TY - JOUR A1 - Von der Au, M. A1 - Borovinskaya, O. A1 - Büchel, C. A1 - Meermann, Björn T1 - Der Fingerabdruck der Kieselalge N2 - Elementanalytische Verfahren werden heute zu mehr eingesetzt als bloß zur Bestimmung von Metallgesamtgehalten in diversen Probenmatrizes. Sie stellen heute ein wichtiges Werkzeug zur Beantwortung lebenswissenschaftlicher Fragen aus Umwelt, Medizin und Biologie dar. In der vorliegenden Arbeit kommt die single-cell-ICP-Flugzeitmassenspektrometrie (single-cell-ICP-TOF-MS) zur Multielementanalytik in einzelnen Kieselalgen (Diatomeen) zum Einsatz und wird zukünftig ein wichtiges Werkzeug z.B. bei der Beantwortung ökotoxikologischer Fragestellung sein. KW - Diatomeenanalytik KW - Single cell-ICP-ToF-MS KW - Multielementanalytik in kurzen transienten Signalen PY - 2019 UR - https://q-more.chemie.de/q-more-artikel/299/der-fingerabdruck-der-kieselalge.html SP - 1 EP - 3 PB - LUMITOS AN - OPUS4-49749 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Von der Au, M. A1 - Meermann, Björn T1 - Screening von Organofluorverbindungen im Oberflächenwasser N2 - Organofluorverbindungen kommen in vielen Bereichen zum Einsatz und gelangen in die aquatische Umwelt. Die Belastungssituation der Gewässer ist bisher wenig untersucht – hier kommt die HR-CS GF MAS als leistungsstarkes Screeningtool zum Einsatz. KW - HR-CS-GFMAS KW - Extrahierbar organisch gebundenes Fluor (EOF) KW - Oberflächengewässer PY - 2019 UR - https://analytik.news/Fachartikel/Volltext/bam5.pdf SP - 1 EP - 3 PB - Dr. Beyer Internet-Beratung AN - OPUS4-49750 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - von der Au, Marcus A1 - Borovinskaya, O. A1 - Flamigni, L. A1 - Kuhlmeier, K. A1 - Büchel, C. A1 - Meermann, Björn T1 - Single cell-inductively coupled plasma-time of flight-mass spectrometry approach for ecotoxicological testing N2 - Diatoms play a key role in assessing the eco-toxicology of metals and are already part of several national and international guidelines and regulations. Data on metal uptake and its correlation with a natural metal composition of the diatoms are mostly lacking on a cellular basis - mainly due to the lack of a suitable method on both the preparation and detection side. Therefore, within this work a fully automated approach based on the on-line coupling of a high performance liquid chromatograph (HPLC) and an inductively coupled plasma-time of flight-mass spectrometer (ICP-ToF-MS) was applied to analyze single cells of the alga Cyclotella meneghiniana multi-elementally in order to provide a deeper insight into the metal composition and its response to environmental stress. Multi-elemental analysis in single diatoms also enables assessment of combined toxicity of a set of metals. A set of four fingerprint elements, characteristically for diatoms (Mg, P, Si, Fe), were identified and hence the investigation of environmental stress onto the cells was enabled by performing incubation experiments with environmentally relevant toxic elements. It could be shown at moderate environmental stress caused by increasing the metal concentration in the medium (zinc) that the fingerprint element concentrations remained stable and thus the suitability of the selected elements for algae tracing was demonstrated. With regard to further ecotoxicological assessments, a multivariate approach was successfully applied allowing for cell classification upon different incubation concentration levels. This multivariate approach also facilitated an effective identification of three different diatom species (Cyclotella meneghiniana, Thalassiosira weissflogii and Thalassiosira pseudonana). KW - ICP-TOF-MS KW - Ecotoxicological Testing KW - Diatoms PY - 2020 DO - https://doi.org/10.1016/j.algal.2020.101964 VL - 49 SP - 101964 PB - Elsevier B.V. AN - OPUS4-50875 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - von der Au, Marcus A1 - Faßbender, Sebastian A1 - Chronakis, Michail A1 - Vogl, Jochen A1 - Meermann, Björn T1 - Size determination of nanoparticles by ICP-ToF-MS using isotope dilution in microdroplets N2 - Within this work, the combination of a microdroplet generator and an ICP-ToF-MS for nanoparticle analysis is presented. For the size determination of platinum nanoparticles an on-line isotope dilution analysis approach was developed. The 194Pt/195Pt isotopic ratio was used for the characterization of the particles, while the 182W/183W isotopic ratio was monitored simultaneously for mass bias correction. The on-line ID-MDG-sp-ICP-ToF-MS approach was deployed for the size determination of three platinum nanoparticle samples (50 nm, 63 nm, 70 nm); for validation, complementary size characterization techniques (sp-ICP-ToF-MS and TEM) were used. The robustness of this technique was evidenced, by using sodium chloride concentrations up to 100 mg L−1 as a matrix component. Our new on-line ID MDG-sp-ICP-ToF-MS approach is a promising tool for the fast and reliable determination of nanoparticles' size in severe matrix concentrations, e.g., environmental samples. KW - ICP-ToF-MS KW - Nanoparticles KW - Isotope Dilution PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552727 DO - https://doi.org/10.1039/D2JA00072E SN - 0267-9477 VL - 37 IS - 6 SP - 1203 EP - 1207 PB - Royal Society of Chemistry AN - OPUS4-55272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - von der Au, Marcus A1 - Karbach, H. A1 - Bell, A. M. A1 - Bauer, O. B. A1 - Karst, U. A1 - Meermann, Björn T1 - Determination of metal uptake in single organisms, Corophiumvolutator, via complementary electrothermal vaporization/inductively coupled plasma mass spectrometry and laserablation/inductively coupled plasma mass spectrometry N2 - Rationale: (Eco-)toxicological effects are mostly derived empirically and are notcorrelated with metal uptake. Furthermore, if the metal content is determined,mostly bulk analysis of the whole organism population is conducted; thus, biologicalvariability is completely disregarded, and this may lead to misleading results. Toovercome this issue, we compared two different solid sampling techniques for theanalysis of single organisms.Methods: In this study, complementary electrothermal vaporization/inductivelycoupled plasma mass spectrometry (ETV/ICP-MS) , laser ablation/inductivelycoupled plasma mass spectrometry (LA/ICP-MS)-based methods for the analysisof individual organisms were developed and the results obtained were comparedwith the concentrations obtained after digestion and measured using ICP-MS.For this purpose, a common (eco-)toxicological test organism, the mud shrimpCorophium volutator, was selected. As proof-of-concept application, these organismswere incubated with environmentally relevant metals from galvanic anodes, whichare often used for protection against metal corrosion in, for example, offshorewind farms.Results: The bulk analysis revealed that large quantities of the incubated elementswere detectable. Using the ETV/ICP-MS method, we could identify a highbiovariability within the population of organisms tested. Using the LA/ICP-MSmethod, it could be determined that the large quantities of the elements detectedwere due to adsorption of the metals and not due to uptake, which correlates wellwith the absence of (eco-)toxicological effects.Conclusions: The results obtained imply the efficiency of complementary methods toexplain the absence or presence of (eco-)toxicological effects. In particular, methodsthat allow for single-organism analysis or provide even a spatial resolution supportthe interpretation of ecotoxicological findings. KW - ICP-MS KW - Metal toxicity KW - Metal uptake KW - Corophium volutator KW - Seawater PY - 2021 DO - https://doi.org/10.1002/rcm.8953 VL - 35 IS - 2 SP - e8953 AN - OPUS4-52077 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - von der Au, Marcus A1 - Schwinn, M. A1 - Kuhlmeier, K. A1 - Büchel, C. A1 - Meermann, Björn T1 - Development of an automated on-line purification HPLC single cell-ICP-MS approach for fast diatom analysis N2 - The most challenging part in performing a single cell ICP-MS (sc-ICP-MS) approach is the sample preparation, in particular the reduction of the ionic background. This step is, in many cases, time-consuming and required for each sample separately. Furthermore, sc-ICP-MS measurements are mostly carried out "manually", given the fact that present systems are not allowing for an automated change of samples. Thus, within this work, we developed an approach based on a HPLC system coupled on-line with sc-ICP-MS via a set of switching valves as well as an in-line filter for automated cell washing. This set-up enables the ionic background removal as well as analysis of single cells completely automated without any manual sample pretreatment. Our approach was applied for the analysis of the single celled diatom species Cyclotella meneghiniana, a marine diatom species, on the basis of Mg24 and facilitates testing in 11 min per sample, requiring only around 10,000 cells in a volume of 10 µL and approx. 10 mL of a 5% MeOH/95% deionized water (v/v) mixture. Even at extremely saline culturing media concentrations (up to 1000 mg L-1 magnesium) our on-line approach worked sufficiently allowing for distinction of ionic and particulate fractions. Furthermore, a set of diatom samples was analyzed completely automated without the need for changing samples manually. So, utilizing this approach enables analyzing a high quantity of samples in a short time and therefore in future the investigation of ecotoxicological effects is simplified for example in terms of metal accumulation by taking biovariability into account. KW - Single cell-ICP-MS KW - Diatoms KW - Ecotoxicology testing KW - Automated system PY - 2019 DO - https://doi.org/10.1016/j.aca.2019.05.045 SN - 1873-4324 VL - 1077 SP - 87 EP - 94 PB - Elsevier AN - OPUS4-48567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Völzke, Jule L. A1 - Smatty, Sarah A1 - Döring, Sarah A1 - Ewald, Shireen A1 - Oelze, Marcus A1 - Fratzke, Franziska A1 - Flemig, Sabine A1 - Konthur, Zoltán A1 - Weller, Michael G. T1 - Efficient Purification of Polyhistidine-Tagged Recombinant Proteins Using Functionalized Corundum Particles N2 - Immobilized metal affinity chromatography (IMAC) is a widely used technique for purifying polyhistidine-tagged recombinant proteins. However, it often has practical limitations that require complex optimizations and additional steps for purification. In this study, we introduce functionalized corundum particles as a novel, efficient, and economical method for purifying recombinant proteins in a column-free format. The corundum surface is modified with amino silane APTES, followed by EDTA dianhydride, and then loaded with nickel ions. We used the Kaiser test to monitor the modification process and ICP-MS to quantify the metal-binding capacity. To evaluate the system, we used His-tagged protein A/G (PAG) mixed with bovine serum albumin (BSA). The corundum particles exhibited a binding capacity of approximately 3 mg of protein per gram of corundum or 2.4 mg per 1 mL of corundum suspension. We also examined cytoplasm obtained from different E. coli strains as an example of a complex matrix. Varying the imidazole concentration in the loading and washing buffers showed that higher concentrations during loading improved purity. Even with sample volumes as large as one liter, we successfully isolated recombinant proteins down to a concentration of 1 µg/mL. We found higher purity levels with corundum when comparing the corundum material to standard Ni–NTA agarose beads. We successfully purified His6-MBP-mSA2, a fusion protein comprising monomeric streptavidin and maltose-binding protein, from E. coli cytoplasm, demonstrating the method's applicability. We also purified SARS-CoV-2-S-RBD-His8 expressed in human Expi293F cells, confirming its suitability for mammalian cell culture supernatants. The material cost of the nickel-loaded corundum material (without regeneration) is estimated to be less than 30 cents per gram of functionalized support or 10 cents per milligram of isolated protein. Another advantage of this system is the exceptional physical and chemical stability of corundum particles. Overall, we have demonstrated that this novel material offers an efficient, robust, and cost-effective purification platform for His-tagged proteins, even in challenging, complex matrices and large sample volumes with low product concentrations. This method has potential applications in both small laboratories and large-scale industrial settings. N2 - Die immobilisierte Metallaffinitätschromatographie (IMAC) ist eine weit verbreitete Technik zur Reinigung von rekombinanten Proteinen mit Polyhistidin-Markierung. Sie hat jedoch oft praktische Einschränkungen, die komplexe Optimierungen und zusätzliche Schritte für die Aufreinigung erfordern. In dieser Studie stellen wir funktionalisierte Korundpartikel als neuartige, effiziente und wirtschaftliche Methode zur Reinigung rekombinanter Proteine in einem säulenfreien Format vor. Die Korundoberfläche wird mit dem Aminosilan APTES und anschließend mit EDTA-Dianhydrid modifiziert und dann mit Nickelionen beladen. Wir haben den Kaiser-Test zur Überwachung des Modifizierungsprozesses und ICP-MS zur Quantifizierung der Metallbindungskapazität verwendet. Zur Charakterisierung des Systems verwendeten wir His-markiertes Protein A/G (PAG) in Kombination mit Rinderserumalbumin (BSA). Die Korundpartikel wiesen eine Bindungskapazität von etwa 3 mg Protein pro Gramm Korund oder 2,4 mg pro 1 ml Korundsuspension auf. Als Beispiel für eine komplexe Matrix untersuchten wir auch Zytoplasma, das aus verschiedenen E. coli-Stämmen gewonnen wurde. Die Variation der Imidazolkonzentration in den Lade- und Waschpuffern zeigte, dass höhere Konzentrationen beim Laden die Reinheit verbesserten. Selbst bei einem Probenvolumen von bis zu einem Liter konnten wir rekombinante Proteine von 1 µg/mL isolieren. Beim Vergleich des Korundmaterials mit Standard-Ni-NTA-Agarose-Beads stellten wir einen höheren Reinheitsgrad mit Korund fest. Wir reinigten erfolgreich His6-MBP-mSA2 aus E. coli-Zytoplasma, ein Fusionsprotein, das aus monomerem Streptavidin und Maltose-bindendem Protein besteht. Wir reinigten auch SARS-CoV-2-S-RBD-His8, das in humanen Expi293F-Zellen exprimiert wurde, und bestätigten damit die Eignung des Materials für Zellkulturüberstände von Säugetieren. Die Materialkosten für nickelbeladenen Korund (ohne Regenerierung) werden auf weniger als 30 Cent pro Gramm funktionalisierten Trägers oder 10 Cent pro Milligramm isolierten Proteins geschätzt. Ein weiterer Vorteil dieses Systems ist die außergewöhnliche physikalische und chemische Stabilität der Korundpartikel. Insgesamt haben wir gezeigt, dass dieses neuartige Material eine effiziente, robuste und kostengünstige Reinigungsplattform für His-markierte Proteine bietet, selbst bei schwierigen, komplexen Matrices und großen Probenmengen mit niedrigen Produktkonzentrationen. Diese Methode könnte sowohl in kleinen Labors als auch in der Großindustrie eingesetzt werden. KW - Aluminum oxide KW - Sapphire KW - Ethylenediaminetetraacetic acid KW - Nickel chelate KW - EDTAD KW - HexaHis-Tag KW - His6 KW - 6xHis KW - His8 KW - Bioseparation KW - IMAC purification KW - Immunocapture KW - Affinity chromatography KW - Carrier KW - Nickel KW - Recombinant protein KW - Escherichia coli KW - Bacterial lysates KW - Cytoplasm KW - Polishing KW - Downstream processing PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575672 DO - https://doi.org/10.3390/biotech12020031 VL - 12 IS - 2 SP - 1 EP - 18 PB - MDPI CY - Basel, Schweiz AN - OPUS4-57567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weber, A. A1 - von Randow, M. A1 - Voigt, A.-L. A1 - von der Au, Marcus A1 - Fischer, E. A1 - Meermann, Björn A1 - Wagner, M. T1 - Ingestion and toxicity of microplastics in the freshwater gastropodLymnaea stagnalis: No microplastic-induced effects alone or incombination with copper N2 - The interaction of microplastics with freshwater biota and their interaction with other stressors is still not very well understood. Therefore, we investigated the ingestion, excretion and toxicity of microplastics in the freshwater gastropod Lymnaea stagnalis. MP ingestion was analyzed as tissues levels in L. stagnalis after 6–96 h of exposure to 5–90 μm spherical polystyrene (PS) microplastics. To understand the excretion, tissue levels were determined after 24 h of exposure followed by a 12 h–7 d depuration period. To assess the toxicity, snails were exposed for 28 d to irregular PS microplastics (<63 μm, 6.4–100,000 particles mL−1), both alone and in combination with copper as additional stressor. To compare the toxicity of natural and synthetic particles, we also included diatomite particles. Microplastics ingestion and excretion significantly depended on the particle size and the exposure/depuration duration. An exposure to irregular PS had no effect on survival, reproduction, energy reserves and oxidative stress. However, we observed slight effects on immune cell phagocytosis. Exposure to microplastics did not exacerbate the reproductive toxicity of copper. In addition, there was no pronounced difference between the effects of microplastics and diatomite. The tolerance towards microplastics may originate from an adaptation of L. stagnalis to particle-rich environments or a general stress resilience. In conclusion, despite high uptake rates, PS fragments do not appear to be a relevant stressor for stress tolerant freshwater gastropods considering current environmental levels of microplastics. KW - Lymnaea stagnalis KW - Microplastic-induced effects KW - Mixture toxicity PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-513551 DO - https://doi.org/10.1016/j.chemosphere.2020.128040 VL - 263 SP - 128040 PB - Elsevier Ltd. AN - OPUS4-51355 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weber, K. A1 - Weber, M. A1 - Menneken, M. A1 - Kral, A. G. A1 - Mertz-Kraus, R. A1 - Geisler, T. A1 - Vogl, Jochen A1 - Tütken, T. T1 - Diagenetic stability of non-traditional stable isotope systems (Ca, Sr, Mg, Zn) in teeth – An in-vitro alteration experiment of biogenic apatite in isotopically enriched tracer solution N2 - Stable isotope ratios and trace element concentrations of fossil bones and teeth are important geochemical proxies for the reconstruction of diet and past environment in archaeology and palaeontology. However, since diagenesis can significantly alter primary diet-related isotope signatures and elemental compositions, it is important to understand and quantify alteration processes. Here, we present the results of in-vitro Alteration experiments of dental tissues from a modern African elephant molar reacted in aqueous solutions at 30 °C and 90 °C for 4 to 63 days. Dental cubes with ≈ 3 mm edge length, comprising both enamel and dentin, were placed into 2 mL of acidic aqueous solution enriched in different isotopes (25Mg, 44Ca, 67Zn, 86Sr, initial pH 1). Element and isotope distribution profiles across the reacted cubes were measured with LA-(MC-)ICP-MS and EMPA, while potential effects on the bioapatite crystal structure were characterised by Raman spectroscopy. In all experiments isotope ratios measured by LA-(MC-)ICP-MS revealed an alteration of the enamel in the outer ≈ 200–300 μm. In contrast, dentin was fully altered (≈ 1.4 mm) after one week at 90 °C while the alteration did not exceed a depth of 150–200 μm during the 30 °C experiments. Then, the tracer solution started also to penetrate through the enamel-dentin junction into the innermost enamel, however, leaving the central part of the enamel unaltered, even after three months. The Raman spectra suggest an initial demineralisation in the acidic environment while organic matter (i.e. collagen) is still preserved. In the 90 °C experiment, Raman spectra of the v1 PO4) band of the dentin shift over time towards synthetic hydroxylapatite patterns and the Ca (and Sr) concentrations in the respective solutions decrease. This indicates precipitation of newly formed apatite. Isotope and element concentration profiles across the dental tissues reveal different exchange mechanisms for different isotope systems. Magnesium is leached from enamel and dentin, while Zn is incorporated into the apatite crystal structure. However, the distribution of both elements is not affected in the innermost enamel where their concentrations do not change over the whole duration of the experiments. We found no correlation of reaction depth in the cubes and experimental duration, which might be caused by natural variability of the dental material already at the beginning of the experiment. Our alteration experiments in a closed system at high temperatures ≤90 °C and low initial pH demonstrate that at least the central part of mm-thick mammalian enamel apatite seems to be resistant against alteration preserving its pristine bioapatite mineral structure as well as its in-vivo elemental and isotopic composition. The experiments assess diagenetic alteration in a novel multi-proxy approach using in-situ analyses in high spatial resolution. It is demonstrated that the isotopes of Ca, Sr, Zn and Mg in the dentin are prone for diagenetic alteration, while enamel is more resistant against alteration and could be used for dietary and physiological reconstructions in fossil teeth. KW - Bioapatite KW - Isotopes KW - Raman spectroscopy KW - Diagenesis KW - LA-(MC-)ICP-MS KW - EPMA PY - 2021 DO - https://doi.org/10.1016/j.chemgeo.2021.120196 VL - 572 SP - 120196 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-52447 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Winckelmann, Alexander A1 - Morcillo Garcia-Morato, Dalia A1 - Richter, Silke A1 - Recknagel, Sebastian A1 - Riedel, Jens A1 - Vogl, Jochen A1 - Panne, Ulrich A1 - Abad Andrade, Carlos Enrique T1 - Determination of lithium in human serum by isotope dilution atomic absorption spectrometry N2 - The therapeutic dose of lithium (Li) compounds, which are widely used for the treatment of psychiatric and hematologic disorders, is close to its toxic level; therefore, drug monitoring protocols are mandatory. Herein, we propose a fast, simple, and low-cost analytical procedure for the traceable determination of Li concentration in human serum, based on the monitoring of the Li isotope dilution through the partially resolved isotope shift in its electronic transition around 670.80 nm using a commercially available high-resolution continuum source graphite furnace atomic absorption spectrometer. With this technique, serum samples only require acidic digestion before analysis. The procedure requires three measurements—an enriched 6Li spike, a mixture of a certified standard solution and spike, and a mixture of the sample and spike with a nominal 7Li/6Li ratio of 0.82. Lanthanum has been used as an internal spectral standard for wavelength correction. The spectra are described as the linear superposition of the contributions of the respective isotopes, each consisting of a spin-orbit doublet, which can be expressed as Gaussian components with constant spectral position and width and different relative intensity, reflecting the isotope ratio in the sample. Both the spectral constants and the correlation between isotope ratio and relative band intensity have been experimentally obtained using commercially available materials enriched with Li isotopes. The Li characteristic mass (mc) obtained corresponds to 0.6 pg. The procedure has been validated using five human serum certified reference materials. The results are metrologically comparable and compatible to the certified values. The measurement uncertainties are comparable to those obtained by the more complex and expensive technique, isotope dilution mass spectrometry. KW - Lithium KW - Human serum KW - Isotope dilution KW - Atomic absorption spectrometry KW - High-resolution continuum source graphite furnace atomic absorption spectrometry PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532446 DO - https://doi.org/10.1007/s00216-021-03636-6 VL - 414 IS - 1 SP - 251 EP - 256 PB - Springer CY - Berlin AN - OPUS4-53244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Winckelmann, Alexander A1 - Nowak, S. A1 - Richter, Silke A1 - Recknagel, Sebastian A1 - Riedel, Jens A1 - Vogl, Jochen A1 - Panne, Ulrich A1 - Abad Andrade, Carlos Enrique T1 - High-Resolution Atomic Absorption Spectrometry Combined With Machine Learning Data Processing for Isotope Amount Ratio Analysis of Lithium N2 - An alternative method for lithium isotope amount ratio analysis based on a combination of high-resolution atomic absorption spectrometry and spectral data analysis by machine learning (ML) is proposed herein. It is based on the well-known isotope shift of approximately 15 pm for the electronic transition 22P←22S at around the wavelength of 670.8 nm, which can be measured by the state-of-the-art high-resolution continuum source graphite furnace atomic absorption spectrometry. For isotope amount ratio analysis, a scalable tree boosting ML algorithm (XGBoost) was employed and calibrated using a set of samples with 6Li isotope amount fractions, ranging from 0.06 to 0.99 mol mol–1, previously determined by a multicollector inductively coupled plasma mass spectrometer (MC-ICP-MS). The calibration ML model was validated with two certified reference materials (LSVEC and IRMM-016). The procedure was applied toward the isotope amount ratio determination of a set of stock chemicals (Li2CO3, LiNO3, LiCl, and LiOH) and a BAM candidate reference material NMC111 (LiNi1/3Mn1/3Co1/3O2), a Li-battery cathode material. The results of these determinations were compared with those obtained by MC-ICP-MS and found to be metrologically comparable and compatible. The residual bias was −1.8‰, and the precision obtained ranged from 1.9 to 6.2‰. This precision was sufficient to resolve naturally occurring variations, as demonstrated for samples ranging from approximately −3 to +15‰. To assess its suitability to technical applications, the NMC111 cathode candidate reference material was analyzed using high-resolution continuum source atomic absorption spectrometry with and without matrix purification. The results obtained were metrologically compatible with each other. KW - Lithium KW - Isotope KW - Machine learning KW - Algorithms KW - Reference material KW - AAS KW - Atomic Absorption Spectrometry PY - 2021 DO - https://doi.org/10.1021/acs.analchem.1c00206 SN - 1520-6882 VL - 93 IS - 29 SP - 10022 EP - 10030 PB - American Chemical Society CY - Washington, DC, USA AN - OPUS4-53028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Xiao, J. A1 - Vogl, Jochen A1 - Rosner, M. A1 - Deng, L. A1 - Jin, Z. T1 - A validated analytical procedure for boron isotope analysis in plants by MC-ICP-MS N2 - Boron (B) is an essential micronutrient for plant growth. Lack of valid methods for pretreatment and measurement of δ11B in plant restrict applications of it in the biosphere. Dry ashing, one step cation exchange and micro-sublimation were combined to separate and purify boron (B) in plant tissues. The low procedure blank, high B recovery and the accurate δ11B values of the plant reference materials demonstrate that this method is suitable and valid for B pretreatment and δ11B measurement in plant samples by MC-ICP-MS. Based on this method, the δ11B in different plants (Brassica napus, Chenopodium album L, moss, lichen, and Nostoc commune) was analyzed. For Brassica napus, δ11B increased gradually from root to leaf, and then decreased to rapeseed. For the same parts, the δ11B increased from the lower parts to the higher parts. This variation may be due to the B(OH)3 transporter of NIP6;1 and the incorporation of B into the cell. The reason for lower δ11B values in shell and rapeseed compared to those in leaves presumably is to the preferred Transport of borate in the phloem. The largest δ11B fractionation between leaf and root in Brassica napus and Chenopodium album L was +24.2‰ and +26.6‰, respectively. The large variation and fractionation of δ11B within plants indicates that δ11B is a good tracer to study the B translocation mechanisms and metabolism within plants. The δ11B in Nostoc commune, lichen, and moss showed variations of -4.1‰ to +21.5‰, −9.4‰ to +7.3‰, and −18.3‰ to +11. 9‰, respectively. In the same site, δ11B in different plants ranked Nostoc commune>moss>lichen and δ11B in mosses growing in different environment ranked soil>tree>rock. Rain and soil available B are the main B sources for these plants. The δ11B in Nostoc commune, lichen, and moss may be a useful tracer to study the atmospheric B input. In the future, plants culture experiments under certain environments and studies from molecular level are necessary to decipher the variation of δ11B and fractionation mechanisms within plants. KW - Boron isotope KW - Isotopic fractionation KW - Micro-sublimation KW - Plant tissue KW - MC-ICP-MS PY - 2019 DO - https://doi.org/10.1016/j.talanta.2018.12.087 SN - 0039-9140 SN - 1873-3573 VL - 196 SP - 389 EP - 394 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-47160 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Xiao, J. A1 - Vogl, Jochen A1 - Rosner, M. A1 - Jin, Z. T1 - Boron isotope fractionation in soil-plant systems and its influence on biogeochemical cycling N2 - Boron (B) is an essential mineral nutrient for higher plants. Although B plant nutrition is well studied, the B isotope fractionation at the soil-plant interface, within plant metabolism, and its influence on biogeochemical cycling is not fully understood. Boron concentrations and isotope variations (δ11B) of the dicotyledonous plants of Chenopodium album and Brassica napus and their growing soils along a climatic gradient were analyzed to decipher these unresolved issues of the B behavior. The boron concentrations and δ11B values show an increasing trend from roots to leaves for both plants, while a decreasing trend from flower to shell and to seed for Brassica napus. A large boron isotope fractionation occurs within the plants with median Δ11Bleaf-root ≈ +20‰, which is related to different boron transporters and transportation ways. Formation of borate dimerized rhamnogalacturonan II in cell and B(OH)3 transportation in xylem lead to heavier δ11B values from root to stem and leaf while B(OH)4􀀀 transportation in phloem lead to lighter δ11B values from flower to shell and seed. Although samples cover a distinct transect with systematically different climatic conditions, Δδ11B within the individual plant compartments and between the bulk plants and the soil available B do not show any systematic variation. This suggests that B uptake from the soil into Chenopodium album and Brassica napus occurs without a distinct isotope fractionation at the soil-plant interface (median Δ11Bbulkplant-soil = 􀀀 0.2‰) and plants are able to regulate boron uptake. Both the observed large B fractionation within plant and low or absent B isotope fractionation at the soil-plant interface may have profound implications for the biological and geological B cycle. If this observed boron behavior also exists in other plants, their litters would be an important source for exporting 11B-rich biological material from continental ecosystems via rivers to the global oceans. This may be helpful for the explanation of ocean B cycle and the increasing δ11B values over the Cenozoic. KW - Boron isotopic composition KW - Boron isotope fractionation KW - Soil available boron KW - Biological boron recycling KW - Chenopodium album KW - Brassica napus PY - 2022 DO - https://doi.org/10.1016/j.chemgeo.2022.120972 SN - 0009-2541 VL - 606 SP - 1 EP - 8 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-55031 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yang, L. A1 - Vogl, Jochen A1 - Mann, J. A1 - Kraft, R. A1 - Vocke, R. A1 - Pramann, A. A1 - Eberhardt, J. A1 - Rienitz, O. A1 - Lee, K.-S. A1 - Lim, J. S. A1 - Sobina, E. A1 - Song, P. A1 - Wang, J. A1 - Mester, Z. A1 - Meija, J. T1 - Copper isotope delta measurements in high purity materials: CCQM-P213 pilot study N2 - Accurate and precise isotope ratio measurements of heavy elements are playing an increasinglyimportant role in modern analytical sciences and have numerous applications. Today, isotope ratio measurements are typically performed with two principal techniques: thermal ionization mass spectrometry (TIMS) and multiple collector-inductively coupled plasma mass spectrometry (MC-ICP-MS). To obtain accurate results by mass spectrometry, isotopic certified reference materials (iCRMs) are needed for mass bias correction and for the validation of the method used for analysis.Thus, it is of paramount importance to achieve measurement comparability of all data reported, and to assess measurement capability of each CRM producer/National Metrology Institute (NMI). Therefore, the international comparison (CCQM-P213) was performed to assess the analytical capabilities of NMIs for the accurate determination of copper isotope ratio delta values in high purity materials. The study was proposed by the coordinating laboratories, National Research Council Canada (NRC), National Institute of Standards and Technology (NIST), Bundesanstalt für Materialforschung und -prüfung (BAM) and Physikalisch-Technische Bundesanstalt (PTB), as an activity of the Isotope Ratio Working Group (IRWG) of the Consultative Committee for Amount of Substance - Metrology in Chemistry and Biology (CCQM). Participants included six NMIs and one designated institute (DI) from the six countries. Although no measurement method was prescribed by the coordinating laboratories, MC-ICP-MS with either standard-sample bracketing (SSB) or combined SSB with internal normalization (C-SSBIN) models for mass bias correction were recommended. Results obtained from the six NMIs and one DI were in good agreement. KW - Comparability KW - Traceability KW - Metrology KW - Isotope delta KW - Copper PY - 2023 DO - https://doi.org/10.1088/0026-1394/60/1A/08019 VL - 60 IS - 1A SP - 1 EP - 23 PB - IOP Science AN - OPUS4-58040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - You, Zengchao A1 - Winckelmann, Alexander A1 - Vogl, Jochen A1 - Recknagel, Sebastian A1 - Abad Andrade, Carlos Enrique T1 - Determination of calcium, iron, and selenium in human serum by isotope dilution analysis using nitrogen microwave inductively coupled atmospheric pressure plasma mass spectrometry (MICAP-MS) N2 - In this study, we demonstrate the applicability of nitrogen microwave inductively coupled atmospheric pressure mass spectrometry (MICAP-MS) for Ca, Fe, and Se quantification in human serum using isotope dilution (ID) analysis. The matrix tolerance of MICAP-MS in Na matrix was investigated, uncovering that high Na levels can suppress the signal intensity. This suppression is likely due to the plasma loading and the space charge effect. Moreover, 40Ca and 44Ca isotopic fractionation was noted at elevated Na concentration. Nine certified serum samples were analyzed using both external calibration and ID analysis. Overestimation of Cr, Zn, As, and Se was found in the results of external calibration, which might be resulted from C-induced polyatomic interference and signal enhancement, respectively. Further investigations performed with methanol showed a similar enhancement effect for Zn, As, and Se, potentially supporting this assumption. The mass concentrations determined with ID analysis show metrological compatibility with the reference values, indicating that MICAP-MS combined with ID analysis can be a promising method for precise Ca, Fe, and Se determination. Moreover, this combination reduces the influences of matrix effects, broadening the applicability of MICAP-MS for samples with complex matrix. KW - Selenium KW - Nitrogen microwave inductively coupled atmospheric pressure mass spectrometry KW - Isotope dilution KW - Human serum KW - Calcium KW - Iron PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598664 DO - https://doi.org/10.1007/s00216-024-05274-0 SN - 1618-2642 SP - 3117 EP - 3125 PB - Springer CY - Berlin AN - OPUS4-59866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zimmermann, T. A1 - von der Au, Marcus A1 - Reese, A. A1 - Klein, O. A1 - Hildebrandt, L. A1 - Pröfrock, D. T1 - Substituting HF by HBF4 – an optimized digestion method for multi-elemental sediment analysis via ICP-MS/MS N2 - Determination of elemental mass fractions in sediments plays a major role in evaluating the environmental status of aquatic ecosystems. Herewith, the optimization of a new total digestion protocol and the subsequent analysis of 48 elements in different sediment reference materials (NIST SRM 2702, GBW 07313, GBW 07311 and JMC-2) based on ICP-MS/MS detection is presented. The developed method applies microwave acid digestion and utilizes HBF4 as fluoride source for silicate decomposition. Similar to established protocols based on HF, HBF4 ensures the dissolution of the silicate matrix, as well as other refractory oxides. As HBF4 is not acutely toxic; no special precautions have to be made and digests can be directly measured via ICP-MS without specific sample inlet systems, evaporation steps or the addition of e.g. H3BO3, in order to mask excess HF. Different acid mixtures with and without HBF4 were evaluated in terms of digestion efficiency based on the trace metal recovery. The optimized protocol (5 mL HNO3, 2 mL HCL, 1 mL HBF4) allows a complete dissolution of the analyzed reference materials, as well as quantitative recoveries for a wide variety of certified analytes. Low recoveries for e.g. Sr, Ba and rare earth elements due to fluoride precipitation of HF-based digestions protocols, can be avoided by the usage of HBF4 instead. Based on the usage of high purity HBF4 all relevant trace, as well as matrix elements can be analyzed with sufficiently low LOQs (0.002 μg L−1 for U up to 6.7 μg L−1 for Al). In total, 34 elements were within a recovery range of 80%–120% for all three analyzed reference materials GBW 07313, GBW 07311 and JMC-2. 14 elements were outside a recovery range of 80%–120% for at least one of the analyzed reference materials. KW - Reference Materials KW - Sediment KW - HF free Digestion PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510480 DO - https://doi.org/10.1039/D0AY01049A SP - 1 EP - 10 PB - Royal Society of Chemistry AN - OPUS4-51048 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zweigle, J. A1 - Capitain, C. A1 - Simon, Fabian Michael A1 - Roesch, Philipp A1 - Bugsel, B. A1 - Zwiener, C. T1 - Non-extractable PFAS in functional textiles − Characterization by complementary methods: oxidation, hydrolysis, and fluorine sum parameters N2 - Per- and polyfluoroalkyl substances (PFAS) are widely used for durable water-repellent finishing of different fabrics and textiles like outdoor clothing, carpets, medical textiles and more. Existing PFAS extraction techniques followed by target analysis are often insufficient in detecting widely used side-chain fluorinated polymers (SFPs) that are barely or non-extractable. SFPs are typically copolymers consisting of a non-fluorinated backbone with perfluoroalkyl side-chains to obtain desired properties. We compared the accessible analytical information and performance of complementary techniques based on oxidation (dTOP assay, PhotoTOP), hydrolysis (THP assay), standard extraction, extractable organic fluorine (EOF), and total fluorine (TF) with five functional textiles and characterized 7 further textiles only by PhotoTOP oxidation. The results show that when applied directly to textile samples, oxidation by dTOP and PhotoTOP and also hydrolysis by the THP are able to capture large fractions of the TF in form of perfluoroalkyl side-chains present in the textiles while methods relying on extracts (EOF, target and non-target analysis) were much lower (e.g., factor ~25-50 lower). The conversion of large fractions of the measured TF into PFCAs or FTOHs from fluorinated side chains is in contrast to previous studies. Concentrations ranged from