A1 - Babick, F. A1 - Hodoroaba, Vasile-Dan A1 - Wohlleben, W. A1 - Marvin, H. A1 - Weigel, S. A1 - Brüngel, R. A1 - Friedrich, C. M. T1 - The NanoDefine Methods Manual - Part 1: The NanoDefiner Framework and Tools N2 - The present series of reports, the NanoDefine Methods Manual, has been developed within the NanoDefine project 'Development of an integrated approach based on validated and standardized methods to support the implementation of the EC recommendation for a definition of nanomaterial', funded by the European Union's 7th Framework Programme, under grant agreement 604347. In 2011 the European Commission (EC) published a recommendation for a definition of the term 'nanomaterial', the EC NM Definition, as a reference to determine whether an unknown material can be considered as a 'nanomaterial' for regulatory purposes1. One challenge is the development of methods that reliably identify, characterize and quantify nanomaterials (NM) both as substances and in various products and matrices. The overall goal of NanoDefine was to support the implementation of the EC NM Definition. It can also support the implementation of any NM definition based on particle size. The project has developed an integrated approach, which allows identifying any material as a nano- or not a nanomaterial according to the EC NM Definition. NanoDefine explicitly supported the governance challenges associated with the implementation of legislation concerning nanomaterials by: - addressing the issues on availability of suitable measuring techniques, reference materials, validated methods, acceptable to all stakeholders (authorities, policy makers, commercial firms), - developing an integrated and interdisciplinary approach and a close international co-operation and networking with academia, commercial firms and standardization bodies. Thus, the NanoDefine Methods Manual provides guidance on practical implementation of the EC NM Definition throughout the nanomaterial characterization process, and on the characterization techniques employed as well as their application range and limits. It assists the user in choosing the most appropriate measurement method(s) to identify any substance or mixture for a specific purpose, according to the EC NM Definition of a nanomaterial. The NanoDefine project also explored how to assess a material against the criteria of the definition through proxy solutions, i.e. by applying measurement techniques that indirectly determine the x50. Those findings were developed through empirically based scientific work and are included in Part 1 of this Manual. As they go beyond the text of the EC NM Definition, they may be used as practical approach to indicate whether a material is a nanomaterial or not, but keeping in mind that they should not be taken as recommendation for the implementation of the EC NM Definition in a regulatory context. The NanoDefine Methods Manual consists of the following three parts:  Part 1: The NanoDefiner Framework and Tools  Part 2: Evaluation of Methods  Part 3: Standard Operating Procedures (SOPs) Part 1 covers the NanoDefiner framework, general information on measurement methods and performance criteria and tools developed by NanoDefine such as a materials categorisation system, a decision support flow scheme and an e-tool. Part 2 discusses the outcome of the evaluation of the nanomaterials characterisation methods for measuring size. Part 3 presents the 23 Standard Operating Procedures developed within the NanoDefine project. The current document is part 1. KW - Nanomaterial KW - Nanoparticles KW - NanoDefine KW - Nanoparticle size distribution KW - Nanomaterial classification KW - Framework KW - Tools PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-503699 SN - 978-92-76-11950-0 DO - https://doi.org/10.2760/55181 SN - 1831-9424 SP - 1 EP - 89 PB - Publications Office of the European Union CY - Luxembourg AN - OPUS4-50369 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mech, A. A1 - Rauscher, H. A1 - Rasmussen, K. A1 - Babick, F. A1 - Hodoroaba, Vasile-Dan A1 - Ghanem, A. A1 - Wohlleben, W. A1 - Marvin, H. A1 - Brüngel, R. A1 - Friedrich, C. M. T1 - The NanoDefine Methods Manual - Part 2: Evaluation of methods N2 - The present series of reports, the NanoDefine Methods Manual, has been developed within the NanoDefine project 'Development of an integrated approach based on validated and standardized methods to support the implementation of the EC recommendation for a definition of nanomaterial', funded by the European Union's 7th Framework Programme, under grant agreement 604347. In 2011 the European Commission (EC) published a recommendation for a definition of the term 'nanomaterial', the EC NM Definition, as a reference to determine whether an unknown material can be considered as a 'nanomaterial' for regulatory purposes1. One challenge is the development of methods that reliably identify, characterize and quantify nanomaterials (NM) both as substances and in various products and matrices. The overall goal of NanoDefine was to support the implementation of the EC NM Definition. It can also support the implementation of any NM definition based on particle size. The project has developed an integrated approach, which allows identifying any material as a nano- or not a nanomaterial according to the EC NM Definition. NanoDefine explicitly supported the governance challenges associated with the implementation of legislation concerning nanomaterials by: - addressing the issues on availability of suitable measuring techniques, reference materials, validated methods, acceptable to all stakeholders (authorities, policy makers, commercial firms), - developing an integrated and interdisciplinary approach and a close international co-operation and networking with academia, commercial firms and standardization bodies. Thus, the NanoDefine Methods Manual provides guidance on practical implementation of the EC NM Definition throughout the nanomaterial characterization process, and on the characterization techniques employed as well as their application range and limits. It assists the user in choosing the most appropriate measurement method(s) to identify any substance or mixture for a specific purpose, according to the EC NM Definition of a nanomaterial. The NanoDefine project also explored how to assess a material against the criteria of the definition through proxy solutions, i.e. by applying measurement techniques that indirectly determine the x50. Those findings were developed through empirically based scientific work and are included in Part 1 of this Manual. As they go beyond the text of the EC NM Definition, they may be used as practical approach to indicate whether a material is a nanomaterial or not, but keeping in mind that they should not be taken as recommendation for the implementation of the EC NM Definition in a regulatory context. The NanoDefine Methods Manual consists of the following three parts:  Part 1: The NanoDefiner Framework and Tools  Part 2: Evaluation of Methods  Part 3: Standard Operating Procedures (SOPs) Part 1 covers the NanoDefiner framework, general information on measurement methods and performance criteria and tools developed by NanoDefine such as a materials categorisation system, a decision support flow scheme and an e-tool. Part 2 discusses the outcome of the evaluation of the nanomaterials characterisation methods for measuring size. Part 3 presents the 23 Standard Operating Procedures developed within the NanoDefine project. The current document is part 2. KW - Nanomaterial KW - Nanoparticles KW - NanoDefine KW - Particle size distribution KW - Nanomaterial classification PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-503708 SN - 978-92-76-11953-1 DO - https://doi.org/10.2760/071877 SN - 1831-9424 VL - JRC117501 SP - 1 EP - 133 PB - Publications Office of the European Union CY - Luxembourg AN - OPUS4-50370 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mech, A. A1 - Rauscher, H. A1 - Rasmussen, K. A1 - Babick, F. A1 - Hodoroaba, Vasile-Dan A1 - Ghanem, A. A1 - Wohlleben, W. A1 - Marvin, H. A1 - Brüngel, R. A1 - Friedrich, C. M. A1 - Löschner, K. A1 - Gilliland, D. T1 - The NanoDefine Methods Manual - Part 3: Standard Operating Procedures (SOPs) N2 - The present series of reports, the NanoDefine Methods Manual, has been developed within the NanoDefine project 'Development of an integrated approach based on validated and standardized methods to support the implementation of the EC recommendation for a definition of nanomaterial'1 funded by the European Union's 7th Framework Programme, under grant agreement 604347. In 2011 the European Commission (EC) published the recommendation (2011/696/EU) for a definition of the term 'nanomaterial'1, the EC NM Definition, as a reference to determine whether an unknown material can be considered as a 'nanomaterial' for regulatory purposes. One challenge is the development of methods that reliably identify, characterize and quantify nanomaterials (NM) both as substances and in various products and matrices. The overall goal of NanoDefine was to support the implementation of the EC NM Definition. It can also support the implementation of any NM definition based on particle size. The project has developed an integrated approach, which allows identifying any material as a nano or non-nano material according to the EC NM Definition. NanoDefine explicitly supported the governance challenges associated with the implementation of legislation concerning nanomaterials by: - addressing the issues on availability of suitable measuring techniques, reference materials, validated methods, acceptable to all - developing an integrated and interdisciplinary approach and a close international co-operation and networking with academia, commercial firms and standardization bodies. Thus, the NanoDefine Methods Manual provides guidance on practical implementation of the EC NM Definition throughout the nanomaterial characterization process, and on the characterization techniques employed as well as their application range and limits. It assists the user in choosing the most appropriate measurement method(s) to identify any substance or mixture for a specific purpose, according to the EC NM Definition of a nanomaterial. The NanoDefine project also explored how to assess a material against the criteria of the definition through proxy solutions, i.e. by applying measurement techniques that indirectly determine the D50. Those findings were developed through empirically based scientific work and are included in Part 1 of this Manual. As they go beyond the text of the EC NM Definition, they may be used as practical approach to indicate whether a material is a nanomaterial or not, but keeping in mind that they should not be taken as recommendation for the implementation of the EC NM Definition in a regulatory context. The NanoDefine Methods Manual consists of the following three parts:  Part 1: The NanoDefiner Framework and Tools  Part 2: Evaluation of Methods  Part 3: Standard Operating Procedures (SOPs) Part 1 covers the NanoDefiner framework, general information on measurement methods and performance criteria and tools developed by NanoDefine such as a materials categorisation system, a decision support flow scheme and an e-tool. Part 2 discusses the outcome of the evaluation of the nanomaterials characterisation methods for measuring size. Part 3 presents the 23 Standard Operating Procedures developed within the NanoDefine project. The current document is part 3. KW - Nanomaterial KW - Nanoparticles KW - Particle size distribution KW - NanoDefine KW - Standard Operation Procedures KW - Nanomaterial classification KW - SOP PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-503710 SN - 978-92-76-11955-5 DO - https://doi.org/10.2760/02910 SN - 1831-9424 VL - JRC117501 SP - 1 EP - 215 PB - Publications Office of the European Union CY - Luxembourg AN - OPUS4-50371 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Sebastian A1 - Cappella, Brunero T1 - Study of micro- and nanoscale wetting properties of lubricants using AFM force-distance curves N2 - Atomic force microscopy (AFM) plays an important role as a multifuntional tool in nanotribology.In the present work it was shown that the main features of force-distance curves on different lubricants have been characterized and the underlying phenomena could be explained. KW - Lubricants KW - Atomic force microscopy KW - Force-distance curves PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-504631 DO - https://doi.org/10.1007/s11249-020-1275-3 SN - 1573-2711 VL - 68 IS - 1 SP - 1 EP - 12 PB - Springer CY - Cham AN - OPUS4-50463 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Esmann, M. A1 - Chimeh, A. A1 - Korte, A. A1 - Zhong, J. A1 - Stephan, S. A1 - Witt, Julia A1 - Wittstock, G. A1 - Talebi, N. A1 - Lienau, C. T1 - Plasmonic nanofocusing spectral interferometry N2 - We describe and demonstrate a novel experimental approach to measure broadband, amplitude- and phase-resolved scattering spectra of single nanoparticles with 10-nm spatial resolution. Nanofocusing of Surface plasmon polaritons (SPPs) propagating along the shaft of a conical gold taper is used to create a spatially isolated, spectrally broad nanoscale light source at ist very apex. The interference between these incident SPPs and SPPs that are backpropagating from the apex leads to the formation of an inherently phase-stable interferogram, which we detect in the far field by partially scattering SPPs off a small protrusion on the taper shaft. We show that these interferograms allow the reconstruction of both the amplitude and phase of the local optical near fields around individual nanoparticles optically coupled to the taper apex. We extract local light scattering spectra of particles and quantify line broadenings and spectral shifts induced by tip-sample coupling. Our experimental findings are supported by corresponding finite-difference time-domain and coupled dipole simulations and Show that, in the limit of weak tip-sample coupling, the measurements directly probe the projected local density of optical states of the plasmonic system. The combination of a highly stable inline interferometer with the inherent optical background suppression through nanofocusing makes it a promising tool for the locally resolved study of the spectral and temporal optical response of coupled hybrid nanosystems. KW - Plasmonic nanofocusing KW - Near-field spectroscopy PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-504985 DO - https://doi.org/10.1515/nanoph-2019-0397 VL - 9 IS - 2 SP - 491 EP - 508 PB - De Gruyter AN - OPUS4-50498 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geißler, Daniel A1 - Resch-Genger, Ute 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 - Geißler, Daniel A1 - Nirmalananthan-Budau, Nithiya A1 - Resch-Genger, Ute T1 - Preparation and characterization of reference particles for the calibration of flow cytometry for the detection of extracellular vesicles within the EMPIR project MetVes II N2 - Extracellular vesicles (EV) are cell-derived particles in body fluids, which have excellent potential as next-generation biomarkers. The exploitation of EV requires reliable measurements, which is currently very difficult, as most EV are smaller than 200 nm. At present, flow cytometry (FCM) is the most appropriate technique for EV analysis in biological samples, as FCM is readily available in many clinical laboratories and allows to identify cell-specific EV at high throughput. However, due to technical variations between different FCM instruments, EV concentration measurements are currently not well comparable between most laboratories. Therefore, EV reference materials and standardized reference methods are urgently needed to calibrate flow rate, light scattering intensity, and fluorescence intensity of FCM in the sub-micrometer size range. This requires a better matching of the optical properties of calibration beads and EV as can be realized with current polystyrene calibration beads. The EMPIR project 18HLT01 “MetVes II” aims to develop synthetic reference materials and traceable measurement methods to standardize EV measurements. The reference materials should resemble EV properties, so that calibrations are reliable and do not require a change of acquisition settings. Hence, the reference materials should contain particles with a traceable number concentration in the range of 109–1012 particles/mL to calibrate flow rate, a traceable size with discrete diameters between 50–1000 nm and a refractive index (RI) in the range of 1.37–1.42 to calibrate scattering intensity, and a traceable fluorescence intensity between 100–100,000 molecules of equivalent soluble fluorochromes (MESF). At BAM, various approaches to prepare such low-RI nanometer-sized reference materials will be studied, preliminary results of the primary characterization of these candidate reference particles will be presented, and possible applications besides FCM-based EV detection will be outlined. T2 - 29th Meeting of the German Society for Cytometry (DGfZ) CY - Berlin, Germany DA - 25.09.2019 KW - Extracellular vesicles (EV) KW - Flow cytometry KW - Reference particles KW - EMPIR project KW - 18HLT01 MetVes II PY - 2019 AN - OPUS4-50394 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liebig, F. A1 - Sarhan, R. M. A1 - Schmitt, C. N. Z. A1 - Thünemann, Andreas A1 - Prietzel, C. A1 - Bargheer, M. A1 - Koetz, J. T1 - Gold Nanotriangles with Crumble Topping and their Influence on Catalysis and Surface‐Enhanced Raman Spectroscopy N2 - By adding hyaluronic acid (HA) to dioctyl sodium sulfosuccinate (AOT)‐stabilized gold nanotriangles (AuNTs) with an average thickness of 7.5±1 nm and an edge length of about 175±17 nm, the AOT bilayer is replaced by a polymeric HA‐layer leading to biocompatible nanoplatelets. The subsequent reduction process of tetrachloroauric acid in the HA‐shell surrounding the AuNTs leads to the formation of spherical gold nanoparticles on the platelet surface. With increasing tetrachloroauric acid concentration, the decoration with gold nanoparticles can be tuned. SAXS measurements reveal an increase of the platelet thickness up to around 14.5 nm, twice the initial value of bare AuNTs. HRTEM micrographs show welding phenomena between densely packed particles on the platelet surface, leading to a crumble formation while preserving the original crystal structure. Crumbles crystallized on top of the platelets enhance the Raman signal by a factor of around 20, and intensify the plasmon‐driven dimerization of 4‐nitrothiophenol (4‐NTP) to 4,4′‐dimercaptoazobenzene in a yield of up to 50 %. The resulting crumbled nanotriangles, with a biopolymer shell and the absorption maximum in the second window for in vivo imaging, are promising candidates for biomedical sensing. KW - SAXS KW - Small-angle X-ray scattering KW - Nanoparticle KW - Gold PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-503977 DO - https://doi.org/10.1002/cplu.201900745 VL - 85 IS - 3 SP - 519 EP - 526 PB - Wiley-VCH Verlag CY - Weinheim AN - OPUS4-50397 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Marc Benjamin A1 - Zutta Villate, J. M. T1 - Ejemplos de simulaciónes de Montecarlo La desintegración radioactiva N2 - A walkthrough how to setup radioactive sources in monte-carlo particle scattering simulations and perform different types of scorings. N2 - En esta presentación desarrollaremos un ejemplo de aplicación para la dispersión de partículas utilizando el método de simulación de Monte- Carlo. Se discutirá el caso de las nanopartículas de oro radiactivo y los diferentes tipos del scoring. T2 - Seminar of the bioanalysis group CY - Universidad Nacional de Colombia, Medellin, Columbia DA - 27.02.2020 KW - MCS KW - Geant4-DNA KW - Geant4 KW - Radioactive nanoparticle KW - Radioactive decay KW - Particle scattering simulations KW - Particle scattering simulation KW - Topas KW - Monte-Carlo simulations KW - Desintegracion radioactiva KW - Método de Montecarlo KW - Geant4 KW - nanoparticula PY - 2020 AN - OPUS4-50472 LA - spa AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ulbricht, Alexander A1 - Léonard, Fabien A1 - Evsevleev, Sergei A1 - Kupsch, Andreas A1 - Müller, Bernd R. A1 - Bruno, Giovanni T1 - To see and not to see - Möglichkeiten und Grenzen der Schadensanalyse mit CT an Kompositmaterialien N2 - Anhand von drei Beispielen (Datenfusion an CFK; Machine Learning an Metall-Matrix-Kompositen sowie Refraktion an CFK) wird gezeigt, wie die BAM mit neuen Analysemethoden mehr Informationen aus CT-Datensätzen extrahieren kann, sowie mit der Refraktion eine Analysemethode besitzt, die in Fällen eingesetzt werden kann, bei denen klassische Durchstrahlungsmethoden kein Ergebnis liefern. T2 - InnoTesting 2020 CY - Wildau, Germany DA - 27.02.2020 KW - Computed tomography KW - Computertomographie KW - Röntgenrefraktion KW - Machine Learning KW - Datenfusion KW - Data Fusion KW - Synchrotron PY - 2020 AN - OPUS4-50485 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Campbell, C. G. A1 - Jordon Astorga, D. A1 - Dümichen, Erik A1 - Celina, M. T1 - Thermoset materials characterization by thermal desorption or pyrolysis based gas chromatography-mass spectrometry methods N2 - Thermoset materials characterization is often limited to solid state analytical techniques such as IR, NMR, DSC, TGA and mechanical testing. Alternatively, their off-gassing behavior can also be evaluated using GC based techniques such as TD-GC-MS, allowing this method to be applied to thermoset materials analyses such as identification, aging characterization, and formulation optimization. As an overview, common thermoset materials were evaluated by analyzing their gaseous degradation products via TGA-based pyrolysis and subsequent TD-GC-MS for the identification of representative volatile signatures. It is thereby possible to distinguish different classes of phenolic materials or cured epoxy resins, as well as their amine or anhydride curatives. Additionally, this method enabled quantification of a volatile fragment (bisphenol A, BPA) which is associated with oxidation of epoxy/amine thermoset materials. The amount of evolved BPA increased linearly with aging time and this trend exhibits linear Arrhenius behavior over the temperature range (80–125 °C) studied, in agreement with oxidation sensitivies based on oxygen consumption data. Further, TD-GC-MS was used to explore how off-gassing of residual anhydride curative from an epoxy/anhydride material depends on formulation stoichiometry. Even in formulations that theoretically contained enough epoxy to consume all anhydride (1:1 stoichiometry), an imperfect final cure state resulted in residual anhydride which could evolve from the material. For such materials, a slightly epoxy-rich formulation is required to ensure that the material contains no residual unreacted anhydride. Analysis of volatiles generated by thermal exposure is an attractive characterization approach enabling compositional analysis as well as complementary diagnostics for materials degradation. KW - Polymer analysis/characterization KW - Thermal desorption mass spectrometry KW - Thermoset composition KW - Volatiles from thermosets KW - Degradation signatures PY - 2020 DO - https://doi.org/10.1016/j.polymdegradstab.2019.109032 VL - 174 SP - 109032 PB - Elsevier Ltd. AN - OPUS4-50435 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Marcoulaki, E. A1 - van Duuren, B A1 - Kunz, Valentin A1 - Unger, Wolfgang A1 - Shandilya, N. T1 - Testing and benchmarking nanosafety services N2 - One of the objectives of the EU Project EC4SafeNano (European Centre for Risk Management and Safe Innovation in Nanomaterials & Nanotechnologies) was to test and benchmark the services in order to check their relevance to address identified stakeholder needs, but also to evaluate the governance of the structure delivering the proposed services. The aim is to demonstrate the technical relevance of the services and the overall open structure organisation, including governance rules and operating procedures, by answering relevant identified questions (case studies) selected by a panel of stakeholders. Therefore, a significant part of the project will be devoted to this demonstration of the operational and functional basis of the organized network. T2 - Review Meeting EC4SafeNano CY - Brussels, Belgium DA - 16.01.2020 KW - Nanosafety KW - EC4SafeNano KW - Nanosafety services KW - EU KW - Case studies PY - 2020 AN - OPUS4-50273 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kembuan, C. A1 - Saleh, Maysoon I. A1 - Rühle, Bastian A1 - Resch-Genger, Ute A1 - Graf, C. T1 - Coating of upconversion nanoparticles with silica nanoshells of 5–250 nm thickness N2 - A concept for the growth of silica shells with a thickness of 5–250 nm onto oleate-coated NaYF4:Yb3+/Er3+ upconversion nanoparticles (UCNP) is presented. The concept enables the precise adjustment of shell thicknesses for the preparation of thick-shelled nanoparticles for applications in plasmonics and sensing. First, an initial 5–11 nm thick shell is grown onto the UCNPs in a reverse microemulsion. This is followed by a stepwise growth of these particles without a purification step, where in each step equal volumes of tetraethyl orthosilicate and ammonia water are added, while the volumes of cyclohexane and the surfactant Igepal® CO-520 are increased so that the ammonia water and surfactant concentrations remain constant. Hence, the number of micelles stays constant, and their size is increased to accommodate the growing core–shell particles. Consequently, the formation of core-free silica particles is suppressed. When the negative zeta potential of the particles, which continuously decreased during the stepwise growth, falls below −40 mV, the particles can be dispersed in an ammoniacal ethanol solution and grown further by the continuous addition of tetraethyl orthosilicate to a diameter larger than 500 nm. Due to the high colloidal stability, a coalescence of the particles can be suppressed, and single-core particles are obtained. This strategy can be easily transferred to other nanomaterials for the design of plasmonic nanoconstructs and sensor systems. KW - Reverse microemulsion KW - Silica coating KW - Stepwise growth KW - Thick shells KW - Upconversion nanoparticles PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-502769 DO - https://doi.org/10.3762/bjnano.10.231 SN - 2190-4286 VL - 10 SP - 2410 EP - 2421 PB - Beilstein-Institut zur Förderung der Chemischen Wissenschaften CY - Frankfurt, M. AN - OPUS4-50276 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Nanopatterned and Nanoparticle‐Modified Electrodes N2 - Since nanoscience has a tremendous impact on the development of electrochemistry, Wiley‐VCH paid attention to that by publishing thisbook as volume 17 within the series “Advances in Electrochemical Science and Engineering”. This collection of “nanoaspects”on electrodes provides a helpful overview on principles and current findings to readers interested in such applications. It fulfills its intention of being “a valuable resource for researchers working in such fields as electrochemistry, materials science, spectroscopy, analytical and medicinal chemistry”. KW - Electrochemistry KW - Nanoparticle PY - 2020 DO - https://doi.org/10.1002/maco.202070014 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 1 SP - 179 EP - 180 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50205 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kool, L. A1 - Dekker, F. A1 - Bunschoten, A. A1 - Smales, Glen Jacob A1 - Pauw, Brian Richard A1 - Velders, A. H. A1 - Saggiomo, V. T1 - Gold and silver dichroic nanocomposite in the quest for 3D printing the Lycurgus cup N2 - The Lycurgus cup is an ancient glass artefact that shows dichroism as it looks green when a white light is reflected on it and a red colouring appears when a white light is transmitted through it. This peculiar dichroic effect is due to silver and gold nanoparticles present in the glass. In this research we show the synthesis of dichroic silver nanoparticles and their embedding in a 3D printable nanocomposite. The addition of gold nanoparticles to the silver nanoparticle composite, gave a 3D printable nanocomposite with the same dichroism effect of the Lycurgus cup. KW - SAXS KW - Au KW - Ag KW - Nanocomposite KW - 3D printing PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-501831 DO - https://doi.org/10.3762/bjnano.11.2 SP - 16 EP - 23 AN - OPUS4-50183 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Friedrich, C. M. A1 - Weigel, S. A1 - Marvin, H. A1 - Rauscher, H. A1 - Wohlleben, W. A1 - Babick, F. A1 - Löschner, K. A1 - Mech, A. A1 - Brüngel, R. A1 - Hodoroaba, Vasile-Dan A1 - Gilliland, D. A1 - Rasmussen, K. A1 - Ghanem, A. T1 - The NanoDefine Methods Manual N2 - This document is a collection of three JRC Technical Reports that together form the “NanoDefine Methods Manual”, which has been developed within the NanoDefine project ‘Development of an integrated approach based on validated and standardized methods to support the implementation of the EC recommendation for a definition of nanomaterial’, funded by the European Union’s 7th Framework Programme, under grant agreement 604347. The overall goal of the NanoDefine project was to support the implementation of the European Commission Recommendation on the definition of nanomaterial (2011/696/EU). The project has developed an integrated empirical approach, which allows identifying a material as a nano- or not a nanomaterial according to the EC Recommendation. The NanoDefine Methods Manual consists of three parts: Part 1: The NanoDefiner Framework and Tools, which covers the NanoDefiner framework, general information on measurement methods and performance criteria, and tools developed by NanoDefine such as a materials categorisation system, a decision support flow scheme and an e-tool. Part 2: Evaluation of Methods, which discusses the outcome of the evaluation of the nanomaterials characterisation methods for measuring size. Part 3: Standard Operating Procedures (SOPs), which presents the 23 Standard Operating Procedures developed within the NanoDefine project. In this combined document, these three parts are included as stand-alone reports, each having its own abstract, table of contents, page, table and figure numbering, and references. KW - Nanomaterial KW - Particle size distribution KW - Nanoparticles KW - NanoDefine KW - Nanomaterial classification PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-504250 SN - 978-92-76-12335-4 DO - https://doi.org/10.2760/79490 VL - JRC117501 SP - 1 EP - 451 PB - Publications Office of the European Union CY - Luxembourg AN - OPUS4-50425 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Wolfgang T1 - International standardization and metrology as tools to address the comparability and reproducibility challenges in XPS measurements N2 - The status of standardization related to x-ray photoelectron spectroscopy (XPS, ESCA) at ASTM International (Subcommittee E42.03) and ISO (TC 201) is presented and commented upon in a structured manner. The survey also identifies other active bodies, here VAMAS Technical Working Area 2 and the Surface Analysis Working Group at the International Meter Convention, contributing to prestandardization Research and metrology of XPS and reports their specific activities. It is concluded that existing standardization is delivering good practices in the use of XPS and has a high potential to avoid the recently observed erroneous use, misapplications, and misinterpretation by new and inexperienced users of the method—which seems to be the main reason for the “reproducibility crisis” in the field of XPS applications. A need for a more proactive publicizing of international documentary standards by experienced XPS users, specifically those who are involved in standardization, is identified. Because the existing portfolio of standards addressing the use of XPS is not complete, future standardization projects planned or already ongoing are mentioned. The way the standardization bodies are identifying future needs is shortly explained. KW - Standardisation KW - Comparability KW - Reproducibility KW - XPS KW - VAMAS KW - Metrology PY - 2020 DO - https://doi.org/10.1116/1.5131074 VL - 38 IS - 2 SP - 021201-1 EP - 021201-8 PB - AVS AN - OPUS4-50560 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Spaltmann, Dirk T1 - Editorial: Special issue "Laser-induced periodic surface nano- and microstructures for tribological applications" N2 - Laser material processing is an emerging technology that generates surface functionalities on the basis of optical, mechanical, or chemical properties. In the form of laser surface texturing (LST), it has attracted a remarkable amount of research to tailor surface properties towards various tribological applications. The main advantages of this single-step, laser-based technology are the contactless machining, featuring a high flexibility, efficiency, and speed, along with the excellent quality of the processed products. LST can be applied precisely localized to sub-micrometric areas, but, via laser beam scanning, it is also feasible for structuring large surface areas at the square meter size. This Special Issue focuses on the latest developments concerning the tribological performance of laser-generated periodic surface nano- and microstructures and their applications. This includes the laser-based processing of different surface patterns, such as “self-organized” laser-induced periodic surface structures (LIPSS, ripples), grooves, micro-spikes, hierarchical hybrid nano-/micro-structures, microfeatures generated by direct laser interference patterning (DLIP), or even dimples or other topographic geometries shaped by direct laser modification or ablation. The applications of these periodically nano- and micro-patterned surfaces may improve the lubricated or non-lubricated tribological performance of surfaces in conformal and even non-conformal contact through a reduction of wear, a variation of the coefficient of friction, altered load carrying capacity, etc., resulting in energy saving, improved reliability, increased lifetimes as well as durability, leading in turn to extended maintenance intervals/reduced down-time. This can be beneficial in terms of bearings, gears, engines, seals, cutting tools, or other tribological components. Fundamental aspects addressed may involve the investigation of the relevant physical and chemical effects accompanying the laser-generated nano- and microscale topographies, such as alterations of the material structures, the hardness, superficial oxidation, the role of additives contained in lubricants, surface wettability, micro-hydrodynamic effects, etc. For this Special Issue we aim to attract both academic and industrial researchers and would like to provide a bridge between research in the fields of tribology and laser material processing in order to foster the current knowledge and present new ideas for future applications and new technologies. KW - Laser-induced periodic surface structures (LIPSS) KW - Tribology KW - Applications KW - Wear KW - Friction PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-505948 DO - https://doi.org/10.3390/lubricants8030034 SN - 2075-4442 VL - 8 IS - 3 SP - 34, 1 EP - 34, 3 PB - MDPI CY - Basel AN - OPUS4-50594 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bennet, Francesca A1 - Hodoroaba, Vasile-Dan A1 - Burr, L. A1 - Schmid, D. T1 - Microprinting and SEM analysis for quantitative evaluation of nanoparticles in solution N2 - Nanoparticle suspensions were microprinted onto TEM grids for subsequent analysis by SEM/TSEM and evaluation of particle numbers using Image J software. Various nanoparticle types, concentrations and printing conditions (temperature, rel. humidity) were evaluated in order to determine the optimal conditions for producing a uniform distribution of particles on the substrate and eliminating the coffee ring effect. T2 - H2020 ACEnano Project Meeting CY - Amsterdam, Netherlands DA - 04.03.2020 KW - Nanoparticle KW - Imaging KW - Microprinting KW - Homogeneous deposition PY - 2020 AN - OPUS4-50584 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Marc Benjamin T1 - Simulaciónes de Montecarlo II: El scoring en las superficies N2 - En esta presentación desarrollaremos un ejemplo de aplicación para la dispersión de partículas utilizando el método de simulación de Monte- Carlo. Se discutirá el caso de las nanopartículas de oro radiactivo y como obtener informacions sobre diferente tipos de particulas pasando las superfices. T2 - Seminar of the bioanalysis group CY - Universidad Nacional de Colombia, Medellin, Colombia DA - 16.03.2020 KW - Geant4 KW - Geant4-DNA KW - MCS KW - Particle scattering simulation KW - Particle scattering simulations KW - Radioactive decay KW - Radioactive nanoparticle KW - Desintegracion radioactiva KW - Geant4 KW - Monte-Carlo simulations KW - Método de Montecarlo KW - Topas KW - nanoparticula PY - 2020 AN - OPUS4-50564 LA - spa AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg T1 - Minimale Anforderungen an Referenzdaten anhand von Beispielen aus der Elektronenmikroskopie und Oberflächenanalytik N2 - In dem Vortrag werden, anhand ausgewählten Beispielen aus der Elektronenmikroskopie und Oberflächenanalytik (EDX und XPS), die minimalen Anforderungen an Referenzdaten für zuverlässige und reproduzierbare Ergebnisse (z.B. Partikelgrößenverteilung, Elementzusammensetzung) vorgestellt und diskutiert. T2 - Workshop "Referenzdaten" CY - Berlin, Germany DA - 13.03.2020 KW - Referenzdaten KW - Nanopartikel KW - Elektronenmikroskopie KW - Oberflächenanalytik KW - Standardarbeitsanweisung KW - SOP KW - Standardisierung PY - 2020 AN - OPUS4-50571 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR ED - Bonse, Jörn ED - Spaltmann, Dirk T1 - Special issue: Laser-induced periodic surface nano- and microstructures for tribological applications N2 - Laser material processing is an emerging technology that generates surface functionalities on the basis of optical, mechanical, or chemical properties. In the form of laser surface texturing (LST), it has attracted a remarkable amount of research to tailor surface properties towards various tribological applications. The main advantages of this single-step, laser-based technology are the contactless machining, featuring a high flexibility, efficiency, and speed, along with the excellent quality of the processed products. LST can be applied precisely localized to sub-micrometric areas, but, via laser beam scanning, it is also feasible for structuring large surface areas at the square meter size. This Special Issue focuses on the latest developments concerning the tribological performance of laser-generated periodic surface nano- and microstructures and their applications. This includes the laser-based processing of different surface patterns, such as “self-organized” laser-induced periodic surface structures (LIPSS, ripples), grooves, micro-spikes, hierarchical hybrid nano-/micro-structures, microfeatures generated by direct laser interference patterning (DLIP), or even dimples or other topographic geometries shaped by direct laser modification or ablation. The applications of these periodically nano- and micro-patterned surfaces may improve the lubricated or non-lubricated tribological performance of surfaces in conformal and even non-conformal contact through a reduction of wear, a variation of the coefficient of friction, altered load carrying capacity, etc., resulting in energy saving, improved reliability, increased lifetimes as well as durability, leading in turn to extended maintenance intervals/reduced down-time. This can be beneficial in terms of bearings, gears, engines, seals, cutting tools, or other tribological components. Fundamental aspects addressed may involve the investigation of the relevant physical and chemical effects accompanying the laser-generated nano- and microscale topographies, such as alterations of the material structures, the hardness, superficial oxidation, the role of additives contained in lubricants, surface wettability, micro-hydrodynamic effects, etc. For this Special Issue we aim to attract both academic and industrial researchers and would like to provide a bridge between research in the fields of tribology and laser material processing in order to foster the current knowledge and present new ideas for future applications and new technologies. KW - Applications KW - Friction KW - Laser-induced periodic surface structures (LIPSS) KW - Tribology KW - Wear PY - 2020 UR - https://www.mdpi.com/journal/lubricants/special_issues/laser_periodic SN - 2075-4442 VL - 8 IS - 3 SP - Article 1 EP - Article 10 PB - MDPI CY - Basel AN - OPUS4-50914 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Besselink, R. A1 - Stawski, Tomasz A1 - Freeman, H. M. A1 - Hovelmann, J. A1 - Tobler, D. J. A1 - Benning, L. G. T1 - Mechanism of Saponite Crystallization from a Rapidly Formed Amorphous Intermediate N2 - Clays are crucial mineral phases in Earth’s weathering engine, but we do not know how they form in surface environments under (near-)ambient pressures and temperatures. Most synthesis routes, attempting to give insights into the plausible mechanisms, rely on hydrothermal conditions, yet many geological studies showed that clays may actually form at moderate temperatures (<100 °C) in most terrestrial settings. Here, we combined high-energy X-ray diffraction, infrared spectroscopy, and transmission electron microscopy to derive the mechanistic pathways of the low-temperature (25–95 °C) crystallization of a synthetic Mg-clay, saponite. Our results reveal that saponite crystallizes via a two stage process: (1) a rapid (several minutes) coprecipitation where ∼20% of the available magnesium becomes incorporated into an aluminosilicate network, followed by (2) a much slower crystallization mechanism (several hours to days) where the remaining magnesium becomes gradually incorporated into the growing saponite sheet structure. KW - Saponite KW - FTIR KW - PDF KW - Diffraction PY - 2020 DO - https://doi.org/10.1021/acs.cgd.0c00151 VL - 20 IS - 5 SP - 3365 EP - 3373 PB - American Chemical Society AN - OPUS4-50917 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cano Murillo, Natalia A1 - Ghasem Zadeh Khorasani, Media A1 - Silbernagl, Dorothee A1 - Hahn, Marc Benjamin A1 - Hodoroaba, Vasile-Dan A1 - Sturm, Heinz T1 - Nanomechanical study of polycarbonate/boehmite nanoparticles/epoxy ternary composite and their interphases N2 - Thermoplastic modified thermosets are of great interest especially due to their improved fracture toughness. Comparable enhancements have been achieved by adding different nanofillers including inorganic particles such as nanosized boehmite. Here, we present a nanomechanical study of two composite systems, the first comprising a polycarbonate (PC) layer in contact with epoxy resin (EP) and the second consisting of a PC layer containing boehmite nanoparticles (BNP) which is also in contact with an EP layer. The interaction between PC and EP monomer is tested by in situ Fourier transformed infrared (FT-IR) analysis, from which a reaction induced phase separation of the PC phase is inferred. Both systems are explored by atomic force microscopy (AFM) force spectroscopy. AFM force-distance curves (FDC) show no alteration of the mechanical properties of EP at the interface to PC. However, when a PC phase loaded with BNP is put in contact with an epoxy system during curing, a considerable mechanical improvement exceeding the rule of mixture was detected. The trend of BNP to agglomerate preferentially around EP dominated regions and the stiffening effect of BNP on EP shown by spatial resolved measurements of Young's modulus, suggest the effective presence of BNP within the EP phase. KW - Composites KW - Mechanical properties KW - Nanoparticles KW - Thermoplastics KW - Thermosets PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-515965 DO - https://doi.org/10.1002/app.50231 SN - 0021-8995 SN - 1097-4628 VL - 138 IS - 12 SP - 1 EP - 11 PB - Wiley CY - New York, NY AN - OPUS4-51596 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Yamamoto, K. A1 - Grulke, E. A. A1 - Maurino, V. ED - Bosse, H. ED - Buhr, E. ED - Dziomba, T. ED - Hodoroaba, Vasile-Dan ED - Klein, T. ED - Krumrey, M. T1 - Shape controlled TiO2 nanoparticles as candidates for nano-CRM’s – an ISO case study N2 - Extraction of true, 3D shape (and size) of non-spherical nanoparticles (NPs) is associated with Errors by conventional 2D electron microscopy using projection images. Significant efforts within the ISO technical committee TC 229 ‘Nanotechnologies’ are aimed at establishing accurate TEM and SEM measurement of NP size and shape as robust, standard procedures. Study groups have been organizing inter-laboratory comparisons on well-selected NP systems according to the market needs, such as aggregated titania nano-powder for which size and shape distribution of primary crystallites of irregular shape must be measured accurately. To be noticed is e. g. the fact that the measurement procedure allows only manual selection of the particles clearly distinguishable for analysis as well as manual definition of the contour of the imaged NPs. An inter-laboratory exercise on titania NPs (pure anatase, grown by hydrothermal synthesis) of well-defined non-spherical shape, i.e. bipyramidal, has been recently started within ISO/TC 229 under similar conditions as for the irregular shaped titania. In the TEM micrograph the particles tracked manually according to the measurement protocol. Overlapped particles were allowed to be considered, as long as they are clearly distinguishable. One decisive NP selection criterion was to analyze only those NPs with a roundness value below 0.7, i.e. the NPs laying on the support foil and, hence, with projection areas clearly deviating from perfect circles (R=1). The overall evaluation (for 15 labs) of the size descriptors (area, Feret, minFeret, perimeter) and shape descriptors (aspect ratio, roundness, compactness, extent) by analysis of variance is just to be finished and included in ISO/WD 21363 Nanotechnologies -- Protocol for particle size distribution by transmission electron microscopy. T2 - NanoWorkshop 2018: Workshop on Reference Nanomaterials CY - Berlin, Germany DA - 14.05.2018 KW - Titanium dioxide KW - Nanoparticles KW - Shape-controlled KW - Electron microscopy PY - 2019 SN - 978-3-95606-440-1 DO - https://doi.org/https://doi.org/10.7795/110.20190412 SN - 0179-0609 VL - F-61 SP - 245 EP - 255 PB - Physikalisch-Technische Bundesanstalt CY - Braunschweig und Berlin AN - OPUS4-49990 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mech, A. A1 - Gaillard, C. A1 - Marvin, H. A1 - Wohlleben, W. A1 - Hodoroaba, Vasile-Dan A1 - Babick, F. A1 - Friedrich, C. M. A1 - Brüngel, R. A1 - Rückert, J. A1 - Ghanem, A. A1 - Weigel, S. T1 - The NanoDefine Decision Framework and NanoDefiner e-Tool: a practical guide to the identification of nanomaterials N2 - The European Commission's recommendation on the definition of nanomaterial [2011/696/EU] is broadly applicable across different regulatory sectors and requires the quantitative size Determination of constituent particles in samples down to 1 nm. A material is a nanomaterial if 50 % or more of the particles are in the size range 1-100 nm. The implementation of the definition in a regulatory context challenges measurement methods to reliably identify nanomaterials and ideally also nonnanomaterials as substance or product ingredient as well as in various matrices. The EU FP7 NanoDefine project [www.nanodefine.eu] addressed these challenges by developing a robust, readily implementable and cost-effective measurement strategy to decide for the widest possible range of materials whether it is a nanomaterial or not. It is based on existing and emerging particle measurement techniques evaluated against harmonized, material-dependent performance criteria and by intra- and inter-lab comparisons. Procedures were established to reliably measure the size of particles within 1-100 nm, and beyond, taking into account different shapes, coatings and chemical compositions in industrial materials and consumer products. Case studies prove their applicability for various sectors, including food, pigments and cosmetics. A main outcome is the establishment of an integrated tiered approach including rapid screening (Tier 1) and confirmatory methods (tier 2), a decision support flow scheme and a user manual to guide end-users, such as manufacturers, in selecting appropriate methods. Another main product is the “NanoDefiner” e-Tool which implements the flow scheme in a user-friendly software and guides the user in a semi-automated way through the entire decision procedure. It allows a cost-effective selection of appropriate methods for material classification according to the EC's nanomaterial definition and provides a comprehensive report with extensive explanation of all decision steps to arrive at a transparent identification of nanomaterials as well as non-nanomaterials for regulatory purposes. T2 - NanoWorkshop 2018: Workshop on Reference Nanomaterials CY - Berlin, Germany DA - 14.05.2018 KW - Definition of nanomaterial KW - Regulation PY - 2019 SN - 978-3-95606-440-1 SN - 0179-0609 VL - F-61 SP - 114 EP - 124 PB - Physikalisch-Technische Bundesanstalt CY - Braunschweig und Berlin AN - OPUS4-49992 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maurino, V. A1 - Pellutiè, L. A1 - Pellegrino, F. A1 - Ortel, Erik A1 - Hodoroaba, Vasile-Dan A1 - Isopescu, R. T1 - Synthesis of size and shape controlled TiO2 nanoparticles: possible CRM’s candidates for size, shape and functional properties N2 - Titanium dioxide is one of the most studied metal oxides due to its chemical, surface, electronic and (photo)catalytic properties, providing this material of multisectorial applications ranging from healthcare, photocatalysis, smart materials with self cleaning and self sterilizing properties and solar energy harvesting. However it is difficult to correlate the functional properties of TiO2 nanomaterials to the properties at single nanoparticle level due to the high polydispersity in shape, size and surface features of the currently available TiO2 nanoparticles (NPs). Although intensive experimental and theoretical studies have been conducted on the reactivity of different surfaces of metal oxides such as TiO2 much less attention is paid on the dependence of functional properties, like photocatalytic activity, dye adsorption, open circuit potential and fill factor in dye sensitized solar cells, on crystal facets in different orientations. One of the goal of SETNanoMetro project was the development of design rules to tune crystal facets of TiO2 NPs in order to optimize and control functional properties. In the present work we have developed a series of design rules in order to obtain sets of anatase TiO2 NPs with low polydispersity and to tune their shape and size by hydrothermal processing of Ti(IV)- Triethanolamine complex in presence of different shape controllers. Through a careful experimental design, a predictive soft model was developed. The model is able to predict the synthesis outcome allowing to tune the shape factor from 5 (prisms) to 1.5 (bipyramids) to 0.2 (platelets). This allows to control the main crystal facets exposed ranging from (100) to (001). Due to the dependence of functional properties of nanomaterials on shape distribution and not only size, the availability of NPs sets with uniform and well defined and tunable shapes can be of paramount relevance in order to produce reference nanomaterials for shape measurement. T2 - NanoWorkshop 2018: Workshop on Reference Nanomaterials CY - Berlin, Germany DA - 14.05.2018 KW - Anatase KW - shape control KW - Hydrothermal synthesis PY - 2019 SN - 978-3-95606-440-1 SN - 0179-0609 VL - F-61 SP - 146 EP - 162 PB - Physikalisch-Technische Bundesanstalt CY - Braunschweig und Berlin AN - OPUS4-49993 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stock, V. A1 - Fahrenson, C. A1 - Thünemann, Andreas A1 - Donmez, M. H. A1 - Voss, L. A1 - Bohmert, L. A1 - Braeuning, A. A1 - Lampen, A. A1 - Sieg, H. T1 - Impact of artificial digestion on the sizes and shapes of microplastic particles N2 - Current analyses show a widespread occurrence of microplastic particles in food products and raise the question of potential risks to human health. Plastic particles are widely considered to be inert due to their low chemical reactivity and therefore supposed to pose, if at all only minor hazards. However, variable physicochemical conditions during the passage of the gastrointestinal tract gain strong importance, as they may affect particle characteristics. This study aims to analyze the impact of the gastrointestinal passage on the physicochemical particle characteristics of the five most produced and thus environmentally relevant plastic materials polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate and polystyrene. Scanning electron microscopy (SEM) and subsequent image analysis were employed to characterize microplastic particles. Our results demonstrate a high resistance of all plastic particles to the artificial digestive juices. The present results underline that the main stages of the human gastrointestinal tract do not decompose the particles. This allows a direct correlation between the physicochemical particle characteristics before and after digestion. Special attention must be paid to the adsorption of organic compounds like proteins, mucins and lipids on plastic particles since it could lead to misinterpretations of particle sizes and shapes. KW - Artificial digestion KW - Gastrointestinal barrier KW - Microplastic KW - Oral uptake KW - Particle size PY - 2020 DO - https://doi.org/10.1016/j.fct.2019.111010 VL - 135 SP - 111010 PB - Elsevier Ltd. AN - OPUS4-49999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Mansfeld, Ulrich A1 - Hörenz, Christoph A1 - Pellegrino, F. A1 - Maurino, V. A1 - Marguet, S. A1 - Testard, F. A1 - Tache, O. A1 - Bartczak, D. A1 - Goenaga-Infante, H. T1 - Challenges in Traceable Size Measurement of Non-Spherical, Non-Monodisperse Nanoparticles - nPSize N2 - Size measurement of nanoparticles (NP) becomes a challenging analytical problem when non-spherical shapes must be traceably measured. However, most industrial NPs have irregular shapes and broad size distribution making it often more complex to follow European regulatory to identify a material as a nanomaterial according to which accurate measurement of the smallest dimension and its size Distribution is necessary. The European research project nPSize - Improved traceability chain of nanoparticle size measurements aims to fill this gap by developing potential non-spherical reference nanoparticles, measurement procedures and physical modelling to improve the traceability chain, comparability and compatibility for NP size measurements between different methods. Therefore, new model NP with well-controlled shape has been synthesized and are supposed to be systematically characterized using the traceable methods scanning/transmission electron microscopy, atomic force microscopy and small angle X-ray scattering. Following NP candidates are under investigation with respect to their homogeneity and stability: (i) titania nanoplatelets (10-15 nm thickness x 50-100 nm lateral), (ii) titania bipyramides (~60 nm length x 40 nm width), (iii) titania acicular particles (100 nm length x 15-20 nm width; aspect ratio 5.5/6), (iv) gold nanorods (~10 nm width x 30 nm length), and (v) gold nanocubes (~55 nm x 55 nm x 55 nm). In addition, sample preparation procedures as well as measurement analysis procedures with evaluation of appropriate measurands and descriptors for each material class and method are being developed to support standardization. To underpin the traceability of the size measurement of nonspherical NP, physical modelling of the signals in e.g. electron microscopy techniques will be used and in combination, the implementation of machine learning is aimed to facilitate measurement Analysis procedures, especially regarding the accurate thresholding/segmentation of the NPs.zeige mehr T2 - Nanoparticle Reference Materials - Production and Cerification Training Course CY - London, UK DA - 10.12.2019 KW - Nanoparticles KW - Traceability KW - Particle size distribution KW - Electron microscopy KW - Reference materials KW - Non-spherical shape PY - 2019 AN - OPUS4-50040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sentker, K. A1 - Yildirim, Arda A1 - Lippmann, M. A1 - Zantop, A. W. A1 - Bertram, F. A1 - Hofmann, T. A1 - Seeck, O. H. A1 - Kityk, A. A1 - Mazza, M. G. A1 - Schönhals, Andreas A1 - Huber, P. T1 - Self-assembly of liquid crystals in nanoporous solids for adaptive photonic metamaterials N2 - Nanoporous media exhibit structures significantly smaller than the wavelengths of visible light and can thus act as photonic metamaterials. Their optical functionality is not determined by the properties of the base materials, but rather by tailored, multiscale structures, in terms of precise pore shape, geometry, and orientation. Embedding liquid crystals in pore space provides additional opportunities to control light–matter interactions at the single-pore, meta-atomic scale. Here, we present temperature-dependent 3D reciprocal space mapping using synchrotron-based X-ray diffraction in combination with high-Resolution birefringence experiments on disk-like mesogens (HAT6) imbibed in self-ordered arrays of parallel cylindrical pores 17 to 160 nm across in monolithic anodic aluminium oxide (AAO). In agreement with Monte Carlo computer simulations we observe a remarkably rich self-assembly behaviour, unknown from the bulk state. It encompasses transitions between the isotropic liquid state and discotic stacking in linear columns as well as circular concentric ring formation perpendicular and parallel to the pore axis. These textural transitions underpin an optical birefringence functionality, tuneable in magnitude and in sign from positive to negative via pore size, pore surface-grafting and temperature. Our study demonstrates that the advent of large-scale, self-organised nanoporosity in monolithic solids along with confinement-controllable phase behaviour of liquid-crystalline matter at the single-pore scale provides a reliable and accessible tool to design materials with adjustable optical anisotropy, and thus offers versatile pathways to finetune polarisation-dependent light propagation speeds in materials. Such a tailorability is at the core of the emerging field of transformative optics, allowing, e.g., adjustable light absorbers and extremely thin metalenses. KW - Discotic Liquid Crystals PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-499601 DO - https://doi.org/10.1039/c9nr07143a SP - 1 EP - 14 PB - RSC Royal Society of Chemistry AN - OPUS4-49960 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meierhofer, F. A1 - Dissinger, F. A1 - Weigert, Florian A1 - Resch-Genger, Ute A1 - Waldvogel, S. R. A1 - Voss, T. T1 - Citric-Acid-Based Carbon Dots with Luminescence Quantum Yields > 50%: spectral tuning of the luminescence by ligand exchange and pH adjustment N2 - We report the synthesis and characterization of carbon nanodots (CDs) with high quantum yield (>50%) and tailored optical absorption as well as emission properties. A well-described protocol with polyethyleneimine (PEI) as amine precursor is used as a reference to a new CD system which is stabilized by aromatic 2,3-diaminopyridine (DAP) molecules instead. The DAP stabilizer is installed in order to red-shift the absorption peak of the n-π* electron transition allowing efficient radiative recombination and light emission. Size, shape, and chemical composition of the samples are determined by (HR)TEM, EDX and FTIR-spectroscopy. Optical parameters are investigated using UV-VIS, PL and QY measurements. Several parameters such as concentration, excitation wavelength and pH are studied. Zeta-potential analysis indicate that pH-induced (de-)protonation processes of functional moieties directly affect the n-π* energy bands. This results in unique pH-dependent absorption and emission characteristics which are discussed on the specific chemical composition of each CD system. T2 - MRS 2019 CY - Boston, MA, USA DA - 03.12.2019 KW - Nanoparticle KW - Carbon dot KW - Surface chemistry KW - Fluorescence KW - PH KW - Ligand KW - FTIR KW - Synthesis KW - Characterization PY - 2019 AN - OPUS4-49968 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Frielinghaus, H. A1 - Butler, P. D. A1 - Pauw, Brian Richard A1 - Rennie, A. R. T1 - Eleventh canSAS Meeting: International Cooperation and Collaboration in Small-Angle Scattering N2 - The eleventh canSAS workshop was held in Freising, Germany, July 8–10, 2019. These international meetings, promoting collective action for nomadic small-angle scatterers, have been taking place since 1998 and act as forums to catalyze cooperation amongst the SAS community in order to provide better facilities and equipment, combined with reliable data interpretation and analysis. The meeting attracted over 60 participants from major neutron and X-ray laboratories, as well as manufacturers of SAXS equipment, and users from academia and industry. There was also a wide geographical spread with participants from Australia, Asia, and North America joining European colleagues. T2 - canSAS XI CY - Freising, Germany DA - 08.07-2019 KW - Small angle scattering KW - Conference KW - Standardisation PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-498192 DO - https://doi.org/10.1080/08940886.2019.1680215 SN - 0894-0886 SN - 1931-7344 VL - 32 IS - 6 SP - 48 EP - 49 PB - Taylor & Francis CY - Abingdon, UK AN - OPUS4-49819 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kockert, M. A1 - Mitdank, R. A1 - Zykov, A. A1 - Kowarik, Stefan A1 - Fischer, F. T1 - Absolute Seebeck coefficient of thin platinum films N2 - The influence of size effects on the thermoelectric properties of thin platinum films is investigated and compared to the bulk. Structural properties, like the film thickness and the grain size, are varied. We correlate the electron mean free path with the temperature dependence of the electrical conductivity and the absolute Seebeck coefficient SPt of platinum. A measurement platform was developed as a standardized method to determine SPt and show that SPt,film is reduced compared to SPt,bulk. Boundary and surface scattering reduce the thermodiffusion and the phonon drag contribution to SPt,film by nearly the same factor. We discuss in detail on behalf of a model, which describes the temperature dependence of the absolute Seebeck coefficient, the influence of size effects of electron-phonon and phonon-phonon interaction on SPt. KW - Thin magnetic films PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-499007 DO - https://doi.org/10.1063/1.5101028 SN - 0021-8979 VL - 126 SP - 105106 PB - AIP AN - OPUS4-49900 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Backes, Sebastian A1 - Fahrbach, M. A1 - Cappella, Brunero A1 - Peiner, E. T1 - Scanning characterization of polymer coating layers using contact resonance with piezoresistive microprobes N2 - The motivation and the measurement setup for large fast-scanning piezoresistive cantilevers are presented. The theory behind the measurements of mechanical properties through contact resonance is explained. Results of such measurements on two kinds of polymer are compared to results from force distance curves. Noise, time-dependency and dependency of the results on the vibration mode are identified as challenges of contact resonance. T2 - 19th International Conference and Exhibition (European Society for Precision engineering and Nanotechnology/EUSPEN) CY - Bilbao, Spain DA - 03.06.2019 KW - Force distance curves KW - Contact resonance KW - Lubricants KW - Photoresist PY - 2019 AN - OPUS4-49903 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Backes, Sebastian A1 - Cappella, Brunero T1 - Force distance curves (FDC) & contact resionance (CR) measurement modes for mechanical property measurements N2 - At the Stakeholder meeting of the EMPIR project “Multifunctional ultrafast microprobes for on-the-machine measurements”, details about two measurement modes were presented. Force distance curves and contact resonance measurements are compared. The basic principles are explained and exemplary measurements concerning mechanical properties of polymers are shown. T2 - 19th International Conference and Exhibition (European Society for Precision Engineering and Nanotechnology/EUSPEN) CY - Bilbao, Spain DA - 03.06.2019 KW - Force distance curve KW - Contact resonance KW - Lubricants KW - Photoresist PY - 2019 AN - OPUS4-49905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Friedrich, Sebastian A1 - Cappella, Brunero T1 - Characterization of lubricants using AFM force-distance curves N2 - Auf dünnen Filmen von Schmiermitteln wurden Kraft-Abstand-Kurven aufgenommen. Die Schmiermittel benetzen die AFM-Spitze, sodass eine Kapillarkraft auftritt. Diese hängt von der Form der Spitze sowie von physikalischen Eigenschaften wie Viskosität und Oberflächenspannung ab, die zusätzlich mit anderen Verfahren bestimmt wurden. So konnte ihr Einfluss auf die Kurvenform untersucht werden. N2 - Force-distance curves have been recorded on thin films of lubricants. The lubricants wet the AFM tip, which causes a capillary force. This force depends on the shape of the tip, as well as on physical properties like viscosity and surface tension, which have been determined additionally with other methods. This way, their influence on the shape of the curves could be analyzed. T2 - 60. Tribologie-Fachtagung der Gesellschaft für Tribologie/GfT CY - Göttingen, Germany DA - 23.09.2019 KW - AFM-Kraft-Abstand-Kurven KW - Schmiermittel KW - Viskosität PY - 2019 AN - OPUS4-49906 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nirmalananthan-Budau, Nithiya A1 - Rühle, Bastian A1 - Geißler, Daniel A1 - Moser, Marko A1 - Kläber, Christopher A1 - Schäfer, A. A1 - Resch-Genger, Ute T1 - Multimodal cleavable reporters for quantifying carboxy and amino groups on organic and inorganic nanoparticles N2 - Organic and inorganic nanoparticles (NPs) are increasingly used as drug carriers, fluorescent sensors, and multimodal labels in the life and material sciences. These applications require knowledge of the chemical nature, total number of surface groups, and the number of groups accessible for subsequent coupling of e.g., antifouling ligands, targeting bioligands, or sensor molecules. To establish the concept of catch-and-release assays, cleavable probes were rationally designed from a quantitatively cleavable disulfide moiety and the optically detectable reporter 2-thiopyridone (2-TP). For quantifying surface groups on nanomaterials, first, a set of monodisperse carboxy-and amino-functionalized, 100 nm-sized polymer and silica NPs with different surface group densities was synthesized. Subsequently, the accessible functional groups (FGs) were quantified via optical spectroscopy of the cleaved off reporter after its release in solution. Method validation was done with inductively coupled plasma optical emission spectroscopy (ICP-OES) utilizing the sulfur atom of the cleavable probe. This comparison underlined the reliability and versatility of our probes, which can be used for surface group quantification on all types of transparent, scattering, absorbing and/or fluorescent particles. The correlation between the total and accessible number of FGs quantified by conductometric titration, qNMR, and with our cleavable probes, together with the comparison to results of conjugation studies with differently sized biomolecules reveal the potential of catch-and-release reporters for surface analysis. Our findings also underline the importance of quantifying particularly the accessible amount of FGs for many applications of NPs in the life sciences. KW - Advanced Materials KW - Surface Chemistry KW - Organic–inorganic nanostructures KW - Funtional Groups KW - Quantitative Analysis PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-499081 DO - https://doi.org/10.1038/s41598-019-53773-3 VL - 9 SP - 17577-1 EP - 17577-11 PB - Springer Nature CY - London AN - OPUS4-49908 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 - JOUR A1 - Bastos, V. A1 - Oskoei, P. A1 - Andresen, Elina A1 - Saleh, Maysoon I. A1 - Rühle, Bastian A1 - Resch-Genger, Ute A1 - Oliveira, H. T1 - Stability, dissolution, and cytotoxicity of NaYF4‑upconversion nanoparticles with different coatings N2 - Upconversion nanoparticles (UCNPs) have attracted considerable attention owing to their unique photophysical properties. Their utilization in biomedical applications depends on the understanding of their transformations under physiological conditions and their potential toxicity. In this study, NaYF4: Yb,Er UCNPs, widely used for luminescence and photophysical studies, were modified with a set of four different coordinatively bound surface ligands, i.e., citrate, alendronate (AA), ethylendiamine tetra(methylene phosphonate) (EDTMP), and poly(maleic anhydride-alt-1-octadecene) (PMAO), as well as silica coatings with two different thicknesses. Subsequently, the aging-induced release of fluoride ions in water and cell culture media and their cytotoxic profile to human keratinocytes were assessed in parallel to the cytotoxic evaluation of the ligands, sodium fluoride and the lanthanide ions. The cytotoxicity studies of UCNPs with different surface modifications demonstrated the good biocompatibility of EDTMP-UCNPs and PMAO-UCNPs, which is in line with the low amount of fluoride ions released from these samples. An efficient prevention of UCNP dissolution and release of cytotoxic ions, as well as low cytotoxicity was also observed for UCNPs with a sufficiently thick silica shell. Overall, our results provide new insights into the understanding of the contribution of surface chemistry to the stability, dissolution behavior, and cytotoxicity of UCNPs. Altogether, the results obtained are highly important for future applications of UCNPs in the life sciences and bioimaging studies. KW - Nano KW - Nanomaterial KW - Upconversion nanoparticle KW - Lanthanide KW - Photoluminescence KW - Quantum yield KW - Photophysics KW - Excitation power density KW - Surface chemistry KW - Coating PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-544681 DO - https://doi.org/10.1038/s41598-022-07630-5 SN - 2045-2322 VL - 12 SP - 1 EP - 13 PB - Springer Nature CY - London AN - OPUS4-54468 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Florian, Camilo A1 - Kirner, Sabrina V. A1 - Déziel, J.-L. A1 - Wonneberger, R. A1 - Undisz, A. A1 - Wasmuth, Karsten A1 - Spaltmann, Dirk A1 - Siegel, J. A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Influence of oxidation in the formation and performance of laser-induced periodic surface structures N2 - The fabrication of laser-induced periodic surface structures (LIPSS) has been reported for metallic, semiconductor and dielectric materials when irradiated with linearly polarized ultrashort laser pulses. Different sets of processing parameters have been identified and extensively studied, allowing the use of LIPSS for applications in medicine, tribology and surface wetting to name a few. One important parameter that is often not considered is the laser-induced oxidation that is produced especially when oxidation prone materials are irradiated in air environment. This surface oxidation can potentially influence the final structures size, shape and orientation and modify their functionality in some specific applications. In this work, we first study the influence of the laser-induced oxidation layer on the formation of LIPSS by characterizing the response of the oxidation prone hard-coating material chromium nitride. Moreover, we employ complementary surface and depth-profiling analytic techniques to reveal morphological, chemical and structural features of different types of surface structures and LIPSS produced on titanium-based substrates. Finite-difference time-domain (FDTD) calculations finally explain how this superficial oxidation layer promotes the formation of a new type of low spatial frequency LIPSS. Also, we measure the depth-extent of the different oxides formed and demonstrate its beneficial influence for friction reduction and wear resistance applications. T2 - SPIE Photonics West Conference, Symposium "Laser-Based Micro- and Nano-Processing XVI" CY - San Francisco, CA, USA DA - 22.01.2022 KW - Laser-induced periodic surface structures (LIPSS) KW - Oxidation KW - Femtosecond laser KW - Laser processing KW - Finite-difference time-domain calculations (FDTD) PY - 2022 AN - OPUS4-54322 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strommer, Bettina A1 - Battig, Alexander A1 - Frasca, Daniele A1 - Schulze, Dietmar A1 - Huth, Christian A1 - Böhning, Martin A1 - Schartel, Bernhard T1 - Multifunctional Property Improvements by Combining Graphene and Conventional Fillers in Chlorosulfonated Polyethylene Rubber Composites N2 - The incorporation of nanoparticles like multilayer graphene (MLG) into elastomeric composites boosts their technical performance, such as their mechanical behavior and electrical conductivity. Common filler types (carbon black (CB) and aluminum trihydroxide (ATH)) generally fulfill single, specific purposes and are often used in high loadings. CB typically reinforces rubber mechanically, while ATH increases flame retardancy. Small amounts of MLG reduce these high filler contents and maintain the multifunctional characteristics of rubber composites. In chlorosulfonated polyethylene (CSM) + ATH, an intrinsically flame-retardant rubber was designed to achieve the highest standards such as maximum average of heat emission (MARHE) <90 kW m−2, 3 phrMLG was substituted for 15 phr CB and/or 3 phr ATH via an industrially applicable processing approach. Replacing either CB or ATH resulted in a property profile that was multifunctionally improved in terms of features such as mechanical performance, reduced sorption, and flame retardance. MLG nanocomposites are reported to show promise as an industrially utilizable route to obtain multifunctional high-performance rubbers. KW - Nanocomposites KW - Rubber KW - Multilayer graphene KW - Flame retardancy KW - Synergy KW - Nanoparticles KW - Elastomers PY - 2022 DO - https://doi.org/10.1021/acsapm.1c01469 SN - 2637-6105 VL - 4 IS - 2 SP - 1021 EP - 1034 PB - ACS Publ. CY - Washington, DC AN - OPUS4-54330 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - 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 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542576 DO - https://doi.org/10.1002/adem.202101344 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 - Agudo Jácome, Leonardo T1 - Navigating the Nanoworld: Understanding Materials Properties with the Transmission Electron Microscope N2 - The field of materials science is defined as “the study of the properties of solid materials and how those properties are determined by a material’s composition and structure.”. Many –if not most– of the materials that are produced nowadays owe their properties to structures engineered down to the nanoscopic level. This need has been partly realized thanks to the understanding of materials’ building blocks via characterization techniques that reach this level of resolution. Transmission electron microscopy, since its first implementation in the early 1930s (in Berlin), has been implemented to achieve imaging –and spectral– analysis at lateral resolutions down to the atomic level. In this contribution, a series of practical examples will be presented, where applied materials are characterized by a range of transmission electron microscopy techniques to understand structural and functional properties of a wide range of materials. Among these materials examples will be presented on structural conventionally and additively manufactured metallic alloys, high entropy alloys, dissimilar aluminum-to-steel welds, magnetic nanoparticles, ceramic coatings, high temperature oxidation products. Addressed will be either the effect of processing route or that of the exposure to experimental conditions similar to those found in the respective intended applications. T2 - UA/UAB/UAH MSE Graduate Seminar CY - Online meeting DA - 19.01.2022 KW - Transmission electron microscopy (TEM) KW - Characterization KW - Microstructure KW - 3D PY - 2022 AN - OPUS4-54238 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 - Ansari, A. A. A1 - Ou, Jun A1 - Würth, Christian A1 - Resch-Genger, Ute T1 - Preparation of core–shell structured NaYF4:Yb3+/ Tm3+@NaYF4:Yb3+/Er3+ nanoparticles with high sensitivity, low resolution and good reliability and application of their fluorescence temperature properties N2 - A series of NaYF4:Yb3+/Tm3+@NaYF4:Yb3+/Er3+ nanoparticles doped with Tm3+ and Er3+ were successfully prepared by the solvothermal method. Under 980 nm laser excitation, intense upconversion emission peaks of Tm3+ and Er3+ were observed for all samples. By doping Tm3+ and Er3+ with core–shell partitioning, not only a significant increase in fluorescence intensity could be achieved, but also simultaneous temperature measurements on multiple thermocouple energy levels could be realised. In addition, the temperature sensing performance of different thermocouple energy levels was also investigated, and it was found that the 3 F3 → 3 H6 and 1 G4 → 3 F4 thermocouple energy level pairs of Tm3+ were the best, with maximum absolute sensitivity and maximum relative sensitivity of up to 0.0250 K−1 and 2.155% K−1 respectively, higher than the sensitivity of other thermocouple energy levels. It has a temperature resolution of less than 0.0139 K, which is lower than that of most materials available today. By using this material as a probe to build a fiber optic temperature sensor platform, it was found to have reliable temperature measurement performance. KW - Flourescence KW - Optical probe KW - Sensor KW - Dye KW - Temperature KW - Nano KW - Particle KW - Upconversion KW - Lanthanide KW - Qantum yield KW - Quality assurance KW - Monitoring KW - Infrastructure PY - 2022 DO - https://doi.org/10.1039/d1ce01729b VL - 24 IS - 9 SP - 1752 EP - 1763 PB - RSC Publishing AN - OPUS4-54416 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan A1 - Jungnickel, H. A1 - Tentschert, J. A1 - Luch, A. A1 - Sogne, V. A1 - Maier, F. A1 - Burr, L. A1 - Schmid, D. A1 - Yoon, T.-H. A1 - Petters, R. A1 - Briffa, S.M. A1 - Valsami-Jones, E. T1 - Automation and Standardization—A Coupled Approach Towards Reproducible Sample Preparation Protocols for Nanomaterial Analysis N2 - Whereas the characterization of nanomaterials using different analytical techniques is often highly automated and standardized, the sample preparation that precedes it causes a bottleneck in nanomaterial analysis as it is performed manually. Usually, this pretreatment depends on the skills and experience of the analysts. Furthermore, adequate reporting of the sample preparation is often missing. In this overview, some solutions for techniques widely used in nano-analytics to overcome this problem are discussed. Two examples of sample preparation optimization by au-tomation are presented, which demonstrate that this approach is leading to increased analytical confidence. Our first example is motivated by the need to exclude human bias and focuses on the development of automation in sample introduction. To this end, a robotic system has been de-veloped, which can prepare stable and homogeneous nanomaterial suspensions amenable to a variety of well-established analytical methods, such as dynamic light scattering (DLS), small-angle X-ray scattering (SAXS), field-flow fractionation (FFF) or single-particle inductively coupled mass spectrometry (sp-ICP-MS). Our second example addresses biological samples, such as cells exposed to nanomaterials, which are still challenging for reliable analysis. An air–liquid interface has been developed for the exposure of biological samples to nanomaterial-containing aerosols. The system exposes transmission electron microscopy (TEM) grids under reproducible conditions, whilst also allowing characterization of aerosol composition with mass spectrometry. Such an approach enables correlative measurements combining biological with physicochemical analysis. These case studies demonstrate that standardization and automation of sample preparation setups, combined with appropriate measurement processes and data reduction are crucial steps towards more reliable and reproducible data. KW - Sample preparation KW - Automation KW - Nanomaterial analysis KW - Standardization PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543988 DO - https://doi.org/10.3390/molecules27030985 VL - 27 IS - 3 SP - 1 EP - 22 PB - MDPI AN - OPUS4-54398 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Knigge, Xenia T1 - First Experiences with the new HAXPES@BAM N2 - This talk was part of the inauguration event for the new x-ray photoelectron spectrometer with the possibility to measure HAXPES (hard energy x-ray photoelectron spectroscopy). With HAXPES detailed chemical information can now be gained not only from the first outermost nanometres of the sample surface, but also from deeper regions. In this talk first results and experiences handling the spectrometer are shown. T2 - Inauguration of the HAXPES@BAM - A new Hard-X-Ray Photoelectron Spectrometer CY - Online meeting DA - 25.01.2022 KW - HAXPES KW - Nano@BAM KW - Surface Analysis KW - XPS PY - 2022 UR - https://www.bam.de/Content/EN/Events/2022/2022-01-25-hapex.html AN - OPUS4-54434 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Epishin, A. I. A1 - Petrushin, N. V. A1 - Svetlov, I. L. A1 - Nolze, Gert T1 - Model for Forecasting Temperature Dependence of γ/γ' Misfit in Heat-Resistant Nickel Alloys N2 - An analytical model for forecasting the temperature dependence of γ/γ' misfit in heat-resistant nickel alloys is proposed. The model accounts for the concentration dependences of the periods of crystalline lattices of the γ and γ' phases (Vegard law), thermal expansion of the γ and γ' lattices, and dissolution of the γ' phase at high temperatures. Adequacy of calculations of misfit is confirmed by comparison with the results of measurements using methods of X-ray and neutron diffraction. The model is applied for development of a nickel alloy with positive misfit. KW - Heat-resistant nickel alloys KW - Dimensional mismatch of crystalline lattice periods (misfit) KW - Microstructure evolution PY - 2022 DO - https://doi.org/10.1134/S2075113322010105 SN - 2075-1133 VL - 13 IS - 1 SP - 7 EP - 16 PB - Springer AN - OPUS4-54379 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Qiao, Linan A1 - Nagelschmidt, Sven A1 - Herbrich, Uwe A1 - Keller, Christian T1 - Introduction of a Power Law Time-Temperature Equivalent Formulation for the Description of Thermorheologically Simple and Complex Behavior N2 - Abstract: In this work, a conceptual framework is suggested for analyzing thermorheologically simple and complex behavior by using just one approach. Therefore, the linear relation between master time and real time which is required in terms of the time-temperature superposition principle was enhanced to a nonlinear equivalent relation. Furthermore, we evaluate whether there is any relation among well-known existing time-temperature equivalent formulations which makes it possible to generalize different existing formulations. For this purpose, as an example, the power law formulation was used for the definition of the master time. The method introduced here also contributes a further framework for a unification of established time-temperature equivalent formulations, for example the time-temperature superposition principle and time-temperature parameter models. Results show, with additional normalization conditions, most of the developed time-temperature parameter models can be treated as special cases of the new formulation. In the aspect of the arrow of time, the new defined master time is a bended arrow of time, which can help to understand the corresponding physical meaning of the suggested method. KW - bended arrow of time KW - time-temperature superposition principle KW - time-temperature equivalent formulation PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543800 DO - https://doi.org/10.3390/ma15030726 VL - 15 IS - 3 SP - 1 EP - 11 PB - MDPI AN - OPUS4-54380 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Usmani, S. A1 - Voss, L. A1 - Stephan, Ina A1 - Hübert, Thomas A1 - Kemnitz, E. T1 - Improved Durability of Wood Treated with Nano Metal Fluorides against Brown-Rot and White-Rot Fungi N2 - Low-water soluble metal fluorides such as magnesium fluoride (MgF2) and calcium Fluoride (CaF2) were evaluated for decay protection of wood. Initially, the biocidal efficacy of nano metal fluorides (NMFs) against wood destroying fungi was assessed with an in-vitro agar test. The results from the test showed that agar medium containing MgF2 and CaF2 was more efficient in preventing fungal decay than stand-alone MgF2 or CaF2. These metal fluorides, in their nanoscopic form synthesized using fluorolytic sol-gel synthesis, were introduced into the sapwood of Scots pine and beech wood and then subjected to accelerated ageing by leaching (EN 84). MAS 19F NMR and X-ray micro CT images showed that metal fluorides were present in treated wood, unleached and leached. Decay resistance of Scots pine and beech wood treated with NMFs was tested against Wood destroying fungi Rhodonia placenta and Trametes versicolor in accordance with EN 113. Results revealed that mass losses were reduced to below 3% in wood treated with the combination of MgF2 and CaF2. It is concluded that NMFs provide full protection to wood even after it has been leached and can be used as wood preservatives in outdoor environments. KW - Nanoparticles KW - Fluoride KW - Wood protection KW - Fluorolytic sol-gel synthesis KW - Brown-rot fungi KW - White-rot fungi KW - Basidiomycetes PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543877 DO - https://doi.org/10.3390/app12031727 VL - 12 IS - 3 SP - 1 EP - 11 PB - MDPI AN - OPUS4-54387 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Le Guevel, X. A1 - Wegner, Karl David A1 - Würth, Christian A1 - Baulin, V. A. A1 - Musnier, B. A1 - Josserand, V. A1 - Resch-Genger, Ute A1 - Koll, J-C T1 - Tailoring the SWIR emission of gold nanoclusters by surface ligand rigidification and their application in 3D bioimaging N2 - The influence of solvent polarity and surface ligand rigidification on the SWIR emission profile of gold nanoclusters with an anistropic surface was investigated. A strong enhancement of the SWIR emission band at 1200 nm was observed when measuring in different local environments: in solution, in polymer composites, and in solids. SWIR in vivo imaging of mice assisted by deep learning after intravenous administration of these gold nanoclusters provides high definition pseudo-3D views of vascular blood vessels. KW - Nano KW - Nanomaterial KW - Metal cluster KW - Photoluminescence KW - Quantum yield KW - Photophysics KW - Lifetime KW - Sensor KW - NIR KW - SWIR KW - Ligand KW - Gold KW - Mechanism KW - Charge transfer KW - Enhancement strategy KW - Imaging KW - Application KW - Contrast agent PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543582 DO - https://doi.org/10.1039/D1CC06737K VL - 58 IS - 18 SP - 2967 EP - 2970 PB - RSC AN - OPUS4-54358 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Navarro, L. A1 - Thünemann, Andreas A1 - Klinger, D. T1 - Solvent Annealing of Striped Ellipsoidal Block Copolymer Particles: Reversible Control over Lamellae Asymmetry, Aspect Ratio, and Particle Surface N2 - Solvent annealing is a versatile tool to adjust the shape and morphology of block copolymer (BCP) particles. During this process, polar solvents are often used for block-selective swelling. However, such water-miscible solvents can induce (partial) solubilization of one block in the surrounding aqueous medium, thus, causing complex structural variations and even particle disassembly. To reduce the complexity in morphology control, we focused on toluene as a nonpolar polystyrene-selective solvent for the annealing of striped polystyrene-b-poly(2-vinylpyridine) (PS-b-P2VP) ellipsoids. The selective stretching of PS chains produces unique asymmetric lamellae structures, which translate to an increase in the particle aspect ratio after toluene evaporation. Complete reversibility is achieved by changing to chloroform as a nonselective solvent. Moreover, surfactants can be used to tune block-selective wetting of the particle surface during the annealing; for example, a PS shell can protect the internal lamellae structure from disassembly. Overall, this versatile postassembly process enables the tailoring of the structural features of striped colloidal ellipsoids by only using commercial BCPs and solvents. KW - Small-angle X-ray scattering KW - SAXS KW - Nanoparticle KW - Polymer PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543731 DO - https://doi.org/10.1021/acsmacrolett.1c00665 VL - 11 IS - 3 SP - 319 EP - 335 PB - American Chemical Society AN - OPUS4-54373 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg A1 - Chemello, Giovanni A1 - Hodoroaba, Vasile-Dan 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 - CONF A1 - Radnik, Jörg T1 - Colours, nano and surface N2 - The basic ideas of colours and pigments are presented. The correlation between nanomaterials and colours are explained. Different methods are presented for investigating nanoparticles and their surface. At the end a case study is presented explaining the importance of coating for the properties of nanoparticles. T2 - Eingeladener Vortrag im Deutschen Lackmuseum (Münster) CY - Online meeting DA - 11.02.2022 KW - Pigments KW - Surface Analytics KW - Coatings PY - 2022 AN - OPUS4-54376 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg T1 - Surface Analysis and Context of the New HAXPES@BAM N2 - The Competence Centre nano@BAM is presenting a new X-ray Photoelectron Spectrometer – the HAXPES (XPS at hard energy) – for researching advanced materials at the nanoscale. With HAXPES detailed chemical information can now be gained not only from the first outermost nanometres of the sample surface, but also from deeper regions. Top international experts will share their knowledge and key findings on how to utilise HAXPES for exploring the surface of various advanced materials. Following the lectures, we will show you a short demo of the new instrument and answer your questions. T2 - Inauguration of the HAXPES@BAM - A new Hard-X-Ray Photoelectron Spectrometer CY - Online meeting DA - 25.01.2022 KW - XPS KW - HAXPES KW - Nano@BAM KW - Surface Analysis PY - 2022 UR - https://www.bam.de/Content/EN/Events/2022/2022-01-25-hapex.html AN - OPUS4-54377 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 - JOUR A1 - Crouzier, L. A1 - Feltin, N. A1 - Delvallée, A. A1 - Pellegrino, Francesco A1 - Maurino, V. A1 - Cios, Grzegorz A1 - Tokarski, T. A1 - Salzmann, Christoph A1 - Deumer, J. A1 - Gollwitzer, C. A1 - Hodoroaba, Vasile-Dan T1 - Correlative analysis of the dimensional properties of bipyramidal titania nanoparticles by complementing electron microscopy with other methods N2 - In this paper, the accurate determination of the size and size distribution of bipyramidal anatase nanoparticles (NPs) after deposition as single particles on a silicon substrate by correlative Scanning Electron Microscopy (SEM) with Atomic Force Microscopy (AFM) analysis is described as a new measurement procedure for metrological purposes. The knowledge of the exact orientation of the NPs is a crucial step in extracting the real 3D dimensions of the particles. Two approaches are proposed to determine the geometrical orientation of individual nano‐bipyramides: (i) AFM profiling along the long bipyramid axis and (ii) stage tilting followed by SEM imaging. Furthermore, a recently developed method, Transmission Kikuchi Diffraction (TKD), which needs preparation of the crystalline NPs on electron‐transparent substrates such as TEM grids, has been tested with respect to its capability of identifying the geometrical orientation of the individual NPs. With the NPs prepared homogeneously on a TEM grid, the transmission mode in a SEM, i.e., STEM‐in‐SEM (or T‐SEM), can be also applied to extract accurate projection dimensions of the nanoparticles from the same sample area as that analysed by SEM, TKD and possibly AFM. Finally, Small Angle X‐ray Scattering (SAXS) can be used as an ensemble technique able to measure the NPs in liquid suspension and, with ab‐initio knowledge of the NP shape from the descriptive imaging techniques, to provide traceable NP size distribution and particle concentration. KW - Nanoparticles KW - Complex-shape KW - Bipyramid KW - Electron microscopy KW - AFM KW - Size measurements KW - TKD KW - STEM-in-SEM KW - SAXS KW - Nanoparticle concentration KW - Correlative analysis PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-539888 DO - https://doi.org/10.3390/nano11123359 SN - 2079-4991 VL - 11 IS - 12 SP - 1 EP - 19 PB - MDPI CY - Basel AN - OPUS4-53988 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Schmidt, Alexandra A1 - Bresch, Harald A1 - Kämpf, K. A1 - Bachmann, V. A1 - Peters, T. A1 - Kuhlbusch, T. T1 - Development of a specific OECD Test Guideline on Particle Size and Particle Size Distribution of Nanomaterials N2 - In this research project, a new OECD Test Guideline (TG) for the determination of “Particle Size and Particle Size Distributions of Nanomaterials” was developed as the existing OECD TG 110 is considered to be outdated in terms of applicable size range (not covering sizes <200 nm) and methods. By its scope with an applicable size range from 1 to 1000 nm the new Test Guideline (TG PSD) covers the whole nanoscale. The TG PSD is applicable for particulate and fibrous nanomaterials. The prescribed, pairwise measurement of fibre diameter and length in the TG PSD allows for the first time to differen-tiate fibres with regard to their size-dependent hazard properties. Measurement instructions for each included method were validated within two separated interlaboratory comparisons, as a distinction between near spherical particles and fibres when applying the methods has to be made. Besides information on content and structure of the TG PSD, this final report outlines essential steps, considerations and organisational aspects during the development of the TG. Insights into the selec-tion, preparation and prevalidation of test materials used in the interlaboratory comparison are given. Finally, main results of the interlaboratory comparisons and their impacts on the TG PSD are pre-sented. N2 - Im Rahmen des Forschungsprojekts wurde eine neue OECD-Prüfrichtlinie (TG) für die Bestimmung von Partikelgrößen und Partikelgrößenverteilungen von Nanomaterialien entwickelt, da die existie-rende OECD TG 110 zur Bestimmung von Partikelgrößen in Bezug auf den anwendbaren Größenbe-reich und die gegebenen Methoden veraltet ist bzw. den Nanometerbereich < 200 nm nicht abdeckt. Mit ihrem Anwendungsbereich von 1 bis 1000 nm deckt die neue Prüfrichtlinie (TG PSD) die gesamte Nanoskala ab. Die TG PSD ist für partikel- und faserförmige Nanomaterialien anwendbar. Durch die, in der TG PSD vorgeschriebene, paarweise Messung von Faserdurchmesser und -länge ermöglicht diese TG zum ersten Mal Fasern hinsichtlich ihrer größenabhängigen Gefahrstoffeigenschaften zu unter-scheiden. Die Messanweisungen aller enthaltenen Methoden wurden im Rahmen von zwei getrennten Ringversuchen validiert, da bei der Anwendung der Methoden eine Unterscheidung zwischen Parti-keln und Fasern gemacht werden muss. Neben Angaben zum Inhalt und Struktur der TG PSD, befasst sich der vorliegende Abschlussbericht mit den wesentlichen Schritten, Überlegungen und organisatorischen Aspekten bei der Entwicklung der Prüfrichtlinie. Darüber hinaus werden Einblicke in die Auswahl, Vorbereitung und Prävalidierung der im Ringversuch verwendeten Testmaterialien gegeben. Schließlich werden die wichtigsten Ergeb-nisse aus den Ringversuchen und ihre Auswirkungen auf die TG PSD vorgestellt. KW - Nano KW - OECD KW - Particle size distribution KW - Testguideline KW - Nanoparticle PY - 2021 VL - 2021 SP - 1 EP - 47 PB - German Environment Agency CY - Dessau AN - OPUS4-54021 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Advanced Characterization of the Surface Morphology and Chemistry within nano@BAM N2 - Both essential aspects of the surface of solid matter, its morphology and chemistry, are studied traditionally at BAM starting in the 60’s with different cyclical research focus areas, mostly related either to applicative research or method development. In the recent years, the focus has shifted almost exclusively to the nano-analytics of advanced materials such as complex nanoparticles, (ultra)thin films/coatings, nanocomposites, 2D materials, energy materials, etc. This is also the reason why BAM has established recently the new Competence Center nano@BAM (www.bam.de/Navigation/DE/Themen/Material/Nanotechnologie/sichere-nanomaterialien.html) with the five sub-fields nanoCharacterisation, nanoMaterial, nanoSafety, nanoData and nanoTechnology. The link to the BAM central guidelines to the safety in technology and chemistry is given by the development of reference products such as reference measurement procedures, reference (nano)materials, and newly reference data sets. Thus, an internationally well-networked group in surface analysis has been established @BAM, with regular contributions to integral analytical characterization with metrological and standardization background. Examples of newly developed methodical approaches will be given with an emphasis on correlative nano-analysis of morphology and chemistry of nanomaterials. Correlative imaging by STEM-in-SEM with high-resolution SEM and EDX, and further with AFM or the new technique TKD (Transmission Kikuchi Diffraction) will be explained on various examples of nanostructures, both as starting materials and embedded/functionalized nanoparticles in products. The unique analytical benefits of the Auger electron probe as a veritable nano-tool for surface chemistry will be highlighted. The panoply of advanced surface characterization methods @BAM is completed by discussing examples of hybrid analysis of the bulk of nanomaterials by X-ray Spectroscopy with the highest surface-sensitive methods X-ray Photoelectron Spectroscopy (XPS) and Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS). Particularly for the analysis of the surface chemistry of nanostructures, such as the completeness of the shells of core-shell nanoparticles or in-depth and lateral gradients of chemistry within mesoporous thin layers, the latter methods are inherent. Other special developments like approaches for the quantitative determination of the roughness of particle surface by electron microscopy or for the quantitative determination of the porosity of thin mesoporous layers by electron probe microanalysis (EPMA) with SEM will be presented in conjunction with the corresponding advanced materials studied. Current research projects, promising ideas, including ongoing (pre-)standardization activities in the field of the challenging nano/surface analysis will be touched systematically, with the open goal of identifying future bilateral cooperation possibilities between EMPA and BAM. T2 - EMPA-Kolloquium CY - Online meeting DA - 01.12.2021 KW - Nanoparticles KW - Nano@BAM KW - Nanomaterials KW - Surface morphology and chemistry KW - Correlative analysis PY - 2021 AN - OPUS4-54039 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dudziak, Mateusz A1 - Topolniak, Ievgeniia A1 - Silbernagl, Dorothee A1 - Altmann, Korinna A1 - Sturm, Heinz T1 - Long-time behavior of surface properties of microstructures fabricated by multiphoton lithography N2 - The multiphoton lithography (MPL) technique represents the future of 3D microprinting, enabling the production of complex microscale objects with high precision. Although the MPL fabrication parameters are widely evaluated and discussed, not much attention has been given to the microscopic properties of 3D objects with respect to their surface properties and time-dependent stability. These properties are of crucial importance when it comes to the safe and durable use of these structures in biomedical applications. In this work, we investigate the surface properties of the MPL-produced SZ2080 polymeric microstructures with regard to the physical aging processes during the post-production stage. The influence of aging on the polymeric microstructures was investigated by means of Atomic Force Microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS). As a result, a time-dependent change in Young’s Modulus, plastic deformation, and adhesion and their correlation to the development in chemical composition of the surface of MPL-microstructures are evaluated. The results presented here are valuable for the application of MPL-fabricated 3D objects in general, but especially in medical technology as they give detailed information of the physical and chemical time-dependent dynamic behavior of MPL-printed surfaces and thus their suitability and performance in biological systems. KW - Multiphoton lithography KW - Additive manufacturing KW - Microfabrication KW - SZ2080 negative photo-resist KW - Young´s modulus KW - Aging KW - Surface properties KW - X-ray photoelectron spectroscopy KW - Atomic force microscopy KW - Force-distance-curve PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542166 DO - https://doi.org/10.3390/nano11123285 SN - 2079-4991 VL - 11 IS - 12 SP - 1 EP - 12 PB - MDPI CY - Basel AN - OPUS4-54216 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Hodoroaba, Vasile-Dan A1 - Fontanges, R. A1 - Delvallée, A. A1 - Deumer, J. A1 - Salzmann, C. A1 - Crouzier, L. A1 - Gollwitzer, C. A1 - Klein, T. A1 - Koops, R. A1 - Sebaihi, N. A1 - Pauw, Brian Richard A1 - Smales, Glen Jacob A1 - Artous, S. A1 - Taché, O. A1 - Feltin, N. T1 - Report on full algorithm sequences for nanoparticle detection and size measurement as developed on both a physical basis and by machine learning N2 - he main objective of the nPSize project is to improve the measurement capabilities for nanoparticle size based on both measurement methods traceable to SI units and new reference materials. Two basic approaches have been used in order to develop measurement procedures resulting in traceable results of the nanoparticle size distribution: physical modelling for the methods used in the project (TSEM, SEM, AFM and SAXS) and machine learning. Physical modelling: In this part, the physical models associated with different shape measurements for the techniques TSEM, SEM, AFM and SAXS have been collected and further developed with the aim to simulate the resulting signal as measured by the individual methods. Uncertainties and traceability associated with each model were investigated and evaluated. In the following, the progress on these physical models is reported for each individual method. Machine Learning modelling: The aim of this part is to use machine learning to enable automatic measurement of nanoparticle shape from expert a-priori information only. No physical model will be used as a-priori information in this task. The accuracy and traceability of the size results obtained by each technique will be analyzed and compared with the physical modelling. A machine learning database will then be used to create automatic detection algorithms. KW - Nanoparticles KW - Particle size distribution KW - SEM KW - TSEM KW - TEM KW - SAXS KW - AFM PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546531 DO - https://doi.org/10.5281/zenodo.5807864 SP - 1 EP - 20 PB - Zenodo CY - Geneva AN - OPUS4-54653 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Le Xuan, Hoa T1 - Gezieltes Crosslinking von Immunglobulinen mit ortspezifischen Bindern N2 - Die neue Crosslinking-Methode ist hilfreich, um Immunglobuline des Isotyps G ortspezifisch an ihrer Bindungsstelle mit Protein A oder G zu konjugieren. Die Kopplungen von Protein A und G konnten erfolgreich an Maus- und Human-IgG durchgeführt, sowie die Bedingungen untersucht und optimiert werden. Die Aktivierung von Protein G mit Glutaraldehyd erfolgt am besten bei pH 8 und die anschließende Kopplung mit Maus-IgG1 bei einem pH-Wert von 6. Jedoch wurden mit SIAB und Sulfo-SIAB als Crosslinker im Vergleich zu Glutaraldehyd noch höhere Signale erhalten. Für die Kopplung von SIAB sind 40% DMSO im Reaktionspuffer günstig, währenddessen Sulfo-SIAB gut wasserlöslich ist daher keine Lösungsvermittler benötigt. Es ergab sich ein optimaler pH-Wert von 7,4 um Protein A mit SIAB zu aktivieren und den gleichen pH-Wert um die Kopplung mit Maus-IgG1 durchzuführen. Für die Kopplung von Protein G mit Maus-IgG1 hingegen zeigten die Experimente, dass ein leicht saurer pH-Wert bei pH 6 für den IgG-Kopplungsschritt am günstigsten ist. Während die Inkubationszeit von Maus-IgG1 mit Protein G bei 16 h liegt, muss mit Protein A bis zu 40 h inkubiert werden, um das Kopplungsmaximum zu erreichen. Des Weiteren wurde das Crosslinking von Human-IgG (Herceptin) mit SIAB untersucht. Dabei zeigte sich, wie in der Abbildung 47 zu sehen ist, dass Protein A und G vergleichbar gut an Human-IgG zu koppeln sind. Für das Crosslinking von Protein G mit Maus-IgG1 ist dagegen ein deutlich besserer Umsatz im Vergleich zu Protein A zu erkennen (Abbildung 48). Heterobifunktionale Linker können mit der reaktiveren Gruppe die erste Bindung eingehen, um erst nach Zugabe eines weiteren Reagenzes die zweite Bindung auszubilden und zudem intramolekulare Reaktionen möglichst zu vermeiden. KW - Antikörper KW - Antibodies KW - Vernetzung KW - Immobilisierung KW - Immobilization KW - Herceptin KW - Human antibodies KW - Therapeutic antibodies KW - Diagnostic antibodies KW - Oriented immobilization PY - 2019 SP - 1 EP - 100 PB - Humboldt-Universität zu Berlin CY - Berlin AN - OPUS4-54658 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bahri, Marwa T1 - Ortsspezifische Biokonjugation von humanen Antikörpern mit IgG-bindenden Peptiden N2 - Es wurde im Rahmen dieser Arbeit eine neue Methode der Biokonjugation entwickelt, die es ermöglicht humane Antikörper ortspezifisch mit IgG-bindenden Peptiden zu konjugieren. Als Basis fungierte ein Peptid, welches für den Einsatz gezielt modifiziert wurde. So sollte am C-Terminus ein Biotin eingefügt werden, dass für die spätere Detektion der Biokonjugation genutzt werden kann, während am N-Terminus ein Cross-Linker für die kovalente Bindung zum Antikörper eingefügt wurde. Das Biotin wurde mittels Biotin-Lysin eingebaut. Dies hat den Vorteil, dass die modifizierte Aminosäure direkt in der SPPS genutzt werden kann. Auch der Cross-Linker soll schon während der SPPS in das Peptid integriert werden. Als Cross Linker wurden die zwei heterobifunktionellen Succinimidyl(3-bromoacetamid)propionate und Succinimidyl(4-iodacetyl)aminobenzoat untersucht. Die Aktivierung des Peptides mit dem SBAP-Cross-Linker erfolgte am besten im pH-Bereich zwischen 7,0 und 9,0. Die Modifizierung des Peptides mit dem Iodid-Cross-Linker SIAB unter den gleichen Bedingungen zeigte allerdings keine zufriedenstellenden Ergebnisse. Da das erste Peptid allerdings in den Folgeexperimenten sehr gute Ergebnisse zeigte, musste kein weiterer Linker getestet werden. Zusätzlich zu der Cross-Linker-Wahl sollte der Abstand zwischen dem Cross-Linker und dem Grundgerüst des Peptides auf den Einfluss der Bindung untersucht werden. Dazu wurden drei Kontrollpeptide synthetisiert, die entweder um zwei Aminosäuren zwischen dem ursprünglichen N-Terminus des Peptides und dem SBAP-Linker verlängert wurden, keinen SBAP-Linker beinhalten oder die Verlängerung ohne SBAP-Linker besaßen. Die erfolgreiche Synthese aller vier Peptide wurde mittels MALDI-TOF-MS bestätigt. KW - Peptide KW - Bioconjugation KW - Crosslinker PY - 2020 SP - 1 EP - 82 PB - Humboldt-Universität zu Berlin CY - Berlin AN - OPUS4-54659 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Völzke, Jule Lexa T1 - Herstellung und Charakterisierung Antigen-beschichteter Nanopartikel als Analoga von Virus-like Particles (VLP) N2 - In dieser Arbeit wurden drei verschiedene Nanomaterialien auf ihre Bindungsfähigkeit zu Proteinen untersucht. Zu Beginn standen dabei die Herstellung stabiler Dispersionen der einzelnen Nanopartikel und die Stabilität der gebildeten Konjugate im Vordergrund. Der Nachweis einer erfolgreichen Konjugatbildung, sprich der Beschichtung von Nanopartikel mit Proteinen, wurde sowohl qualitativ mittels DLS-Messungen als auch über quantitative Protein-Bestimmungen erbracht. Für die Quantifizierung konnten verschiedene Methoden eingesetzt werden. Neben der klassischen Vorgehensweise, welche indirekt über die Quantifizierung von ungebundenem Protein im Überstand erfolgt, konnten ihm Rahmen dieser Arbeit verschiedene direkte Bestimmungsmethoden entwickelt werden. So wurden mittels kolorimetrischer Tests, wie dem BCA-Assay und dem Bradford-Assay, Nanodiamantdispersionen mit Hilfe einer Korrekturwellenlänge vermessen und quantifiziert. Ebenso zum Einsatz kam die Methode der Aminosäureanalytik, welche aufgrund ihrer guten Rückführbarkeit auf Aminosäurestandards Ergebnisse mit hoher Richtigkeit generieren kann und ebenso die Detektion kleiner Proteinmengen möglich macht. Nach den erfolgten quantitativen Betrachtungen wurden die Protein-beschichteten Nanopartikel auf ihre Anwendbarkeit als Analoga von Virus-like Particles (VLP) bei einer Immunisierung zur Gewinnung von polyklonalen Antikörpern gegen humanes Ceruloplasmin in Kaninchen überprüft. Es konnte mittels ELISA gezeigt werden, dass die Konjugate erfolgreich für die Herstellung von Antikörpern eingesetzt werden können und im zeitlichen Verlauf einer Immunisierung eine Steigerung des Antikörper-Titers zu erreichen ist. KW - DLS KW - Dynamische Lichtstreuung KW - Aluminiumoxid KW - Nanodiamant KW - Gold-Nanopartikel KW - BSA KW - Albumin KW - Protein G KW - Ceruloplasmin KW - Immunpräzipitation KW - Ultraschall KW - BCA KW - Bradford-Assay KW - AAAA KW - Aromatische Aminosäureanalytik KW - ICP-MS KW - NaCl-Methode PY - 2018 SP - 1 EP - 107 PB - Humboldt-Universität zu Berlin CY - Berlin AN - OPUS4-54625 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -