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 - TY - JOUR A1 - Haase, A. A1 - Rott, S. A1 - Mantion, Alexandre A1 - Graf, P. A1 - Plendl, J. A1 - Thünemann, Andreas A1 - Meier, W.P. A1 - Taubert, A. A1 - Luch, A. A1 - Reiser, G T1 - Effects of silver nanoparticles on primary mixed neural cell cultures: uptake, oxidative stress and acute calcium responses N2 - In the body, nanoparticles can be systemically distributed and then may affect secondary target organs, such as the central nervous system (CNS). Putative adverse effects on the CNS are rarely investigated to date. Here, we used a mixed primary cell model consisting mainly of neurons and astrocytes and a minor proportion of oligodendrocytes to analyze the effects of well-characterized 20 and 40 nm silver nanoparticles (SNP). Similar gold nanoparticles served as control and proved inert for all endpoints tested. SNP induced a strong size-dependent cytotoxicity. Additionally, in the low concentration range (up to 10 µg/ml of SNP), the further differentiated cultures were more sensitive to SNP treatment. For detailed studies, we used low/medium dose concentrations (up to 20 µg/ml) and found strong oxidative stress responses. Reactive oxygen species (ROS) were detected along with the formation of protein carbonyls and the induction of heme oxygenase-1. We observed an acute calcium response, which clearly preceded oxidative stress responses. ROS formation was reduced by antioxidants, whereas the calcium response could not be alleviated by antioxidants. Finally, we looked into the responses of neurons and astrocytes separately. Astrocytes were much more vulnerable to SNP treatment compared with neurons. Consistently, SNP were mainly taken up by astrocytes and not by neurons. Immunofluorescence studies of mixed cell cultures indicated stronger effects on astrocyte morphology. Altogether, we can demonstrate strong effects of SNP associated with calcium dysregulation and ROS formation in primary neural cells, which were detectable already at moderate dosages. KW - Silver nanoparticles KW - Neurons KW - Oxidative stress KW - Protein carbonyls KW - Calcium KW - Reference material KW - Nanoparticle KW - Small-angle X-ray scattering KW - SAXS PY - 2012 DO - https://doi.org/10.1093/toxsci/kfs003 SN - 1096-6080 SN - 1096-0929 VL - 126 IS - 2 SP - 457 EP - 468 PB - Oxford University Press CY - Oxford AN - OPUS4-25633 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Meier, Klaus A1 - Wäthen, U. A1 - Kipphardt, Heinrich A1 - Lamberty, A. A1 - Robouch, P. T1 - The certification of the mass fraction of Cd, Cu, Fe, Pb, Sn and TI in four grades of unalloyed zinc intended for use in emission spectrometry - BCR-322R, BCR-323R, BCR-324R, BCR-325R, Project Report EUR 20267 EN PY - 2002 SN - 92-894-3706-5 SP - 1 EP - 55 PB - Office for Official Publications of the European Communities CY - Luxembourg AN - OPUS4-1606 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Uhlmann, E. A1 - Kropidlowski, K. A1 - Hinzmann, D. A1 - Meier, P. A1 - Prasol, L. A1 - Woydt, Mathias T1 - Drehen mit Niobcarbid-basierten Werkzeugen N2 - Niobcarbid (NbC) stellt aufgrund vorteilhafter Eigenschaften, wie zum Beispiel eine geringe Diffusionsneigung, in der Zerspannung eine vielversprechende Alternative zu konventionellen Schneidstoffen wie Wolframcarbid (WC) dar. Als Substitution der Hartstoff-Phase WC im Hartmetall wird NbC in der trockenen Drehbearbeitung von eisen-basierten Werkstoffen untersucht. Diesbezüglich wurden zwei NbC-Substrate mit WC hinsichtlich ihres Werkzeugverschleißes quantitativ verglichen. Im Gegensatz zu WC-Werkzeugen wird das Potential von NbC bei zunehmender Schnittgeschwindigkeit vc durch eine steigende Prozessstabilität deutlich. KW - Niobcarbid (NbC) KW - Werkzeug KW - Verschleiß PY - 2018 UR - https://www.werkstattstechnik.de/wt/article.php?data[article_id]=88885 SN - 1436-4980 SN - 1436-5006 VL - 108 IS - 1/2 SP - 18 EP - 25 PB - Springer-VDI-Verl. CY - Düsseldorf AN - OPUS4-44448 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Uhlmann, E. A1 - Hinzmann, D. A1 - Kropidlowski, K. A1 - Meier, P. A1 - Prasol, L. A1 - Woydt, Mathias T1 - Increased tool performance with niobium carbide based cutting materials in dry cylindrical turning N2 - In the present work it was shown that in contrast to WC tools NbC cutting tools show constant material removal VW at increased cutting speed vc combined with a higher process reliability. KW - Niobium carbide (NbC) KW - Tungsten carbide (WC) KW - Tool wear KW - Cylindrical turning PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-465968 DO - https://doi.org/10.1016/j.procir.2018.08.238 SN - 2212-8271 VL - 77 SP - 541 EP - 544 PB - Elsevier AN - OPUS4-46596 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Uhlmann, E. A1 - Hinzmann, D. A1 - Kropidlowski, K. A1 - Meier, P. A1 - Prasol, L. A1 - Woydt, Mathias T1 - Substitution of commercially coated tungsten carbide tools in dry cylindrical turning process by HiPIMS coated niobium carbide cutting inserts N2 - In this study the tool behavior of two NbC substrates, defined as NbC0.88-12Co and NbC1.0-12Ni4Mo4VC respectively, is compared to commercial, submicron grained WC-6Co tool material. KW - Turning KW - Tool KW - Coating KW - Physical vapor deposition (PVD) KW - Niobium carbide (NbC) PY - 2018 DO - https://doi.org/10.1016/j.surfcoat.2018.07.105 SN - 0257-8972 VL - 354 SP - 112 EP - 118 PB - Elsevier AN - OPUS4-45963 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Uhlmann, E. A1 - Meier, P. A1 - Hinzmann, D. A1 - Kropidlowski, K. A1 - Prasol, L. A1 - Woydt, Mathias T1 - Dry turning with niobium carbide based tools N2 - In the present work it was shown that Niobium carbide (NbC) offers a competitive profile compared to tungsten carbide (WC) as cutting material regarding ist wear resistance preferably in metal cutting processes. T2 - WORLDPM 2018 CY - Beijing, China DA - 16.09.2018 KW - Turning KW - Semi-finishing KW - Niobium carbide KW - Tungsten carbide KW - Iron-based alloys KW - Aluminum PY - 2018 SP - Part 5, 775 EP - 784 AN - OPUS4-46203 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Graf, P. A1 - Mantion, Alexandre A1 - Haase, A. A1 - Thünemann, Andreas A1 - Masic, A. A1 - Meier, W. A1 - Luch, A. A1 - Taubert, A. T1 - Silicification of peptide-coated silver nanoparticles - a biomimetic soft chemistry approach toward chiral hybrid core-shell materials N2 - Silica and silver nanoparticles are relevant materials for new applications in optics, medicine, and analytical chemistry. We have previously reported the synthesis of pH responsive, peptide-templated, chiral silver nanoparticles. The current report shows that peptide-stabilized nanoparticles can easily be coated with a silica shell by exploiting the ability of the peptide coating to hydrolyze silica precursors such as TEOS or TMOS. The resulting silica layer protects the nanoparticles from chemical etching, allows their inclusion in other materials, and renders them biocompatible. Using electron and atomic force microscopy, we show that the silica shell thickness and the particle aggregation can be controlled simply by the reaction time. Small-angle X ray scattering confirms the Ag/peptide@silica core–shell structure. UV–vis and circular dichroism spectroscopy prove the conservation of the silver nanoparticle chirality upon silicification. Biological tests show that the biocompatibility in simple bacterial systems is significantly improved once a silica layer is deposited on the silver particles. KW - Peptide-templated materials KW - Silver nanoparticles KW - Chiral nanoparticles KW - Ag/peptide@SiO2 nanostructures KW - Core-shell structures PY - 2011 DO - https://doi.org/10.1021/nn102969p SN - 1936-0851 VL - 5 IS - 2 SP - 820 EP - 833 PB - ACS Publ. CY - Washington, DC, USA AN - OPUS4-23207 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Haase, A. A1 - Arlinghaus, H. F. A1 - Tentschert, J. A1 - Jungnickel, H. A1 - Graf, P. A1 - Mantion, Alexandre A1 - Draude, F. A1 - Galla, S. A1 - Plendl, J. A1 - Goetz, M.E. A1 - Masic, A. A1 - Meier, W. A1 - Thünemann, Andreas A1 - Taubert, A. A1 - Luch, A. T1 - Application of laser postionization secondary neutral mass spectrometry / time-of-flight secondary ion mass spectrometry in nanotoxicology: Visualization of nanosilver in human macrophages and cellular responses N2 - Silver nanoparticles (SNP) are the subject of worldwide commercialization because of their antimicrobial effects. Yet only little data on their mode of action exist. Further, only few techniques allow for visualization and quantification of unlabeled nanoparticles inside cells. To study SNP of different sizes and coatings within human macrophages, we introduce a novel laser postionization secondary neutral mass spectrometry (Laser-SNMS) approach and prove this method superior to the widely applied confocal Raman and transmission electron microscopy. With time-of-flight secondary ion mass spectrometry (TOF-SIMS) we further demonstrate characteristic fingerprints in the lipid pattern of the cellular membrane indicative of oxidative stress and membrane fluidity changes. Increases of protein carbonyl and heme oxygenase-1 levels in treated cells confirm the presence of oxidative stress biochemically. Intriguingly, affected phagocytosis reveals as highly sensitive end point of SNP-mediated adversity in macrophages. The cellular responses monitored are hierarchically linked, but follow individual kinetics and are partially reversible. KW - Nanosilver KW - Laser-SNMS KW - TOF-SIMS KW - Confocal Raman microscopy KW - Oxidative stress KW - Protein carbonyls PY - 2011 DO - https://doi.org/10.1021/nn200163w SN - 1936-0851 VL - 5 IS - 4 SP - 3059 EP - 3068 PB - ACS Publ. CY - Washington, DC, USA AN - OPUS4-23656 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nehring, R. A1 - Palivan, C.G. A1 - Moreno-Flores, S. A1 - Mantion, Alexandre A1 - Tanner, P. A1 - Toca-Herrera, J.L. A1 - Thünemann, Andreas A1 - Meier, W. T1 - Protein decorated membranes by specific molecular interactions N2 - Here we characterize new metal-functionalized amphiphilic diblock copolymers, developed for both surface and solution molecular recognition applications. Polybutadiene-block-poly(ethylene oxide) copolymers functionalized with nitrilotriacetic acid and tris(nitrilotriacetic acid) were complexed with nickel(II) to obtain coordination sites for oligohistidine residues of model proteins. Mixtures of functionalized polymers with the respective non-functionalized block copolymers self-assemble in aqueous solution into vesicular structures with a controlled density of the metal end-groups on their surface. In solution, binding of His6-tagged green fluorescent protein (EGFP) and red fluorescent protein (RFP) to the vesicle surface was quantified by fluorescence correlation spectroscopy. Small-angle X-ray scattering indicates an increase of the membrane thickness by 2-3 nm upon protein binding. Block copolymer monolayers at the air-water interface and on solid support served as a model system to characterize the protein-decorated membranes by Brewster angle microscopy and AFM. High resolution AFM of solid-supported, hydrated monolayers indicates that the proteins form densely packed and partially ordered arrays with the cylindrically shaped EGFP molecules lying flat on the surface of the films. KW - Amphiphilic copolymer KW - Metal centers KW - His-tag proteins KW - Molecular recognition PY - 2010 DO - https://doi.org/10.1039/c002838j SN - 1744-683X VL - 6 SP - 2815 EP - 2824 PB - RSC Publ. CY - Cambridge AN - OPUS4-21564 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Haase, A. A1 - Mantion, Alexandre A1 - Graf, P. A1 - Plendl, J. A1 - Thünemann, Andreas A1 - Meier, W. A1 - Taubert, A. A1 - Luch, A. T1 - A novel type of silver nanoparticles and their advantages in toxicity testing in cell culture systems N2 - Silver nanoparticles (SNPs) are among the most commercialized nanoparticles worldwide. Often SNP are used because of their antibacterial properties. Besides that they possess unique optic and catalytic features, making them highly interesting for the creation of novel and advanced functional materials. Despite its widespread use only little data exist in terms of possible adverse effects of SNP on human health. Conventional synthesis routes usually yield products of varying quality and property. It thus may become puzzling to compare biological data from different studies due to the great variety in sizes, coatings or shapes of the particles applied. Here, we applied a novel synthesis approach to obtain SNP of well-defined colloidal and structural properties. Being stabilized by a covalently linked small peptide, these particles are nicely homogenous, with narrow size distribution, and form monodisperse suspensions in aqueous solutions. We applied these peptide- coated SNP in two different sizes of 20 or 40 nm (Ag20Pep and Ag40Pep) and analyzed responses of THP- 1-derived human macrophages while being exposed against these particles. Gold nanoparticles of similar size and coating (Au20Pep) were used for comparison. The cytotoxicity of particles was assessed by WST-1 and LDH assays, and the uptake into the cells was confirmed via transmission electron microscopy. In summary, our data demonstrate that this novel type of SNP is well suited to serve as model system for nanoparticles to be tested in toxicological studies in vitro. KW - Silver nanoparticles KW - Peptide coating KW - Nanotoxicity PY - 2012 DO - https://doi.org/10.1007/s00204-012-0836-0 SN - 0340-5761 SN - 1432-0738 VL - 86 IS - 7 SP - 1089 EP - 1098 PB - Springer CY - Berlin ; Heidelberg [u.a.] AN - OPUS4-26269 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Peters, R. A1 - Elbers, I. A1 - Undas, A. A1 - Sijtsma, E. A1 - Briffa, S. A1 - Carnell-Morris, P. A1 - Siupa, A. A1 - Yoon, T.-H. A1 - Burr, L. A1 - Schmid, D. A1 - Tentschert, J. A1 - Hachenberger, Y. A1 - Jungnickel, H. A1 - Luch, A. A1 - Meier, F. A1 - Kocic, J. A1 - Kim, J. A1 - Park, B. C. A1 - Hardy, B. A1 - Johnston, C. A1 - Jurkschat, K. A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan A1 - Lynch, I. A1 - Valsami-Jones, E. T1 - Benchmarking the ACEnano toolbox for characterisation of nanoparticle size and concentration by interlaboratory comparisons N2 - ACEnano is an EU-funded project which aims at developing, optimising and validating methods for the detection and characterisation of nanomaterials (NMs) in increasingly complex matrices to improve confidence in the results and support their use in regulation. Within this project, several interlaboratory comparisons (ILCs) for the determination of particle size and concentration have been organised to benchmark existing analytical methods. In this paper the results of a number of these ILCs for the characterisation of NMs are presented and discussed. The results of the analyses of pristine well-defined particles such as 60 nm Au NMs in a simple aqueous suspension showed that laboratories are well capable of determining the sizes of these particles. The analysis of particles in complex matrices or formulations such as consumer products resulted in larger variations in particle sizes within technologies and clear differences in capability between techniques. Sunscreen lotion sample analysis by laboratories using spICP-MS and TEM/SEM identified and confirmed the TiO2 particles as being nanoscale and compliant with the EU definition of an NM for regulatory purposes. In a toothpaste sample orthogonal results by PTA, spICP-MS and TEM/SEM agreed and stated the TiO2 particles as not fitting the EU definition of an NM. In general, from the results of these ILCs we conclude that laboratories are well capable of determining particle sizes of NM, even in fairly complex formulations. KW - Nanomaterials KW - Benchmarking KW - Inter-laboratory comparison KW - ACEnano KW - Characterisation KW - Size KW - Concentration PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-531852 DO - https://doi.org/10.3390/molecules26175315 SN - 1420-3049 VL - 26 IS - 17 SP - 1 EP - 23 PB - MDPI CY - Basel AN - OPUS4-53185 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Peters, R. A1 - Elbers, I. A1 - Undas, A. A1 - Sijtsma, E. A1 - Briffa, S. A1 - Carnell-Morris, P. A1 - Siupa, A. A1 - Yoon, T.-H. A1 - Burr, L. A1 - Schmid, D. A1 - Tentschert, J. A1 - Hachenberger, Y. A1 - Jungnickel, H. A1 - Luch, A. A1 - Meier, F. A1 - Kocic, J. A1 - Kim, J. A1 - Park, B. C. A1 - Hardy, B. A1 - Johnston, C. A1 - Jurkschat, K. A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan A1 - Lynch, I. A1 - Valsami-Jones, E. T1 - Correction: Peters et al. Benchmarking the ACEnano Toolbox for Characterisation of Nanoparticle Size and Concentration by Interlaboratory Comparisons. Molecules 2021, 26, 5315 N2 - This is a corrigendum to the original article "Benchmarking the ACEnano toolbox for characterisation of nanoparticle size and concentration by interlaboratory comparisons" that was published in the journal "Molecules", vol. 26 (2021), no. 17, article 5315. PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-554381 DO - https://doi.org/10.3390/molecules27154849 VL - 27 IS - 4849 SP - 1 EP - 3 PB - MDPI CY - Basel AN - OPUS4-55438 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -