TY - GEN A1 - Swimm, K. A1 - Scherdel, C. A1 - Reichenauer, G. A1 - Klobes, Peter T1 - Characterization of organic aerogels as model materials for thermal conductivity measurements KW - Aerogels KW - SEM KW - SAXS KW - N2 sorption KW - Hg porosimetry KW - Thermal conductivity KW - Porosity PY - 2008 UR - http://hasylab.desy.de/annual_report/files/2008/200838.pdf SP - 1 EP - 2 PB - DESY CY - Hamburg AN - OPUS4-21828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krause, B. A1 - Meyer, T. A1 - Sieg, H. A1 - Kästner, Claudia A1 - Reichardt, P. A1 - Tentschert, J. A1 - Jungnickel, H. A1 - Estrela-Lopis, I. A1 - Burel, A. A1 - Chevance, S. A1 - Gauffre, F. A1 - Jalili, P. A1 - Meijer, J. A1 - Böhmert, L. A1 - Braeuning, A. A1 - Thünemann, Andreas A1 - Emmerling, Franziska A1 - Fessard, V. A1 - Laux, P. A1 - Lampen, A. A1 - Luch, A. T1 - Characterization of aluminum, aluminum oxide and titanium dioxide nanomaterials using a combination of methods for particle surface and size analysis N2 - The application of appropriate analytical techniques is essential for nanomaterial (NM) characterization. In this study, we compared different analytical techniques for NM analysis. Regarding possible adverse health effects, ionic and particulate NM effects have to be taken into account. As NMs behave quite differently in physiological media, special attention was paid to techniques which are able to determine the biosolubility and complexation behavior of NMs. Representative NMs of similar size were selected: aluminum (Al0) and aluminum oxide (Al2O3), to compare the behavior of metal and metal oxides. In addition, titanium dioxide (TiO2) was investigated. Characterization techniques such as dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) were evaluated with respect to their suitability for fast characterization of nanoparticle dispersions regarding a particle's hydrodynamic diameter and size distribution. By application of inductively coupled plasma mass spectrometry in the single particle mode (SP-ICP-MS), individual nanoparticles were quantified and characterized regarding their size. SP-ICP-MS measurements were correlated with the information gained using other characterization techniques, i.e. transmission electron microscopy (TEM) and small angle X-ray scattering (SAXS). The particle surface as an important descriptor of NMs was analyzed by X-ray diffraction (XRD). NM impurities and their co-localization with biomolecules were determined by ion beam microscopy (IBM) and confocal Raman microscopy (CRM). We conclude advantages and disadvantages of the different techniques applied and suggest options for their complementation. Thus, this paper may serve as a practical guide to particle characterization techniques. KW - Small-angle X-ray scattering KW - SAXS PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-447057 DO - https://doi.org/10.1039/C8RA00205C SN - 2046-2069 VL - 8 IS - 26 SP - 14377 EP - 14388 PB - The Royal Society of Chemistry AN - OPUS4-44705 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thünemann, Andreas T1 - Characterization of (bio)macromolecules and polymeric materials with modern scattering methods N2 - The analysis of polymers, biopolymers and polymeric materials is of great interest in biomaterials science. Here small-angle x-ray scattering (SAXS), static light scatterin (SLS) and dynamic light scattering (DLS) are described. Current efforts for digitalization of this methods are explaind with respect to modern data science in biomedical research. T2 - MacroBio Summer School 2018: Biomaterial Science in View of Digitalization CY - Teltow, Germany DA - 24.09.2018 KW - Small-angle x-ray scattering KW - SAXS KW - Static light scattering KW - SLS KW - Dynamic light scattering KW - DLS KW - Biomaterials PY - 2018 AN - OPUS4-46051 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thünemann, Andreas T1 - Challenges of synthesis and analysis of core-shell nanoparticles for reference materials N2 - Core-shell nanoparticles are widespread in nature, industrial applications and nanotechnology research. Facile ways of modern synthesis will be discussed and possibilities to reveal their structures with small-angle X-ray scattering (SAXS). A recent review on using block copolymer templates as one of the most reliable routes for tuning size and shape of nanoparticles is provided by Li et al.1 Ferritin and apoferritin are archetypical examples for protein-based core-shell nanoparticles. Their structures are easily accessed by synchrotron SAXS2 but also with commercial instruments and allow fast performance tests.3 SASfit4 is a suitable program tool based on classical curve fitting and McSAS5 is a complementary program based on a Monte Carlo technique. Detailed refinements of SAXS data evaluation are on the way for better data analysis.6 A sub nanometer resolution is state-of-the-art for quantification of the size distribution of polyacrylic acid stabilized silver nanoparticles.3 Such particles are useful in catalysis.7 It was observed that the catalytic activity can be tuned easily by varying the shell material of the particles. T2 - NanoWorkshop 2018 (Workshop on reference nanomaterials, current situation and needs: development, measurement, standardization) CY - Berlin, Germany DA - 14.05.2018 KW - Small-angle X-ray scattering KW - SAXS KW - Nanoparticle PY - 2018 AN - OPUS4-44903 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sieg, H. A1 - Krause, B.-C. A1 - Kästner, Claudia A1 - Böhmert, L. A1 - Lichtenstein, D. A1 - Tentschert, J. A1 - Jungnickel, H. A1 - Laux, P. A1 - Braeuning, A. A1 - Fessard, V. A1 - Thünemann, Andreas A1 - Luch, A. A1 - Lampen, A. T1 - Cellular Effects of In Vitro-Digested Aluminum Nanomaterials on Human Intestinal Cells N2 - Aluminum (Al) can be taken up from food, packaging, or the environment and thus reaches the human gastrointestinal tract. Its toxic potential after oral uptake is still discussed. The fate of different solid and ionic Al species during the passage through the digestive tract is the focus of this research, as well as the cellular effects caused by these different Al species. The present study combines the physicochemical processing of three recently studied Al species (metallic Al0, mineral Al2O3, and soluble AlCl3) in artificial digestion fluids with in vitro cell systems for the human intestinal barrier. Inductively coupled plasma mass spectrometry (ICP-MS) and small-angle X-ray scattering (SAXS) methods were used to characterize the Al species in the artificial digestion fluids and in cell culture medium for proliferating and differentiated intestinal Caco-2 cells. Cytotoxicity testing and cellular impedance measurements were applied to address the effects of digested Al species on cell viability and cell proliferation. Microarray-based transcriptome analyses and quantitative real-time PCR were conducted to obtain a deeper insight into cellular mechanisms of action and generated indications for cellular oxidative stress and an influence on xenobiotic metabolism, connected with alterations in associated signaling pathways. These cellular responses, which were predominantly caused by formerly ionic Al species and only at very high concentrations, were not impacted by artificial digestion. A two-directional conversion of Al between ionic species and solid particles occurred throughout all segments of the gastrointestinal tract, as evidenced by the presence of nanoscaled particles. Nevertheless, this presence did not increase the toxicity of the respective Al species. KW - SAXS KW - Small-angle X-ray scattering KW - Nanoparticle PY - 2020 DO - https://doi.org/10.1021/acsanm.9b02354 VL - 3 IS - 3 SP - 2246 EP - 2256 PB - American Chemical Society AN - OPUS4-50632 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sieg, H. T1 - Cellular effects of Al-, Ti- and Zn-containing nanomaterials on intestinal cell lines in vitro N2 - Aluminium-, titanium- and zinc-containing chemicals are highly abundant in food, food contact materials and consumer products. Physical and chemical conversion might lead to a certain amount of nanoscaled particles that can be taken up by the gastrointestinal tract. Nanospecific effects such as higher reactivity, increased surface or altered uptake can increase hazardous potential for human health. The aim of this study as part of the european SolNanoTOX project is to characterize toxicological effects of Al-, Zn- and Ti-containing nanomaterials on intestinal cell lines. While toxicological potential of zinc species has been well studied, little is known about the effects of aluminium- and titanium-species. We have performed toxicological experiments on the human intestinal cell line Caco-2 for numerous endpoints: Cellular ATP and glutathione levels, apoptosis, necrosis, vesicular uptake, oxidative stress, growth rate and cell cycle modification. While zinc-containing controls showed toxic responses, our utilized aluminium- (elementary Al, γ-Al2O3) and titanium-species (TiO2, rutile) did not. Nevertheless, we detected some differences between both different aluminium nanoparticle species and aluminium ions with regard to cell viability. We also provide strong evidence for particle-specific uptake of aluminium and titanium in the intestinal cell line Caco-2. In summary, among the different tested endpoints, Al- and Ti-containing nanomaterials did not show any toxicity in intestinal cell lines in vitro. Nevertheless, this absence of effect was not due to an absence of exposure, since particle-specific uptake was reported. Metal particle uptake over a long time might therefore be relevant for risk assessment of aluminium- and titanium-containing food products. T2 - 8th International Nanotoxicology Congress CY - Boston, MA, USA DA - 01.06.2016 KW - Artificial digestion KW - SAXS KW - Cell viability KW - Toxicity PY - 2016 AN - OPUS4-36921 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Marc Benjamin T1 - BP150: Bio-SAXS of single-stranded DNA-binding proteins: Radiation protection by the compatible solute ectoine N2 - Small-angle X-ray scattering (SAXS) can be used for structural determination of biological macromolecules and polymers in their native states (e.g. liquid phase). This means that the structural changes of (bio-)polymers, such as proteins and DNA, can be monitored in situ to understand their sensitivity to changes in chemical environments. In an attempt to improve the reliability of such experiments, the reduction of radiation damage occurring from exposure to X-rays is required. One such method, is to use scavenger molecules to protect macromolecules against radicals produced during radiation exposure, such as reactive oxygen species (ROS). In this study we investigate the feasibility of applying the compatible solute, osmolyte and radiation protector Ectoine (THP(B)), as a scavenger molecule during SAXS measurements of the single-stranded DNA-binding protein Gene-V Protein (G5P/GVP). In this case, we monitor the radiation induced changes of G5P during bio-SAXS measurments and the resulting microscopic energy-damage relation was determined from microdosimetric calculations by Monte-Carlo based particle scattering simulations with TOPAS/Geant4 and a custom target-model. This resulted in a median-lethal energy deposit of pure G5P at 4 mg mL−1 of E1/2 = 7 ± 5 eV, whereas a threefold increase of energy-deposit was needed under the presence of Ectoine to reach the same level of damage. This indicates that Ectoine increases the possible exposure time before radiation-damage to G5P is observed. Furthermore, the dominant type of damage shifted from aggregation in pure solutions towards a fragmentation for solutions containing Ectoine as a cosolute. These results are interpreted in terms of indirect radiation damage by reactive secondary species, as well as post-irradiation effects, related to preferential-exclusion of the cosolute from the protein surface. Hence, Ectoine is shown to provide a non-disturbing way to improve structure-determination of proteins via bio-SAXS in future studies. T2 - DPG Frühjahrstagung CY - Dresden, Germany DA - 26.03.2023 KW - Bio-SAXS KW - BioSAXS KW - Compatible solute KW - Cosolute KW - DNA KW - Dosimetry KW - Ectoin KW - Ectoine KW - G5P KW - GVP KW - Gene five protein KW - Geant4 KW - Geant4-DNA KW - Hydroxyectoine KW - Ionizing radiation damage KW - LEE KW - McSAS3 KW - Microdosimetry KW - Monte-Carlo simulations KW - OH Radical KW - OH radical scavenger KW - Osmolyte KW - Particle scattering simulations KW - Protein KW - Proteins KW - Protein unfolding KW - ROS KW - Radiation damage KW - Radical Scavenger KW - SAXS KW - Single-stranded DNA-binding proteins KW - Small-angle xray scattering KW - Topas KW - Topas-MC KW - Topas-nBio KW - X-ray scattering KW - Radical scavenger KW - ssDNA PY - 2023 AN - OPUS4-57254 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Szczerba, Wojciech A1 - Riesemeier, Heinrich A1 - Thünemann, Andreas T1 - Bond length cntraction in gold nanoparticles N2 - The structure of nanoparticles typically differs from its bulk counterpart. Predominantly, the structures of gold nanoparticles have been under exceedingly intense discussion since the discovery of their high catalytic activity. We found an increasing bond length contraction with decreasing particle size for citrate-stabilized gold nanoparticles in aqueous solution as determined by in situ extended X-ray absorption fine structure (EXAFS) spectroscopy. Particle sizes and size distributions were determined by small-angle X-ray scattering. The analysis of the obtained EXAFS spectra employing ab initio calculations reveals that the Au–Au bond length undergoes a contraction of 2 pm for nanoparticles with a radius of 2.9 nm. NIST reference material RM 8011 gold nanoparticles with a radius of 4.4 nm exhibit a smaller contraction of approximately 1 pm. Finally, gold atoms in RM 8013 particles with a radius of 25.7 nm show distances of 288 pm— identical to the distance in gold foil—and exhibits bulk-like properties. The observed bond length contraction of gold nanoparticles in solution is significantly smaller than previously reported for gold nanoparticle deposited on surfaces, which is up to 15 pm. This indicates that the bond length contraction effect of 'free' and 'surfaceimmobilized' nanoparticles differ fundamentally. Such difference could be essential for the understanding of nanoparticle-supported catalysis. KW - Small-angle X-ray scattering KW - SAXS KW - EXAFS KW - XAFS KW - Nanoparticle KW - Gold PY - 2010 DO - https://doi.org/10.1007/s00216-010-4200-z SN - 1618-2642 SN - 1618-2650 VL - 398 IS - 5 SP - 1967 EP - 1972 PB - Springer CY - Berlin AN - OPUS4-22173 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hahn, Marc Benjamin T1 - BioSAXS models for TOPAS/Geant4 N2 - Models for TOPAS/Geant4 to estimate the microscopic dose received by biomolecules during bioSAXS experiments. The C++ classes in this repository extend the functionality of the TOPAS (http://www.topasmc.org/) Monte-Carlo program, which is itself a wrapper of the Geant4 MCS Toolkit (http://geant4.org). KW - TOPAS KW - TOPAS-nBio KW - Geant4 KW - Geant4-DNA KW - MCS KW - Microdosimetry KW - Protein KW - Proteins KW - Particle scattering KW - G5P KW - GV5 KW - SAXS KW - Monte-Carlo simulation KW - Dosimetry KW - Micorscopic dose-damage relation PY - 2022 UR - https://github.com/MarcBHahn/TOPAS-bioSAXS-dosimetry DO - https://doi.org/10.26272/opus4-55751 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-55751 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mantion, Alexandre A1 - Graf, P. A1 - Florea, I. A1 - Haase, A. A1 - Thünemann, Andreas A1 - Masic, A. A1 - Ersen, O. A1 - Rabu, P. A1 - Meier, W. A1 - Luch, A. A1 - Taubert, A. T1 - Biomimetic synthesis of chiral erbium-doped silver/peptide/silica core-shell nanoparticles (ESPN) N2 - Peptide-modified silver nanoparticles have been coated with an erbium-doped silica layer using a method inspired by silica biomineralization. Electron microscopy and small-angle X-ray scattering confirm the presence of an Ag/peptide core and silica shell. The erbium is present as small Er2O3 particles in and on the silica shell. Raman, IR, UV-Vis, and circular dichroism spectroscopies show that the peptide is still present after shell formation and the nanoparticles conserve a chiral plasmon resonance. Magnetic measurements find a paramagnetic behavior. In vitro tests using a macrophage cell line model show that the resulting multicomponent nanoparticles have a low toxicity for macrophages, even on partial dissolution of the silica shell. KW - Nanoparticle KW - Small-angle X-ray scattering KW - SAXS PY - 2011 DO - https://doi.org/10.1039/c1nr10930h SN - 2040-3364 SN - 2040-3372 VL - 3 IS - 12 SP - 5168 EP - 5179 PB - RSC Publ. CY - Cambridge AN - OPUS4-25422 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -