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 - Simon, Fabian A1 - Gehrenkemper, Lennart A1 - von der Au, Marcus A1 - Wittwer, Phillip A1 - Roesch, Philipp A1 - Pfeifer, Jens A1 - Cossmer, Antje A1 - Meermann, Björn T1 - A fast and simple PFAS extraction method utilizing HR–CS–GFMAS for soil samples N2 - Here, we describe an optimized fast and simple extraction method for the determination of per- and polyfluorinated alkyl substances (PFASs) in soils utilizing high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR–CS–GFMAS). To omit the bias of the solid phase extraction (SPE) step commonly used during the analysis of extractable organically bound fluorine (EOF) we optimized a fast and simple SPE-free extraction method. The developed extraction method consists of a liquid-solid extraction using acidified methanol without any additional SPE. Four extraction steps were representative to determine a high proportion of the EOF (>80% of eight extractions). Comparison of the optimized method with and without an additional SPE clean-up step revealed a drastic underestimation of EOF concentrations using SPE. Differences of up to 94% were observed which were not explainable by coextracted inorganic fluoride. Therefore, not only a more accurate but also a more economic as well as ecologic method (bypassing of unnecessary SPE) was developed. The procedural limit of quantification (LOQ) of the developed method was 10.30 μg/kg which was sufficient for quantifying EOF concentrations in all tested samples. For future PFAS monitoring and potential regulative decisions the herein presented optimized extraction method can offer a valuable contribution. KW - Per- and polyfluorinated alkly substances (PFASs) KW - High resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) KW - Soils KW - Solid phase extraction (SPE) KW - Extractable organically bound fluorine (EOF) KW - Solid-liquid extraction PY - 2022 DO - https://doi.org/10.1016/j.chemosphere.2022.133922 VL - 295 SP - 1 EP - 9 PB - Elsevier Ltd. AN - OPUS4-54359 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Daly, H.C A1 - Matikonda, S.S A1 - Steffens, H.C A1 - Rühle, Bastian A1 - Resch-Genger, Ute A1 - Ivanic, J. A1 - Schermann, M.J T1 - Daly_Photochem Photobiol 2021_Ketone Incorporation Extends the Emission Properties of the Xanthene Scaffold N2 - Imaging in the shortwave-infrared region (SWIR, λ = 1000–2500 nm) has the potential to enable deep tissue imaging with high resolution. Critical to the development of these Methods is the identification of low molecular weight, biologically compatible fluorescent probes that emit beyond 1000 nm. Exchanging the bridging oxygen atom on the xanthene scaffold (C10’ position) with electron withdrawing groups has been shown to lead to significant redshifts in absorbance and emission. Guided by quantum chemistry computational modeling studies, we investigated the installation of a Ketone bridge at the C10’ position. This simple modification extends the absorbance maxima to 860 nm and the emission beyond 1000 nm, albeit with reduced photon output. Overall, These studies demonstrate that broadly applied xanthene dyes can be extended into the SWIR range. KW - Flourescence KW - Optical probe KW - Dye KW - Photophysics KW - Quantum yield KW - Mechanism KW - NIR KW - SWIR KW - Imaging KW - Reliability KW - Method KW - Quality assurance PY - 2021 DO - https://doi.org/10.1111/php.13544 SN - 1751-1097 VL - 98 IS - 2 SP - 325 EP - 333 PB - Wiley Online Library AN - OPUS4-54080 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Drescher, D. A1 - Büchner, T. A1 - Schrade, P. A1 - Traub, Heike A1 - Werner, S. A1 - Guttmann, P. A1 - Bachmann, S. A1 - Kneipp, J. T1 - Influence of Nuclear Localization Sequences on the Intracellular Fate of Gold Nanoparticles N2 - Directing nanoparticles to the nucleus by attachment of nuclear localization sequences (NLS) is an aim in many applications. Gold nanoparticles modified with two different NLS were studied while crossing barriers of intact cells, including uptake, endosomal escape, and nuclear translocation. By imaging of the nanoparticles and by characterization of their molecular interactions with surface-enhanced Raman scattering (SERS), it is shown that nuclear translocation strongly depends on the particular incubation conditions. After an 1 h of incubation followed by a 24 h chase time, 14 nm gold particles carrying an adenoviral NLS are localized in endosomes, in the cytoplasm, and in the nucleus of fibroblast cells. In contrast, the cells display no nanoparticles in the cytoplasm or nucleus when continuously incubated with the nanoparticles for 24 h. The ultrastructural and spectroscopic data indicate different processing of NLS-functionalized particles in endosomes compared to unmodified particles. NLS functionalized nanoparticles form larger intraendosomal aggregates than unmodified gold nanoparticles. SERS spectra of cells with NLS-functionalized gold nanoparticles contain bands assigned to DNA and were clearly different from those with unmodified gold nanoparticles. The different processing in the presence of an NLS is influenced by a continuous exposure of the cells to nanoparticles and an ongoing nanoparticle uptake. This is supported by mass-spectrometry-based quantification that indicates enhanced uptake of NLS-functionalized nanoparticles compared to unmodified particles under the same conditions. The results contribute to the optimization of nanoparticle analysis in cells in a variety of applications, e.g., in theranostics, biotechnology, and bioanalytics. KW - Nanoparticle KW - Laser ablation KW - SERS KW - ICP-MS PY - 2021 DO - https://doi.org/10.1021/acsnano.1c04925 SN - 1936-086X VL - 15 IS - 9 SP - 14838 EP - 14849 PB - American Chemical Society AN - OPUS4-54047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sommerfeld, Thomas A1 - Jung, Christian A1 - Riedel, Juliane A1 - Mauch, Tatjana A1 - Sauer, Andreas A1 - Koch, Matthias T1 - Development of a certified reference material for the determination of polycyclic aromatic hydrocarbons (PAHs) in rubber toy N2 - Polycyclic aromatic hydrocarbons (PAHs) are a large group of priority organic pollutants, which contaminate environmental compartments, food, and consumer products as well. Due to their frequent occurrence associated with elevated Levels of PAHs, plastic and rubber parts of consumer products and toys are particular sources of exposure. Although European maximum levels exist for eight carcinogenic PAHs in consumer products and toys according to REACH Regulation (EC) No. 1907/2006, certified reference materials (CRM) are still not available. To overcome this lack, the first CRM for the determination of PAHs in rubber toys (BAM-B001) was developed according to the requirements of ISO Guide 35. The whole process of CRM development including preparation, homogeneity and stability studies, and value assignment is presented. The assignment of the certified mass fractions was based upon in-house study at BAM using stable isotope Dilution analysis (SIDA) gas chromatography mass spectrometry (GC–MS). The obtained values were confirmed by the results of two interlaboratory comparison (ILC) studies with more than 50 expert laboratories from Germany and China. The mass fractions of 14 PAHs including all REACH and GS mark regulated compounds were certified ranging between 0.2 and 15.4 mg/ kg accompanied by expanded uncertainties (coverage factor k = 2). In addition, informative values were determined for 4 PAHs, mainly due to higher uncertainties and/or lack of ILC data for confirmation. BAM-B001 is intended for analytical quality control particularly based on the AfPS GS 2019:01 PAK method and contributes to improve the chemical safety of consumer products including toys. KW - PAHs KW - Consumer Products KW - Toys KW - Chemical Safety KW - Certified reference material KW - Quality assurance PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-539920 DO - https://doi.org/10.1007/s00216-021-03796-5 VL - 414 IS - 15 SP - 4369 EP - 4378 PB - Springer AN - OPUS4-53992 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sebald, M. A1 - Gebauer, J. A1 - Koch, Matthias T1 - Diastereoselective synthesis of (±)-trichodiene and (±)-trichodiene-D3 as analytical standards for the on-site quantification of trichothecenes N2 - The ubiquitous Fusarium genus is responsible for the spoilage of vast amounts of cereals and fruits. Besides the economic damage, the danger to human and animal health by the concomitant exposure to mycotoxins represents a serious problem. A large number of Fusarium species produce a variety of different mycotoxins of which the class of trichothecenes are of particular importance due to their toxicity. Being identified as the common volatile precursor during the biosynthesis of trichothecenes, (−)-trichodiene (TD) is considered to be a biomarker for the respective mycotoxin content in food samples. We postulated that the development of a non-invasive, on-site GC-IMS method for the quantification of (−)-trichodiene supplemented with a stationary SIDA headspace GC-MS reference method would allow circumventing the laborious and expensive analyses of individual trichothecenes in large cereal samples. In this work we present the syntheses of the required native calibration standard and an isotope labeled (TD-D3) internal standard. KW - Mycotoxins KW - Volatile marker KW - Food analysis KW - Screening method KW - Mobile analysis PY - 2021 DO - https://doi.org/10.1039/d1ob01778k VL - 19 IS - 45 SP - 9872 EP - 9879 PB - RSC AN - OPUS4-53993 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sebald, M. A1 - Gebauer, J. A1 - Koch, Matthias T1 - Concise Synthesis of Alternariol and Alternariol-9-monomethyl ether as well as their D3-Isotopologues N2 - Abstract Alternariol (AOH) and alternariol-9-monomethyl ether (AME) are two secondary metabolites of Alternaria fungi which can be found in various foodstuff like tomatoes, nuts, and grains. Due to their toxicity and potential mutagenic activity the need for the development of high-throughput methods for the supervision of AOH- and AME-levels is of increasing interest. As the availability of both native and labeled AOH and AME analytical standards is very limited we herein wish to present a novel concise approach towards their synthesis employing a ruthenium-catalyzed ortho-arylation as the key step. Finally, we demonstrate their suitability as internal standards in stable-isotope dilution assay (SIDA)-HPLC-MS/MS analysis commonly used for the quantification of the natural products in food and feed. KW - Mycotoxins KW - Food Analysis KW - Emerging contaminants PY - 2021 DO - https://doi.org/10.1055/a-1698-8328 SN - 0039-7881 VL - 54 IS - 19 SP - 4285 EP - 4293 PB - Thieme AN - OPUS4-53994 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Villajos Collado, José Antonio T1 - Experimental volumetric hydrogen uptake determination at 77 K of commercially available metal-organic framework materials N2 - Storage is still limiting the implementation of hydrogen as an energy carrier to integrate the intermittent operation of renewable energy sources. Among different solutions to the currently used compressed or liquified hydrogen systems, physical adsorption at cryogenic temperature in porous materials is an attractive alternative due to its fast and reversible operation and the resulting reduction in storage pressure. The feasibility of cryoadsorption for hydrogen storage depends mainly on the performance of the used materials for the specific application, where metal-organic frameworks or MOFs are remarkable candidates. In this work, gravimetric and volumetric hydrogen uptakes at 77 K and up to 100 bar of commercially available MOFs were measured since these materials are made from relatively cheap and accessible building blocks. These materials also show relatively high porous properties and are currently near to large-scale production. The measuring device was calibrated at different room temperatures to calculate an average correction factor and standard deviation so that the correction deviation is included in the measurement error for better comparability with different measurements. The influence of measurement conditions was also studied, concluding that the available adsorbing area of material and the occupied volume of the sample are the most critical factors for a reproducible measurement, apart from the samples’ preparation before measurement. Finally, the actual volumetric storage density of the used powders was calculated by directly measuring their volume in the analysis cell, comparing that value with the maximum volumetric uptake considering the measured density of crystals. From this selection of commercial MOFs, the materials HKUST-1, PCN-250(Fe), MOF-177, and MOF-5 show true potential to fulfill a volumetric requirement of 40 g·L−1 on a material basis for hydrogen storage systems without further packing of the powders. KW - Hydrogen adsorption KW - Commercial metal-organic frameworks KW - Hydrogen uptake reproducibility KW - Volumetric uptake KW - Packing density PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542215 DO - https://doi.org/10.3390/c8010005 SN - 2311-5629 VL - 8 IS - 1 SP - 1 EP - 14 PB - MDPI CY - Basel AN - OPUS4-54221 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kazlagic, Anera A1 - Russo, Francesco A1 - Vogl, Jochen A1 - Sturm, Patrick A1 - Stephan, D. A1 - Gluth, Gregor ED - Resch-Genger, Ute ED - Koch, Matthias ED - Meermann, Björn ED - Weller, Michael G. T1 - Development of a sample preparation procedure for Sr isotope analysis of Portland cements N2 - The 87Sr/86Sr isotope ratio can, in principle, be used for provenancing of cement. However, while commercial cements consist of multiple components, no detailed investigation into their individual 87Sr/86Sr isotope ratios or their influence on the integral 87Sr/86Sr isotope ratio of the resulting cement was conducted previously. Therefore, the present study aimed at determining and comparing the conventional 87Sr/86Sr isotope ratios of a diverse set of Portland cements and their corresponding Portland clinkers, the major component of these cements. Two approaches to remove the additives from the cements, i.e. to measure the conventional 87Sr/86Sr isotopic fingerprint of the clinker only, were tested, namely, treatment with a potassium hydroxide/sucrose solution and sieving on a 11-µm sieve. Dissolution in concentrated hydrochloric acid/nitric acid and in diluted nitric acid was employed to determine the 87Sr/86Sr isotope ratios of the cements and the individual clinkers. The aim was to find the most appropriate sample preparation procedure for cement provenancing, and the selection was realised by comparing the 87Sr/86Sr isotope ratios of differently treated cements with those of the corresponding clinkers. None of the methods to separate the clinkers from the cements proved to be satisfactory. However, it was found that the 87Sr/86Sr isotope ratios of clinker and cement generally corresponded, meaning that the latter can be used as a proxy for the clinker 87Sr/86Sr isotope ratio. Finally, the concentrated hydrochloric acid/nitric acid dissolution method was found to be the most suitable sample preparation method for the cements; it is thus recommended for 87Sr/86Sr isotope analyses for cement provenancing. KW - Cement KW - Provenancing KW - Sr isotopes KW - Portland clinker KW - Dissolution PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542239 DO - https://doi.org/10.1007/s00216-021-03821-7 SN - 1618-2642 SN - 1618-2650 VL - 414 IS - 15 (Topical collection: Analytical methods and applications in the materials and life sciences) SP - 4379 EP - 4389 PB - Springer CY - Berlin AN - OPUS4-54223 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dariz, P. A1 - Wortmann, U. G. A1 - Vogl, Jochen A1 - Schmid, Thomas T1 - Beautiful Pietàs in South Tyrol (Northern Italy): local or imported works of art? N2 - The study, dedicated to Beautiful Pietàs conserved in South Tyrol (Northern Italy), aims to establish, for the first time, a connection between Austroalpine raw materials and the high-fired gypsum mortars constituting the Gothic figure groups in question. The origin and chronology of this stylistically and qualitatively differing ensemble have been subject of art historical debate for nearly a century. The discourse is dominated by three main hypotheses: itinerary of an Austrian artist versus itinerary of the work of art created in an artist’s workshop in Austria versus itinerary of the stylistic vocabulary via graphical or three-dimensional models. The comparison of the δ34S values and the 87Sr/86Sr ratios of the gypsum mortars and Austroalpine sulphate deposits (in a compilation of own reference samples and literature data) points to the exploitation of sediments in the Salzkammergut and possibly also in the evaporite district of the Eastern Calcareous Alps, thus evidencing the import of the sculptures and not the activities of local South Tyrolean or itinerant artists. Two geochronological units are distinguishable: The Pietà in the Church St. Martin in Göflan can be assigned to Upper Permian raw material, whereas the metrologically consistent sculptures in the Church of Our Lady of the Benedictine Abbey Marienberg and in the Chapel St. Ann in Mölten correlate with deposits of the Early Triassic (or the Lower-Middle Triassic transition). The medieval gypsum mortars also differ in their mineralogical characteristics, i.e. in their geologically related minor components, as in the first case, characterised by a significant proportion of primary anhydrite, natural carbonate impurities mainly consist of calcite (partly converted to lime-lump-like aggregates), whereas in the second group dolomite (or rather its hydration products after pyrometamorphic decomposition) predominates, accompanied by celestine, quartz and potassium feldspar. The Pietà in the Cathedral Maria Himmelfahrt in Bozen turned out to be made of Breitenbrunn calcareous sandstone (Leitha Mountains, Burgenland, Austria), which is why the sample is not considered in the geochemical analysis. KW - High-fired gypsum mortar KW - Sulphur isotope KW - Strontium isotope KW - Polarised light microscopy KW - Raman microspectroscopy PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545610 DO - https://doi.org/10.1186/s40494-022-00678-6 SN - 2050-7445 VL - 10 IS - 1 SP - 1 EP - 17 PB - Springer Nature AN - OPUS4-54561 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -