TY - JOUR A1 - Segovia, J. J. A1 - Tuma, Dirk A1 - Lozano-Martín, D. A1 - Moreau, A. A1 - Martín, M. C. A1 - Vega-Maza, D. T1 - Speed of sound data and acoustic virial coefficients of two binary (N2 + H2) mixtures at temperatures between (260 and 350) K and at pressures between (0.5 and 20) MPa N2 - This work aims to address the technical concerns related to the thermodynamic characterization of gas mixtures blended with hydrogen for the implementation of hydrogen as a new energy vector. For this purpose, new experimental speed of sound measurements have been done in gaseous and supercritical phases of two binary mixtures of nitrogen and hydrogen using the most accurate technique available, i.e., the spherical acoustic resonator, yielding an experimental expanded (k = 2) uncertainty of only 220 parts in 106 (0.022%). The measurements cover the pressure range between (0.5 and 20) MPa, the temperature range between (260 and 350) K, and the composition range with a nominal mole percentage of hydrogen of (5 and 10) mol%, respectively. From the speed of sound data sets, thermophysical properties that are relevant for the characterization of the mixture, namely the second βa and third γa acoustic virial coefficients, are derived. These results are thoroughly compared and discussed with the established reference mixture models valid for mixtures of nitrogen and hydrogen, such as the AGA8-DC92 EoS, the GERG-2008 EoS, and the recently developed adaptation of the GERG-2008 EoS, here denoted GERG-H2_improved EoS. Special attention has been given to the effect of hydrogen concentration on those properties, showing that only the GERG-H2_improved EoS is consistent with the data sets within the experimental uncertainty in most measuring conditions. KW - Speed of sound KW - Acoustic resonance KW - Binary gas mixture PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551482 DO - https://doi.org/10.1016/j.jct.2022.106791 SN - 0021-9614 VL - 171 SP - 1 EP - 13 PB - Elsevier B. V. CY - Amsterdam AN - OPUS4-55148 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sichler, Theresa Constanze A1 - Adam, Christian A1 - Barjenbruch, M. A1 - Montag, D. A1 - Mauch, Tatjana A1 - Sommerfeld, Thomas A1 - Ehm, J.H. T1 - Variation of the element composition of municipal sewage sludges in the context of new regulations on phosphorus recovery in Germany N2 - Phosphorus (P) recovery is obligatory for all sewage sludges with more than 20 g P/kg dry matter (DM) from 2029 in Germany. Nine wastewater treatment plants (WWTPs) were chosen to investigate variations of phosphorus contents and other parameters in sewage sludge over the year. Monthly sewage sludge samples from each WWTP were analyzed for phosphorus and other matrix elements (C, N, H, Ca, Fe, Al, etc.), for several trace elements (As, Cr, Mo, Ni, Pb, Sn) and loss of ignition. Among the nine WWTPs, there are four which have phosphorus contents both above and below the recovery limit of 20 g/kg DM along the year. Considering the average phosphorus content over the year, only one of them is below the limit. Compared to other matrix elements and parameters, phosphorus fuctuations are low with an average of 7% over all nine WWTPs. In total, only hydrogen and carbon are more constant in the sludge. In several WWTPs with chemical phosphorus elimination, phosphorus fuctuations showed similar courses like iron and/or aluminum. WWTPs with chamber flter presses rather showed dilution efects of calcium dosage. As result of this study, monthly phosphorus measurement is highly recommended to determine whether a WWTP is below the 20 g/kg DM limit. KW - Sewage sludge KW - Phosphorus recovery KW - Wastewater KW - Phosphorus elimination PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-557499 DO - https://doi.org/10.1186/s12302-022-00658-4 SN - 2190-4707 VL - 34 IS - 1 SP - 1 EP - 12 PB - Springer Nature CY - Berlin AN - OPUS4-55749 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sieber, M. J. A1 - Wilke, M. A1 - Appelt, O. A1 - Oelze, Marcus A1 - Koch-Müller, M. T1 - Melting relations of Ca–Mg carbonates and trace element signature of carbonate melts up to 9 GPa – A proxy for melting of carbonated mantle lithologies N2 - The most profound consequences of the presence of Ca–Mg carbonates (CaCO3–MgCO3) in the Earth’s upper mantle may be to lower the melting temperatures of the mantle and control the melt composition. Low-degree partial melting of a carbonate-bearing mantle produces CO2-rich, silica-poor melts compositionally imposed by the melting relations of carbonates. Thus, understanding the melting relations in the CaCO3–MgCO3 system facilitates the interpretation of natural carbonate-bearing silicate systems. We report the melting relations of the CaCO3–MgCO3 system and the partition coefficient of trace elements between carbonates and carbonate melt from experiments at high pressure (6 and 9 GPa) and temperature (1300–1800 ◦C) using a rocking multi-anvil press. In the absence of water, Ca–Mg carbonates are stable along geothermal gradients typical of subducting slabs. Ca–Mg carbonates (∼ Mg0.1–0.9Ca0.9–0.1CO3) partially melt beneath mid-ocean ridges and in plume settings. Ca–Mg carbonates melt incongruently, forming periclase crystals and carbonate melt between 4 and 9 GPa. Furthermore, we show that the rare earth element (REE) signature of Group-I kimberlites, namely strong REE fractionation and depletion of heavy REE relative to the primitive mantle, is resembled by carbonate melt in equilibrium with Ca-bearing magnesite and periclase at 6 and 9 GPa. This suggests that the dolomite–magnesite join of the CaCO3–MgCO3 system might be useful to approximate the REE signature of carbonate-rich melts parental to kimberlites. KW - High pressure experiments KW - Laser Ablation PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561197 DO - https://doi.org/10.5194/ejm-34-411-2022 SN - 0935-1221 VL - 34 IS - 5 SP - 411 EP - 424 PB - Copernicus Publications CY - Göttingen AN - OPUS4-56119 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Fabian A1 - von der Au, Marcus A1 - Gehrenkemper, Lennart A1 - Meermann, Björn T1 - An optimized method for PFAS analysis using HR–CS–GFMAS via GaF detection N2 - The analysis of per- and polyfluoroalkyl substances (PFAS) via sum parameters like extractable organic fluorine (EOF) in combination with high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR–CS–GFMAS) is highly promising regarding fluorine sensitivity and selectivity. However, the HR–CS–GFMAS method includes several drying and heating steps which can lead to losses of volatile PFAS before the molecular formation step using e.g., GaF formation. Hence, the method leads to a strong discrimination of PFAS within the EOF depending on their physical/chemical properties and is therefore associated with reduced accuracy. To reduce this discrepancy and to indicate realistic PFAS pollution values, an optimization of the HR–CS–GFMAS method for PFAS analysis is needed. Hence, we determined fluorine response factors of several PFAS with different physical/chemical properties upon application of systematic optimization steps. We could therefore improve the method's sensitivity for PFAS analysis using a modifier drying pre-treatment step followed by a sequential injection of sample solutions. The highest improvement in sensitivity of volatile PFAS was shown upon addition of a Mg modifier during drying pre-treatment. Thereby, during optimization the relative standard deviation of fluorine response factors could be reduced from 55 % (initial method) to 27 % (optimized method) leading to a more accurate determination of organofluorine sum parameters. The method provides an instrumental LOD and LOQ of β(F) 1.71 μg/L and 5.13 μg/L, respectively. Further validation aimed to investigate several matrix effects with respect to water matrices. Here, substance-specific behavior was observed. For example, perfluorooctanoic acid (PFOA) which was used as calibrator, showed signal suppressions upon high chloride concentrations (>50 mg/L). Hence, a thorough separation of Cl from analytes during sample preparation is needed for accurate sum parameter analysis. KW - PFAS KW - GF-AAS KW - Method optimization PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610522 DO - https://doi.org/10.1016/j.talanta.2024.126811 VL - 281 SP - 1 EP - 11 PB - Elsevier B.V. AN - OPUS4-61052 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Smeir, E. A1 - Leberer, S. A1 - Blumrich, A. A1 - Vogler, G. A1 - Vasiliades, A. A1 - Dresen, S. A1 - Jaeger, Carsten A1 - Gloaguen, Y. A1 - Klose, C. A1 - Beule, D. A1 - Schulze, P. A1 - Bodmer, R. A1 - Foryst-Ludwig, A. A1 - Kintscher, U. T1 - Depletion of Cardiac Cardiolipin Synthase Alters Systolic and Diastolic Function N2 - Cardiolipin (CL) is a major cardiac mitochondrial phospholipid maintaining regular mitochondrial morphology and function in cardiomyocytes. Cardiac CL production includes ist biosynthesis and a CL-remodeling process. Here we studied the impact of CL-biosynthesis and the enzyme Cardiolipin Synthase (CLS) on cardiac function. CLS and cardiac CL-species were significantly downregulated in cardiomyocytes following catecholamine-induced cardiac damage in mice, accompanied by increased oxygen consumption rates, signs of oxidative stress and mitochondrial uncoupling. RNAi-mediated cardiomyocyte-specific knockdown of CLS in Drosophila melanogaster resulted in marked cardiac dilatation, severe impairment of systolic performance and slower diastolic filling velocity assessed by fluorescence-based heart imaging. Finally, we showed that CL72:8 is significantly decreased in cardiac samples from patients with heart failure with reduced ejection fraction (HFrEF). In summary, we identified CLS as a regulator of cardiac function. Considering the cardiac depletion of CL-species in HFrEF, pharmacological targeting of CLS may be a promising therapeutic approach.zeige mehrzeige weniger KW - High-resolution mass spectrometry KW - Nontarget analysis KW - Heart failure KW - Cardiolipins KW - Lipidomics PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-536833 DO - https://doi.org/10.1016/j.isci.2021.103314 VL - 24 IS - 11 SP - 103314 PB - Cell Press AN - OPUS4-53683 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Soares, J. X. A1 - Wegner, Karl David A1 - Ribeiro, D. S. M. A1 - Melo, A. A1 - Häusler, I. A1 - Santos, J. L. M. A1 - Resch-Genger, Ute T1 - Rationally designed synthesis of bright AgInS2/ZnS quantum dots with emission control N2 - In the blossoming field of Cd-free semiconductor quantum dots (QDs), ternary I–III–VI QDs have received increasing attention due to the ease of the environmentally friendly synthesis of high-quality materials in water, their high photoluminescence (PL) Quantum yields (QYs) in the red and near infrared (NIR) region, and their inherently low toxicity. Moreover, their oxygen-insensitive long PL lifetimes of up to several hundreds of nanoseconds close a gap for applications exploiting the compound-specific parameter PL lifetime. To overcome the lack of reproducible synthetic methodologies and to enable a design-based control of their PL properties, we assessed and modelled the synthesis of high-quality MPA-capped AgInS2/ZnS (AIS/ZnS) QDs. Systematically refined Parameters included reaction time, temperature, Ag:In ratio, S:In ratio, Zn:In ratio, MPA:In ratio, and pH using a design-of-experiment approach. Guidance for the optimization was provided by mathematical models developed for the application-relevant PL parameters, maximum PL wavelength, QY, and PL lifetime as well as the elemental composition in terms of Ag:In:Zn ratio. With these experimental data-based models, MPA:In and Ag:In ratios and pH values were identified as the most important synthesis parameters for PL Control and an insight into the connection of these parameters could be gained. Subsequently, the experimental conditions to synthetize QDs with tunable emission and high QY were predicted. The excellent agreement between the predicted and experimentally found PL features confirmed the reliability of our methodology for the rational design of high quality AIS/ZnS QDs with defined PL features. This approach can be straightforwardly extended to other ternary and quaternary QDs and to doped QDs. KW - Modelling KW - Nanoparticle KW - AIS KW - Semiconductor quantum dot KW - Design of experiment KW - Photoluminescence KW - Quantum yield KW - Surface chemistry KW - Synthesis KW - Lifetime PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510075 DO - https://doi.org/10.1007/s12274-020-2876-8 VL - 13 IS - 9 SP - 2438 EP - 2450 PB - Springer AN - OPUS4-51007 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Solovyev, N. A1 - El-Khatib, Ahmed A1 - Costas-Rodrigues, M. A1 - Schwab, K. A1 - Griffin, E. A1 - Raab, A. A1 - Platt, B. A1 - Theuring, F. A1 - Vogl, Jochen A1 - Vanhaecke, F. T1 - Cu, Fe and Zn isotope ratios in murine Alzheimer's disease models suggest specific signatures of amyloidogenesis and tauopathy N2 - Alzheimer’s disease (AD) is characterized by accumulation of tau and amyloid-beta in the brain, and recent evidence suggests a correlation between associated protein aggregates and trace elements, such as copper, iron and zinc. In AD, distorted brain redox homeostasis and complexation by amyloid-beta and hyperphosphorylated tau May alter the isotopic composition of essential mineral elements. Therefore, high-precision isotopic analysis may reveal changes in the homeostasis of these elements. We used inductively coupled plasma-mass spectrometry (ICP-MS)-based techniques to determine the total Cu, Fe and Zn contents in the brain, as well as their isotopic compositions in both mouse brain and serum. Results for male transgenic tau (Line 66, L66) and amyloid/presenilin (5xFAD) mice were compared to those for the corresponding age- and gendermatched wild-type control mice (WT). Our data show that L66 brains showed significantly higher Fe levels than the corresponding WT. Significantly less Cu, but more Zn was found in 5xFAD brains. We observed significantly lighter isotopic compositions of Fe (enrichment in the lighter isotopes) in the brain, and in serum of L66 mice compared to WT. For 5xFAD mice, Zn exhibited a trend towards a lighter isotopic composition in brain and a heavier isotopic composition in serum compared to WT. Neither mouse model yielded differences in the isotopic composition of Cu. Our findings indicate significant pathology-specific alterations of Fe and Zn brain homeostasis in mouse models of AD. The associated changes in isotopic composition May serve as a marker for proteinopathies Underlying AD and other types of dementia. KW - Alzheimer’s disease KW - Tau KW - Amyloid-beta KW - Copper KW - Iron KW - Zinc KW - Multi-collector inductively coupled plasma-mass spectrometry (ICP-MS) KW - Brain KW - Serum KW - Isotopic analysis KW - Total element determination PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520214 DO - https://doi.org/10.1016/j.jbc.2021.100292 VL - 296 SP - 100292 PB - Elsevier Inc. CY - Amsterdam AN - OPUS4-52021 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 - Sommerfeld, Thomas A1 - Riedel, Juliane A1 - Lisec, Jan A1 - Mauch, Tatjana A1 - Richter, Silke A1 - Koch, Matthias T1 - Development of a certified reference material for per- and polyfluoroalkyl substances (PFAS) in textiles N2 - Per- and polyfluoroalkyl substances (PFASs) are a large group of emerging organic pollutants that contaminate the environment, food, and consumer products. Textiles and other outdoor products are a major source of PFAS exposure due to their water-repellent impregnations. Determination of PFASs in textiles is increasingly important for enhancing their contribution to the circular economy. While maximum levels and restrictions exist for certain key compounds under the Stockholm Convention on Persistent Organic Pollutants and the REACH regulation, certified reference materials (CRMs) are not currently available. To address this issue, the first CRM for determining PFASs in outdoor textiles (BAM-B003) was developed. It fully complies with the requirements of ISO 17034 and ISO 33405. This work presents the entire process of CRM development process, including preparation, a homogeneity study, a stability study, and value assignment. Certification was based on an in-house study at BAM using liquid chromatography tandem mass spectrometry (LC–MS/MS) with stable isotope dilution analysis (SIDA). The certified mass fractions of 18 PFASs range widely from 0.46 to 69 µg/kg, with a prevalence of PFOA (69 µg/kg), PFOS (41 µg/kg) and PFHxA (35 µg/kg) exceeding legal limits. BAM-B003 is intended for analytical quality control and contributes to improving the chemical safety of textiles and strengthening the circular economy. KW - Reference Material KW - PFAS KW - Textiles PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641040 DO - https://doi.org/10.1007/s00216-025-06098-2 SN - 1618-2642 SP - 1 EP - 9 PB - Springer Science and Business Media LLC AN - OPUS4-64104 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sowoidnich, K. A1 - Maiwald, M. A1 - Ostermann, Markus A1 - Sumpf, B. T1 - Shifted excitation Raman difference spectroscopy for soil component identification and soil carbonate determination in the presence of strong fluorescence interference N2 - Detailed knowledge about soil composition is an important prerequisite for many applications, for example precision agriculture. Current standard laboratory methods are complex and time-consuming but could be complemented by non-invasive optical techniques. Its capability to provide a molecular fingerprint of individual soil components makes Raman spectroscopy a very promising candidate. A major challenge is strong fluorescence interference inherent to soil, but this issue can be overcome effectively using shifted excitation Raman difference spectroscopy (SERDS). A customized dual-wavelength diode laser emitting at 785.2 and 784.6 nm was used to investigate 117 soil samples collected from an agricultural field along a distance of 624 m and down to depths of 1 m. To address soil spatial heterogeneity, a raster scan approach comprising 100 measurement spots per sample was applied. Based on the Raman spectroscopic fingerprint extracted from intense fluorescence interference by SERDS, 13 mineral soil constituents were identified, and even closely related molecular species could be discriminated, for example polymorphs of titanium dioxide and calcium carbonate. For the first time, the capability of SERDS is demonstrated to predict the calcium carbonate content as an important soil parameter using partial least squares regression (R2 = 0.94, root mean square error of cross-validation RMSECV = 2.1%). Our findings demonstrate that SERDS can extract a wealth of spectroscopic information from disturbing backgrounds enabling qualitative and quantitative soil analysis. This highlights the large potential of SERDS for precision agriculture but also in further application areas, for example geology, cultural heritage and planetary exploration. KW - Calcium carbonate KW - Raman spectroscopy KW - Soil KW - X-Ray fluorescence KW - SERDS PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569016 DO - https://doi.org/10.1002/jrs.6500 SN - 0377-0486 IS - Special Issue SP - 1 EP - 14 PB - John Wiley & Sons Ltd. CY - Hoboken, New Jersey, USA AN - OPUS4-56901 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sowoidnich, Kay A1 - Pätzold, Stefan A1 - Ostermann, Markus A1 - Sumpf, Bernd A1 - Maiwald, Martin T1 - Qualitative and quantitative soil characterization on an agricultural field using a portable shifted excitation Raman difference spectroscopy instrument N2 - Site-specific farmland management requires comprehensive information about the soil status to derive informed treatment decisions, e.g. for liming or fertilizer recommendations. Standard laboratory methods relying on sample collection have only limited ability to adequately capture the spatial variability of typical agricultural fields. Here, on-site analytical techniques with the potential to measure the soil properties on a substance-specific level and at the required spatial resolution could be very beneficial. Raman spectroscopy is a very promising technique for this purpose as it provides a molecular fingerprint of soil constituents. However, intrinsic soil fluorescence and daylight interference can be major issues masking characteristic Raman signals. Here, we apply an in-house developed portable shifted excitation Raman difference spectroscopy (SERDS) instrument based on a dual-wavelength diode laser emitting around 785 nm to effectively separate the Raman signals of soil from such interferences. SERDS investigations on a selected agricultural field in Germany demonstrate that the Raman spectroscopic signature of 9 soil minerals and organic carbon could successfully be separated from intense backgrounds. Using partial least squares regression against reference analyses, a successful prediction of the soil carbonate (R2 = 0.86, root mean squared error of cross validation RMSECV = 2.49%) and soil organic carbon content (R2 = 0.89, RMSECV = 0.32%) as important soil parameters is realized. The results obtained on-site with the portable instrument were confirmed by SERDS laboratory experiments of collected soil samples thus highlighting the capability and reliability of portable SERDS as promising and complementary tool for precision agriculture KW - XRF KW - Raman spectroscopy KW - Soil KW - SERDS KW - Precision agriculture PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634597 DO - https://doi.org/10.1039/d5an00178a SN - 0003-2654 VL - 150 IS - 13 SP - 2934 EP - 2944 PB - Royal Society of Chemistry (RSC) AN - OPUS4-63459 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Soyka, J. P. A1 - Witte, J. F. A1 - Wiesner, A. A1 - Krappe, A. R. A1 - Wehner, D. A1 - Alnicola, N. A1 - Paulus, B. A1 - Resch-Genger, Ute A1 - Eigler, S. T1 - [3]Radialene Fluorophores with pH-Switchable Emission and Stable Absorption Maxima N2 - The first push–pull quino [3]radialene fluorescent dye is reported. Herein, the novel bis(dicyanomethylene)-[3]radialene electron acceptor is connected to a benzimidazole donor. With protonation, a substantial redshift of fluorescence wavelength is observed, while the absorption maximum remains stable. This process is accompanied with an increased fluorescence quantum yield to about 70%. Further, the findings are explained by a combined experimental and theoretical approach, and it is found that vibronic coupling plays a crucial role. This study highlights the yet unexplored potential of [3]radialene-based motifs for the design of environment-responsive fluorophores. KW - DADQ KW - Nanographene KW - fluorescence KW - Nano KW - Particle KW - Synthesis KW - Characterization KW - Advanced material KW - Quantum yield KW - Photophysic KW - pH KW - Probe KW - Sensor KW - Lifetime KW - Polarity PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-642147 DO - https://doi.org/10.1002/ejoc.202500669 SN - 1099-0690 SP - 1 EP - 6 PB - Wiley-VCH CY - Weinheim AN - OPUS4-64214 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Spallanzani, Roberta A1 - Koga, K. A1 - Cichy, S. A1 - Wiedenbeck, M. A1 - Schmidt, B. A1 - Oelze, Marcus A1 - Wilke, M. T1 - Lithium and boron difusivity and isotopic fractionation in hydrated rhyolitic melts N2 - Lithium and boron are trace components of magmas, released during exsolution of a gas phase during volcanic activity. In this study, we determine the difusivity and isotopic fractionation of Li and B in hydrous silicate melts. Two glasses were synthesized with the same rhyolitic composition (4.2 wt% water), having diferent Li and B contents; these were studied in difusion-couple experiments that were performed using an internally heated pressure vessel, operated at 300 MPa in the temperature range 700–1250 °C for durations from 0 s to 24 h. From this we determined activation energies for Li and B difusion of 57±4 kJ/mol and 152±15 kJ/mol with pre-exponential factors of 1.53 × 10–7 m2/s and 3.80× 10–8 m2 /s, respectively. Lithium isotopic fractionation during difusion gave β values between 0.15 and 0.20, whereas B showed no clear isotopic fractionation. Our Li difusivities and isotopic fractionation results difer somewhat from earlier published values, but overall confrm that Li difusivity increases with water content. Our results on B difusion show that similarly to Li, B mobility increases in the presence of water. By applying the Eyring relation, we confrm that B difusivity is limited by viscous fow in silicate melts. Our results on Li and B difusion present a new tool for understanding degassing-related processes, ofering a potential geospeedometer to measure volcanic ascent rates. KW - Hydrated silicate melts KW - Stable isotopes KW - Diffusion KW - Isotopic fractionation PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-554496 DO - https://doi.org/10.1007/s00410-022-01937-2 VL - 177 IS - 8 SP - 1 EP - 17 PB - Springer AN - OPUS4-55449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Srivastava, Priyanka A1 - Fürstenwerth, Paul Christian A1 - Witte, J. F. A1 - Resch-Genger, Ute T1 - Synthesis and spectroscopic characterization of a fluorescent phenanthrene-rhodamine dyad for ratiometric measurements of acid pH values N2 - We present the rational design, synthesis and spectroscopic characterization of a novel dual excitation, three color emitting, pH-responsive fluorescent probe consisting of two phenanthrene and one rhodamine B units linked by click chemistry. The rhodamine moiety, excitable at λEx = 315 nm and at λEx = 560 nm in its ring-opened form, provides the pH-responsive fluorophore, while the pH-insensitive phenanthrene, excited at λEx = 315 nm, serves as inert internal reference, The presence of two phenanthrene moieties enables a blue monomer and a blueish green excimer emission at 351 nm and 500 nm, respectively. Opening of the rhodamine B spirolactam ring at an acidic pH below 5.0 (pKa = 2.59 ± 0.04) switches on its emission at 580 nm. Simultaneously, the phenanthrene excimer emission decreases caused by a change in orientation of the phenanthrene units, while the monomer emission is barely affected. This sensor design enables ratiometric measurements in the low acidic pH range utilizing the intensity ratios of the rhodamine B and phenanthrene excimer emission at 580 nm and 500 nm. Alternatively, also the intensity ratios of the rhodamine B and the phenanthrene monomer emission could be exploited or the sum of the phenanthrene monomer and excimer fluorescence. To the best of our knowledge, this is the first report of ratiometric sensing utilizing such a versatile type of tricolor emissive dyad probe bearing phenanthrene moieties and showing phenanthrene monomer and excimer emission. KW - Fluorescence KW - Optical probe KW - Sensor KW - Dye KW - Rhodamine KW - Synthesis KW - Photophysics KW - PH KW - Quantum yield KW - Quality assurance KW - Mechanism KW - Chemodosimeter KW - Phenanthrene KW - Ratiometric KW - Dyad PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530554 DO - https://doi.org/10.1039/d1nj01573g SN - 1144-0546 VL - 45 IS - 31 SP - 13755 EP - 13762 PB - Royal Society of Chemistry AN - OPUS4-53055 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Srivastava, Priyanka A1 - Tavernaro, Isabella A1 - Scholtz, Lena A1 - Genger, C. A1 - Welker, P. A1 - Schreiber, Frank A1 - Meyer, Klas A1 - Resch-Genger, Ute T1 - Dual color pH probes made from silica and polystyrene nanoparticles and their performance in cell studies N2 - Ratiometric green–red fluorescent nanosensors for fluorometrically monitoring pH in the acidic range were designed from 80 nm-sized polystyrene (PS) and silica (SiO2) nanoparticles (NPs), red emissive reference dyes, and a green emissive naphthalimide pH probe, analytically and spectroscopically characterized, and compared regarding their sensing performance in aqueous dispersion and in cellular uptake studies. Preparation of these optical probes, which are excitable by 405 nm laser or LED light sources, involved the encapsulation of the pH-inert red-fuorescent dye Nile Red (NR) in the core of self-made carboxylated PSNPs by a simple swelling procedure and the fabrication of rhodamine B (RhB)-stained SiO2-NPs from a silane derivative of pH-insensitive RhB. Subsequently, the custom-made naphthalimide pH probe, that utilizes a protonation-controlled photoinduced electron transfer process, was covalently attached to the carboxylic acid groups at the surface of both types of NPs. Fluorescence microscopy studies with the molecular and nanoscale optical probes and A549 lung cancer cells confirmed the cellular uptake of all probes and their penetration into acidic cell compartments, i.e., the lysosomes, indicated by the switching ON of the green naphthalimide fluorescence. This underlines their suitability for intracellular pH sensing, with the SiO2-based nanosensor revealing the best performance regarding uptake speed and stability. KW - Sensors KW - Silica and polystyrene nanoparticles KW - pH probe KW - Fluorescence spectroscopy KW - Cell studies KW - Dye KW - Particle synthesis PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569198 DO - https://doi.org/10.1038/s41598-023-28203-0 SN - 2045-2322 VL - 13 IS - 1 SP - 1321 EP - 1336 PB - Nature CY - London AN - OPUS4-56919 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Starkholm, A. A1 - Al-Sabbagh, Dominik A1 - Sarisozen, S A1 - von Reppert, A A1 - Rössle, M A1 - Ostermann, Markus A1 - Unger, E A1 - Emmerling, Franziska A1 - Kloo, L A1 - Svensson, P A1 - Lang, F A1 - Maslyanchuk, O. T1 - Green Fabrication of Sulfonium-Containing Bismuth Materials for High-Sensitivity X-Ray Detection N2 - Organic–inorganic hybrid materials based on lead and bismuth have recently been proposed as novel X- and gamma-ray detectors for medical imaging, non-destructive testing, and security, due to their high atomic numbers and facile preparation compared to traditional materials like amorphous selenium and Cd(Zn)Te. However, challenges related to device operation, excessively high dark currents, and long-term stability have delayed commercialization. Here, two novel semiconductors incorporating stable sulfonium cations are presented, [(CH3CH2)3S]6Bi8I30 and [(CH3CH2)3S]AgBiI5, synthesized via solvent-free ball milling and fabricated into dense polycrystalline pellets using cold isostatic compression, two techniques that can easily be upscaled, for X-ray detection application. The fabricated detectors exhibit exceptional sensitivities (14 100–15 190 µC Gyair−1 cm−2) and low detection limits (90 nGyair s−1 for [(CH3CH2)3S]6Bi8I30 and 78 nGyair s−1 for [(CH3CH2)3S]AgBiI5), far surpassing current commercial detectors. Notably, they maintain performance after 9 months of ambient storage. The findings highlight [(CH3CH2)3S]6Bi8I30 and [(CH3CH2)3S]AgBiI5 as scalable, cost-effective and highly stable alternatives to traditional semiconductor materials, offering great potential as X-ray detectors in medical and security applications. KW - Mechanochemistry KW - X-ray detectors PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630306 DO - https://doi.org/10.1002/adma.202418626 SP - 1 EP - 10 PB - Wiley VHC-Verlag AN - OPUS4-63030 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steglich, P. A1 - Bondarenko, S. A1 - Mai, C. A1 - Paul, Martin A1 - Weller, Michael G. A1 - Mai, A. T1 - CMOS-Compatible Silicon Photonic Sensor for Refractive Index Sensing Using Local Back-Side Release N2 - Silicon photonic sensors are promising candidates for lab-on-a-chip solutions with versatile applications and scalable production prospects using complementary metal-oxide semiconductor (CMOS) fabrication methods. However, the widespread use has been hindered because the sensing area adjoins optical and electrical components making packaging and sensor handling challenging. In this work, a local back-side release of the photonic sensor is employed, enabling a separation of the sensing area from the rest of the chip. This approach allows preserving the compatibility of photonic integrated circuits in the front-end of line and metal interconnects in the back-end of line. The sensor is based on a micro-ring resonator and is fabricated on wafer-level using a CMOS technology. We revealed a ring resonator sensitivity for homogeneous sensing of 106 nm/RIU. KW - Photonic biosensor KW - Lab-on-a-chip KW - Ring resonator KW - Resonance wavelength shift KW - PIC technology KW - Back-side integration PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517139 DO - https://doi.org/10.1109/LPT.2020.3019114 VL - 32 IS - 19 SP - 1241 EP - 1244 PB - IEEE AN - OPUS4-51713 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Steglich, P. A1 - Rabus, D. G. A1 - Sada, C. A1 - Paul, Martin A1 - Weller, Michael G. A1 - Mai, C. A1 - Mai, A. T1 - Silicon Photonic Micro-Ring Resonators for Chemical and Biological Sensing: A Tutorial N2 - Silicon photonic micro-ring resonators (MRR) developed on the silicon-on-insulator (SOI) platform, owing to their high sensitivity and small footprint, show great potential for many chemical and biological sensing applications such as label-free detection in environmental monitoring, biomedical engineering, and food analysis. In this tutorial, we provide the theoretical background and give design guidelines for SOI-based MRR as well as examples of surface functionalization procedures for label-free detection of molecules. After introducing the advantages and perspectives of MRR, fundamentals of MRR are described in detail, followed by an introduction to the fabrication methods, which are based on a complementary metal-oxide semiconductor (CMOS) technology. Optimization of MRR for chemical and biological sensing is provided, with special emphasis on the optimization of waveguide geometry. At this point, the difference between chemical bulk sensing and label-free surface sensing is explained, and definitions like waveguide sensitivity, ring sensitivity, overall sensitivity as well as the limit of detection (LoD) of MRR are introduced. Further, we show and explain chemical bulk sensing of sodium chloride (NaCl) in water and provide a recipe for label-free surface sensing. KW - Lab on a chip KW - Biosensor KW - Cmos KW - Silanization KW - Surface derivatization KW - Evanescent wave PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529360 DO - https://doi.org/10.36227/techrxiv.14909901.v1 SP - 1 EP - 18 PB - IEEE CY - Piscataway Township AN - OPUS4-52936 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stein, L. A1 - Wang, Cui A1 - Förster, C. A1 - Resch-Genger, Ute A1 - Heinze, K. T1 - Bulky ligands protect molecular ruby from oxygen quenching N2 - Chromium(III) complexes can show phosphorescence from the spin-flip excited doublet states 2E/2T1 in the near-infrared with high photoluminescence quantum yields and extremely long lifetimes in the absence of dioxygen. The prototype molecular ruby, [Cr(ddpd)2]3+ (ddpd = N,N’-dimethyl-N,N’-dipyridine-2-ylpyridine-2,6-diamine), has a photoluminescence quantum yield and a luminescence lifetime of 13.7% and 1.1 ms in deaerated acetonitrile, respectively. However, its luminescence is strongly quenched by 3O2 via an efficient Dexter-type energy transfer process. To enable luminescence applications of molecular rubies in solution under aerobic conditions, we explored the potential of sterically demanding ddpd ligands to shield the chromium(III) center from O2 using steady state and time-resolved photoluminescence spectroscopy. The structures of the novel complexes with sterically demanding ligands were investigated by single crystal X-ray diffraction and quantum chemically by density functional theory calculations. The O2 sensitivity of the photoluminescence was derived from absolutely measured photoluminescence quantum yields and excited state lifetimes under inert and aerobic conditions and by Stern–Volmer analyses of these data. Optimal sterically shielded chromium(III) complexes revealed photoluminescence quantum yields of up to 5.1% and excited state lifetimes of 518 μs in air-saturated acetonitrile, underlining the large potential of this ligand design approach to broaden the applicability of highly emissive chromium(III) complexes. KW - Fluorescence KW - Synthesis KW - Production KW - Optical spectroscopy KW - Ligand KW - Photophysics KW - Cr(III) KW - Mechanism KW - NIR KW - Sensor KW - Oxygen PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570807 DO - https://doi.org/10.1039/d2dt02950b VL - 51 IS - 46 SP - 17664 EP - 17670 PB - The Royal Society of Chemistry CY - Berlin AN - OPUS4-57080 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steinbeck, Christoph A1 - Jung, Nicole A1 - Bach, Felix A1 - Neumann, Steffen A1 - Herres-Pawlis, Sonja A1 - Liermann, Johannes A1 - Koepler, Oliver A1 - Bannwarth, Christoph A1 - Bender, Theo A1 - Bocklitz, Thomas A1 - Boehm, Franziska A1 - Bonatto Minella, Christian A1 - Biedermann, Frank A1 - Brack, Werner A1 - Cunha, Ricardo A1 - Czodrowski, Paul A1 - Eberl, Franziska A1 - Engel, Thomas A1 - Engstfeld, Albert A1 - Fischer, Tillmann G. A1 - Friedrich, Pascal A1 - Glorious, Frank A1 - Golub, Benjamin A1 - Grathwol, Christoph A1 - Haag, Rainer A1 - Hunold, Johannes A1 - Jacob, Christoph A1 - Johannsen, Jochen A1 - Jollife, John A1 - Kast, Stefan A1 - Kettner, Carsten A1 - Kuhn, Stefan A1 - Lanza, Giacomo A1 - Lisec, Jan A1 - Manolikakes, Georg A1 - Mata, Ricardo A1 - Meiler, Jens A1 - Müller, Matthias A1 - Müller-Pfefferkorn, Ralph A1 - Ortmeyer, Jochen A1 - Patterson, Wendy A1 - Pleiss, Jürgen A1 - Riedel, Annalisa A1 - Riedel, Jens A1 - Schatzschneider, Ulrich A1 - Schuster, Leonie A1 - Seeberger, Peter A1 - Seibert, Johann-Nikolaus A1 - Stadler, Peter A1 - Zeitler, Kirsten T1 - Proposal NFDI4Chem 2025-2030 In the National Research Data Infrastructure (NFDI) — Our Vision: All Chemists Publish FAIR Data N2 - The first funding period of NFDI4Chem established a robust foundation for research data management (RDM) in chemistry by promoting FAIR data principles and creating a cohesive infrastructure to capture well-annotated data early in the lab through electronic lab notebooks (ELNs) and making this data available in public repositories. Key achievements include standardised data formats and metadata, a federated repository environment, and improved data visibility and accessibility. Training programs and outreach have significantly increased awareness and adoption of best RDM practices. In the second funding period, the consortium aims to advance these achievements by consolidating this infrastructure, developing a model for its sustainable maintenance and operation, and fostering cultural change for its widespread adoption. Goals include ensuring seamless data workflows from laboratories to open repositories, enhancing interoperability, and supporting innovative research through AI-ready data. The work plan is organised into six task areas (TAs). TA1 (Management) provides leadership and supports all other TAs in achieving their objectives. TA2 (Smart Lab) aims to develop a fully digital research environment, including an ELN as a modular platform. This environment will support data collection, management, storage, analysis, and sharing. Integrating devices and external resources will enable seamless data transfer to repositories. TA3 (Repositories) will consolidate the repository ecosystem. The goal is to integrate repositories into a federated system for better accessibility and interoperability, ensuring long-term data availability and sustainability. TA4 (Metadata, Data Standards, and Publication Standards) focuses on developing and promoting new data and metadata standards in an international community process. This includes applying ontologies to create a semantic foundation for linking research data, making it machine-readable and enabling knowledge graphs. TA5 (Community and Training) is dedicated to fostering a cultural shift towards digital chemistry through continuous engagement, collecting requirements, and providing extensive training and support through workshops and open education resources. It will promote FAIR-compliant machine learning applications, embedding RDM into academic curricula to ensure future scientists are well-versed in these practices. TA6 (Synergies and Cross-Cutting Topics) aims to enhance collaboration across NFDI consortia and beyond. This includes developing ontologies, terminology services, the search service, and other cross-cutting solutions, integrating these developments into existing infrastructure, enabling interdisciplinary data harmonisation and fostering machine learning applications. KW - Research Data Management KW - FAIR KW - Chemistry PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648540 DO - https://doi.org/10.3897/rio.11.e177037 SN - 2367-7163 VL - 11 SP - 1 EP - 100 PB - Pensoft Publishers AN - OPUS4-64854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steinhäuser, Lorin A1 - Piechotta, Christian A1 - Westphalen, Tanja A1 - Kaminski, Katja T1 - Evaluation, comparison and combination of molecularly imprinted polymer solid phase extraction and classical solid phase extraction for the preconcentration of endocrine disrupting chemicals from representative whole water samples N2 - Estrogens are endocrine disrupting chemicals and of high concerns due to demonstrated harmful effects on the environment and low effect levels. For monitoring and risk assessment, several estrogens were included in the "watch list" of the EU Water Framework Directive which sets very low environmental quality standard (EQS) levels for Estrone (E1) and 17β-Estradiol (E2) of 0.4 ng L−1 and for 17α-Ethinylestradiol (EE2) of 0.035 ng L−1 requiring sensitive detection methods, as well as extensive sample preparation. A sensitive, derivatization-free, isotope dilution calibration HPLC-MS/MS method for a panel of 5 selected estrogens (including the 3 estrogens of the EU WFD watchlist), and a procedure for the reproducible preparation of a representative whole water matrix including mineral water, humic acids and solid particulate matter are presented. These are used in a diligent comparison of classical solid phase extraction (SPE) on hydrophilic-lipophilic balanced (HLB) phase to SPE on an estrogen-specific molecularly imprinted polymer phase (MISPE) for ultra-trace levels of the analytes (1–10 ng L−1). Additionally, a two-step procedure combining HLB SPE disks followed by MISPE is evaluated. The tow-step procedure provides superior enrichment, matrix removal and sample throughput while maintaining comparable recovery rates to simple cartridge SPE. Estimated method quantification limits (MQLs) range from 0.109–0.184 ng L−1 and thus meet EQS-levels for E1 and E2, but not EE2. The representative whole water matrix provides a reproducible comparison of sample preparation methods and lays the foundation for a certified reference material for estrogen analysis. The presented method will serve as the basis for an extended validation study to assess its use for estrogen monitoring in the environment. KW - Estrogens KW - Whole water samples KW - Molecular imprinted polymers KW - EU-WFD PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-563547 DO - https://doi.org/10.1016/j.talo.2022.100163 SN - 2666-8319 VL - 6 SP - 1 EP - 5 PB - Elsevier B.V. CY - Amsterdam, Niederlande AN - OPUS4-56354 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sternbaek, L. A1 - Kimani, Martha Wamaitha A1 - Gawlitza, Kornelia A1 - Rurack, Knut A1 - Janicke, B. A1 - Alm, K. A1 - Gjörloff-Wingren, A. A1 - Eriksson, H. T1 - Molecularly Imprinted Polymers Exhibit Low Cytotoxic and Inflammatory Properties in Macrophages In Vitro N2 - Molecularly imprinted polymers (MIPs) against sialic acid (SA) have been developed as a detection tool to target cancer cells. Before proceeding to in vivo studies, a better knowledge of the overall effects of MIPs on the innate immune system is needed. The aim of this study thus was to exemplarily assess whether SA-MIPs lead to inflammatory and/or cytotoxic responses when administered to phagocytosing cells in the innate immune system. The response of monocytic/macrophage cell lines to two different reference particles, Alhydrogel and PLGA, was compared to their response to SA-MIPs. In vitro culture showed a cellular association of SA-MIPs and Alhydrogel, as analyzed by flow cytometry. The reference particle Alhydrogel induced secretion of IL-1b from the monocytic cell line THP-1, whereas almost no secretion was provoked for SA-MIPs. A reduced number of both THP-1 and RAW 264.7 cells were observed after incubation with SA-MIPs and this was not caused by cytotoxicity. Digital holographic cytometry showed that SA-MIP treatment affected cell division, with much fewer cells dividing. Thus, the reduced number of cells after SA-MIP treatment was not linked to SA-MIPs cytotoxicity. In conclusion, SA-MIPs have a low degree of inflammatory properties, are not cytotoxic, and can be applicable for future in vivo studies. KW - Molecularly imprinted polymers KW - Digital holographic cytometry KW - Cytotoxicity KW - Proinflammatory cytokines PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552250 DO - https://doi.org/10.3390/app12126091 SN - 2076-3417 VL - 12 IS - 12 SP - 1 EP - 16 PB - MDPI CY - Basel AN - OPUS4-55225 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stiegler, L. M. S. A1 - Wegner, Karl David A1 - Weigert, Florian A1 - Peukert, W. A1 - Resch-Genger, Ute A1 - Walter, J. T1 - Analysis of Giant-Shell CdSe/CdS Quantum Dots via Analytical Ultracentrifugation Combined with Spectrally Resolved Photoluminescence N2 - Knowledge of the structure–property relationships of functional nanomaterials, including, for example, their size- and composition-dependent photoluminescence (PL) and particle-to-particle variations, is crucial for their design and reproducibility. Herein, the Angstrom-resolution capability of an analytical ultracentrifuge combined with an in-line multiwavelength emission detection system (MWE-AUC) for measuring the sedimentation coefficient-resolved spectrally corrected PL spectra of dispersed nanoparticles is demonstrated. The capabilities of this technique are shown for giant-shell CdSe/CdS quantum dots (g-QDs) with a PL quantum yield (PL QY) close to unity capped with oleic acid and oleylamine ligands. The MWE-AUC PL measurements are calibrated and validated with certified fluorescence standards. The spectrally corrected and size-dependent PL spectra of the g-QDs derived from a single MWE-AUC experiment are then analyzed and compared with the results of single-particle spectroscopic studies, yielding the PL spectra, decay kinetics, and blinking behavior of individual g-QDs. This study underlines the vast potential of MWE-AUC with in-line optical detection for the characterization of advanced nanomaterials with a complex structure. KW - Quantum dots KW - Analytical ultracentrifugation KW - Photoluminescence KW - Advanced nanomaterial characterization KW - Calibrated fluorescence measurements KW - Reference materials PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624357 DO - https://doi.org/10.1002/smtd.202401700 SN - 2366-9608 SP - 1 EP - 7 PB - Wiley VHC-Verlag AN - OPUS4-62435 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stratulat, C. A1 - Ginghina, R. E. A1 - Bratu, A. E. A1 - Isleyen, A. A1 - Tunc, M. A1 - Hafner-Vuk, K. A1 - Frey, A. M. A1 - Kjeldsen, H. A1 - Vogl, Jochen T1 - Development- and Validation-Improved Metrological Methods for the Determination of Inorganic Impurities and Ash Content from Biofuels N2 - In this study, five laboratories, namely, BRML (Romania), TUBITAK UME (Turkey), IMBIH (Bosnia and Herzegovina), BAM (Germany), and DTI (Denmark), developed and validated analytical procedures by ICP-MS, ICP-OES, MWP-AES, WD-XRF, and ID-MS for the determination of inorganic impurities in solid and liquid biofuels, established the budget of uncertainties, and developed the method for determining the amount of ash in the measurement range 0–1.2% with absolute repeatability less than 0.1% and absolute reproducibility of 0.2% (according to EN ISO 18122). In order to create homogeneous certified reference materials, improved methodologies for the measurement and characterization of solid and liquid biofuels were developed. Thus, information regarding the precision, accuracy, and bias of the method, and identifying the factors that intervened in the measurement of uncertainty were experimentally determined, supplementing the information from the existing standards in the field. KW - Development KW - Validate method KW - Biodiesel KW - ICP-MS KW - ICP-OES KW - MW-AES KW - WD-XRF KW - ID-MS KW - Inorganic impurities KW - Ash content KW - Wood chips PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-578743 DO - https://doi.org/10.3390/en16135221 VL - 16 IS - 13 SP - 1 EP - 14 PB - MDPI AN - OPUS4-57874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sun, C. A1 - Schäferling, Michael A1 - Resch-Genger, Ute A1 - Gradzielski, M. T1 - Solvothermal Synthesis of Lanthanide-doped NaYF4 Upconversion N2 - Lanthanide-doped NaYF4 upconversion nano- and microcrystals were synthesized via a facile solvothermal approach. Thereby, the influence of volume ratios of ethylene glycol (EG)/H2O, molar ratios of NH4F/RE3+ (RE3+ represents the total amount of Y3+ and rare-earth dopant ions), Gd3+ ion contents, types of activator dopant ions, and different organic co-solvents on the crystal phase, size, and morphology of the resulting particles were studied systematically. A possible formation mechanism for the growth of crystals of different morphology is discussed. Our results show that the transition from the α- to the β-phase mainly depends on the volume ratio of EG/H2O and the molar ratio of NH4F/RE3+, while the morphology and size could be controlled by the type of organic co-solvent and Gd3+ dopant ions. Furthermore, the reaction time has to be long enough to convert α-NaYF4 into β-NaYF4 during the growth process to optimize the upconversion luminescence. The formation of larger β-NaYF4 crystals, which possess a higher upconversion luminescence than smaller particles, proceeds via intermediates of smaller crystals of cubic structure. In summary, our synthetic approach presents a facile route to tailor the size, Crystal phase, morphology, and luminescence features of upconversion materials. KW - Nano KW - Nanomaterial KW - Upconversion nanoparticle KW - Photoluminescence KW - Lanthanide KW - Quantum yield KW - Photophysics KW - Lifetime KW - Surface chemistry KW - Single particle KW - Brightness KW - NIR KW - Synthesis PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520307 DO - https://doi.org/10.1002/cnma.202000564 VL - 7 IS - 2 SP - 174 EP - 183 PB - Wiley AN - OPUS4-52030 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sun, Yijuan A1 - Gawlitza, Kornelia A1 - Valderrey, Virginia A1 - Bell, Jérémy A1 - Rurack, Knut T1 - Polymerizable BODIPY probe crosslinker for the molecularly imprinted polymer-based detection of organic carboxylates via fluorescence N2 - This contribution reports the development of a polymerizable BODIPY-type fluorescent probe targeting small-molecule carboxylates for incorporation into molecularly imprinted polymers (MIPs). The design of the probe crosslinker includes a urea recognition site p-conjugated to the 3-position of the BODIPY core and two methacrylate moieties. Titration experiments with a carboxylate-expressing antibiotic, levofloxacin (LEVO), showed a blue shift of the absorption band as well as a broadening and decrease in emission, attributed to hydrogen bonding between the probe’s urea group and the carboxylate group of the antibiotic. Using this probe crosslinker, core–shell particles with a silica core and a thin MIP shell were prepared for the detection of LEVO. The MIP exhibited highly selective recognition of LEVO, with an imprinting factor of 18.1 compared to the non-imprinted polymer. Transmission electron microscopy confirmed the core–shell structure and spectroscopic studies revealed that the receptor’s positioning leads to a unique perturbation of the polymethinic character of the BODIPY chromophore, entailing the favourable responses. These features are fully preserved in the MIP, whereas no such response was observed for competitors such as ampicillin. The sensory particles allowed to detect LEVO down to submicromolar concentrations in dioxane. We have developed here for the first time a BODIPY probe for organic carboxylates and incorporated it into polymers using the imprinting technique, paving the way for BODIPY-type fluorescent MIP sensors. KW - Fluorescence KW - BODIPY probe KW - Molecularly Imprinted Polymers KW - Sensor Materials KW - Dyes KW - Water analysis KW - Advanced materials PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598629 DO - https://doi.org/10.1039/D3MA00476G SP - 1 EP - 11 PB - Royal Society of Chemistry (RSC) AN - OPUS4-59862 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sun, Yijuan A1 - Gawlitza, Kornelia A1 - Valderrey, Virginia A1 - Bhattacharya, Biswajit A1 - Rurack, Knut T1 - Ratiometric Molecularly Imprinted Particle Probes for Reliable Fluorescence Signaling of Carboxylate-Containing Molecules N2 - In addition to sensitivity, selectivity, and portability, chemical sensing systems must generate reliable signals and offer modular configurability to address various small molecule targets, particularly in environmental applications. We present a versatile, modular strategy utilizing ratiometric molecularly imprinted particle probes based on BODIPY indicators and dyes for recognition and internal referencing. Our approach employs polystyrene core particles doped with a red fluorescent BODIPY as an internal standard, providing built-in reference for environmental influences. A molecularly imprinted polymer (MIP) recognition shell, incorporating a green-fluorescent BODIPY indicator monomer with a thiourea binding site for carboxylate containing analytes, is grafted from the core particles in the presence of the analyte as the template. The dual-fluorescent MIP probe detects fexofenadine as the model analyte with a change in green emission signal referenced against a stable red signal, achieving a detection limit of 0.13 μM and a broad dynamic range from 0.16 μM to 1.2 mM, with good discrimination against other antibiotics in acetonitrile. By selecting a versatile dye scaffold and recognition element, this approach can be extended to other carboxylate-containing analytes and/or wavelength combinations, potentially serving as a robust multiplexing platform. KW - Core-shell particles KW - Molecular imprinting KW - Pharmaceutical contaminants KW - Self-referenced measurements KW - Fluorescence PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-609385 DO - https://doi.org/10.1021/acsami.4c09990 SP - 1 EP - 13 PB - American Chemical Society (ACS) AN - OPUS4-60938 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sun, Yijuan A1 - Pérez-Padilla, Víctor A1 - Valderrey, Virginia A1 - Bell, Jérémy A1 - Gawlitza, Kornelia A1 - Rurack, Knut T1 - Ratiometric detection of perfluoroalkyl carboxylic acids using dual fluorescent nanoparticles and a miniaturised microfluidic platform N2 - The widespread contamination of soil and water with perfluoroalkyl substances (PFAS) has caused considerable societal and scientific concern. Legislative measures and an increased need for remediation require effective on-site analytical methods for PFAS management. Here we report on the development of a green-fluorescent guanidine-BODIPY indicator monomer incorporated into a molecularly imprinted polymer (MIP) for the selective detection of perfluorooctanoic acid (PFOA). Complexation of PFOA by the indicator, which is mediated by concerted protonation-induced ion pairing-assisted hydrogen bonding, significantly enhances fluorescence in polar organic solvents. The MIP forms as a thin layer on silica nanoparticles doped with tris(bipyridine)ruthenium(II) chloride, which provides an orange emission signal as internal reference, resulting in low measurement uncertainties. Using a liquid-liquid extraction protocol, this assay enables the direct detection of PFOA in environmental water samples and achieves a detection limit of 0.11 µM. Integration into an opto-microfluidic system enables a compact and user-friendly system for detecting PFOA in less than 15 minutes. KW - PFAS KW - Molecular imprinting KW - Microfluidics KW - Fluorescence KW - Onsite assay PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-650270 DO - https://doi.org/10.1038/s41467-025-66872-9 SN - 2041-1723 VL - 16 IS - 1 SP - 1 EP - 16 PB - Springer Science and Business Media LLC AN - OPUS4-65027 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tang, Chi-Long A1 - Seeger, Stefan T1 - Measurement of sub-4 nm particle emission from FFF-3D printing with the TSI Nano Enhancer and the Airmodus Particle Size Magnifier N2 - The emission of ultrafine particles from small desktop Fused Filament Fabrication (FFF) 3D printers has been frequently investigated in the past years. However, the vast majority of FFF emission and exposure studies have not considered the possible occurrence of particles below the typical detection limit of Condensation Particle Counters and could have systematically underestimated the total particle emission as well as the related exposure risks. Therefore, we comparatively measured particle number concentrations and size distributions of sub-4 nm particles with two commercially available diethylene glycol-based instruments – the TSI 3757 Nano Enhancer and the Airmodus A10 Particle Size Magnifier. Both instruments were evaluated for their suitability of measuring FFF-3D printing emissions in the sub-4 nm size range while operated as a particle counter or as a particle size spectrometer. For particle counting, both instruments match best when the Airmodus system was adjusted to a cut-off of 1.5 nm. For size spectroscopy, both instruments show limitations due to either the fast dynamics or rather low levels of particle emissions from FFF-3D printing in this range. The effects are discussed in detail in this article. The findings could be used to implement sub-4 nm particle measurement in future emission or exposure studies, but also for the development of standard test protocols for FFF-3D printing emissions. KW - Air pollution KW - Ultrafine particles KW - Sub-4nm particles KW - FFF-3D printing KW - Emission testing PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595952 DO - https://doi.org/10.1080/02786826.2024.2320430 SN - 0278-6826 VL - 58 IS - 6 SP - 644 EP - 656 PB - Taylor & Francis CY - London AN - OPUS4-59595 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tang, Chi-Long A1 - Seeger, Stefan A1 - Röllig, Mathias T1 - Improving the comparability of FFF-3D printing emission data by adjustment of the set extruder temperature N2 - Fused filament fabrication (FFF) is a material extrusion-based technique often used in desktop 3D printers. Polymeric filaments are melted and are extruded through a heated nozzle to form a 3D object in layers. The extruder temperature is therefore a key parameter for a successful print job but also one of the main emission driving factors as harmful pollutants (e.g., ultrafine particles) are formed by thermal polymer degradation. The awareness of potential health risks has increased the number of emission studies in the past years. However, studies usually refer their calculated emission data to the printer set extruder temperature for comparison purposes. In this study, we used a thermocouple and an infrared camera to measure the actual extruder temperature and found significant temperature deviations to the displayed set temperature among printer models. Our result shows that printing the same filament feedstocks with three different printer models and with identical printer set temperature resulted in a variation in particle emission of around two orders of magnitude. A temperature adjustment has reduced the variation to approx. one order of magnitude. Thus, it is necessary to refer the measured emission data to the actual extruder temperature as it poses a more accurate comparison parameter for evaluation of the indoor air quality in user scenarios or for health risk assessments. KW - Ultrafine particles KW - Infrared thermography KW - Thermocouple KW - Indoor air quality KW - FFF-3D printer PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572842 DO - https://doi.org/10.1016/j.aeaoa.2023.100217 VL - 18 SP - 100217 PB - Elsevier Ltd. CY - Amsterdam, Niederlande AN - OPUS4-57284 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tannenberg, Robert A1 - Paul, Martin A1 - Röder, Bettina A1 - Gande, S. L. A1 - Sreeramulu, S. A1 - Saxena, K. A1 - Richter, C. A1 - Schwalbe, H. A1 - Swart, C. A1 - Weller, Michael G. T1 - Chemiluminescence biosensor for the determination of cardiac troponin I (cTnI) N2 - Cardiac troponin I (cTnI) is a crucial biomarker for diagnosing cardiac vascular diseases, including acute myocardial infarction (AMI). This study presents a proof-of-concept chemiluminescence-based immunosensor for rapid and accurate measurement of cTnI, with the potential for online monitoring. The immunosensor incorporates a flow cell design and a sensitive complementary metal-oxide-semiconductor (CMOS) camera for optical readout. A microfluidic setup was established to enable selective and quasi-online determination of cTnI within ten minutes. The sensor was tested with recombinant cTnI in phosphate buffer, demonstrating measurements in the concentration range of 2–25 µg/L, with a limit of detection (LoD) of 0.6 µg/L (23 pmol/L) achieved using the optimized system. The immunosensor exhibited high selectivity, as no cross-reactivity was observed with other recombinant proteins such as cTnT and cTnC at a concentration of 16 µg/L. Measurements with diluted blood plasma and serum yielded an LoD of 60 µg/L (2.4 nmol/L) and 70 µg/L (2.9 nmol/L), respectively. This biosensor offers a promising approach for the rapid and sensitive detection of cTnI, contributing to the diagnosis and management of acute myocardial infarction and other cardiac vascular diseases. N2 - Das kardiale Troponin I (cTnI) ist ein wichtiger Biomarker für die Diagnose von Herz-Kreislauf-Erkrankungen, einschließlich des akuten Myokardinfarkts (AMI). In dieser Studie wird ein auf Chemilumineszenz basierender Immunsensor für die schnelle und genaue Messung von cTnI vorgestellt, der das Potenzial für eine Online-Überwachung hat. Der Immunsensor besteht aus einer Durchflusszelle und einer empfindlichen CMOS-Kamera (Complementary Metal-Oxide-Semiconductor) zur optischen Detektion. Es wurde ein mikrofluidischer Aufbau entwickelt, der eine selektive und quasi Online-Bestimmung von cTnI innerhalb von zehn Minuten ermöglicht. Der Sensor wurde mit rekombinantem cTnI in Phosphatpuffer getestet und zeigte einen Messbereich von 2-25 µg/L, wobei mit dem optimierten System eine Nachweisgrenze (LoD) von 0,6 µg/L (23 pmol/L) erreicht wurde. Der Immunsensor zeigte eine hohe Selektivität, da keine Kreuzreaktivität mit anderen rekombinanten Proteinen wie cTnT und cTnC bei einer Konzentration von 16 µg/L beobachtet wurde. Messungen mit verdünntem Blutplasma und Serum ergaben einen LoD von 60 µg/L (2,4 nmol/L) bzw. 70 µg/L (2,9 nmol/L). Dieser Biosensor bietet einen vielversprechenden Ansatz für den schnellen und empfindlichen Nachweis von cTnI, der zur Diagnose und Behandlung des akuten Myokardinfarkts und anderer kardialer Gefäßerkrankungen beitragen kann. KW - Acute myocardial infarction KW - Heart attack KW - Emergency KW - Diagnosis KW - Cardiac troponin KW - Biomarker KW - Immunosensor KW - Biosensor KW - Chemiluminescence KW - Luminol KW - Peroxidase KW - Monoclonal antibodies KW - Flow injection immunoassay KW - Immunometric assay KW - Immunometric biosensor KW - Microfluidic system KW - Monolithic column KW - Online biosensor PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575471 DO - https://doi.org/10.3390/bios13040455 SN - 2079-6374 VL - 13 IS - 4 SP - 1 EP - 20 PB - MDPI CY - Basel AN - OPUS4-57547 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tatzel, M. A1 - Frings, P. J. A1 - Oelze, Marcus A1 - Herwartz, D. A1 - Lünsdorf, K. A1 - Wiedenbeck, M. T1 - Chert oxygen isotope ratios are driven by Earth's thermal evolution N2 - The 18O/16O ratio of cherts (δ18Ochert) increases nearly monotonically by ~15‰ from the Archean to present. Two end-member explanations have emerged: cooling seawater temperature (TSW) and increasing seawater δ18O (δ18Osw). Yet despite decades of work, there is no consensus, leading some to view the δ18Ochert record as pervasively altered. Here, we demonstrate that cherts are a robust archive of diagenetic temperatures, despite metamorphism and exposure to meteoric fluids, and show that the timing and temperature of quartz precipitation and thus δ18Ochert are determined by the kinetics of silica diagenesis. A diagenetic model shows that δ18Ochert is influenced by heat flow through the sediment column. Heat flow has decreased over time as planetary heat is dissipated, and reasonable Archean-modern heat flow changes account for ~5‰ of the increase in δ18Ochert, obviating the need for extreme TSW or δ18Osw reconstructions. The seawater oxygen isotope budget is also influenced by solid Earth cooling, with a recent reconstruction placing Archean δ18OSW 5 to 10‰ lower than today. Together, this provides an internally consistent view of the δ18Ochert record as driven by solid Earth cooling over billion-year timescales that is compatible with Precambrian glaciations and biological. KW - Climate KW - Oxygen isotope ratios KW - Silica diagenesis KW - Early Earth KW - Heat flow PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569359 DO - https://doi.org/10.1073/pnas.2213076119 SN - 0027-8424 VL - 119 IS - 51 SP - 1 EP - 7 PB - National Academy of Sciences CY - Washington, DC AN - OPUS4-56935 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tatzel, Michael A1 - Oelze, Marcus A1 - Frick, Daniel A. A1 - Di Rocco, Tommaso A1 - Liesegang, Moritz A1 - Stuff, Maria A1 - Wiedenbeck, Michael T1 - Silicon and oxygen isotope fractionation in a silicified carbonate rock N2 - Silicon isotope fractionation during silicification is poorly understood and impedes our ability to decipher paleoenvironmental conditions from Si isotopes in ancient cherts. To investigate isotope fractionation during silica-for-carbonate replacement we analyzed the microscale Si and O isotope composition in different silica phases in a silicified zebra dolostone as well as their bulk δ18O and Δ’17O compositions. The subsequent replacement of carbonate layers is mimicked by decreasing δ18O and δ30Si. The textural relationship and magnitude of Si and O isotope fractionation is best explained by near-quantitative silica precipitation in an open system with finite Si. A Rayleigh model for silicification suggests positive Ɛ30/28Si during silicification, conforming with predictions for isotope distribution at chemical equilibrium from ab-initio models. Application of the modelled Ɛ30Si-T relationship yields silicification temperatures of approx. 50°C. To reconcile the δ18Ochert composition with these temperatures, the δ18O of the fluid must have been between -2.5 and -4 ‰, compositions for which the quartz phases fall close to the oxygen equilibrium fractionation line in three-isotope space. Diagenetic silica replacement appears to occur in O and Si isotopic equilibrium allowing reconstructions of temperatures of silicification from Si isotopes and derive the δ18O composition of the fluid – a highly desired value needed for accurate reconstructions of the temperature- and δ18O histories of the oceans. KW - Silicon isotopes PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603430 DO - https://doi.org/10.1016/j.chemgeo.2024.122120 SN - 0009-2541 VL - 658 SP - 1 EP - 13 PB - Elsevier B.V. AN - OPUS4-60343 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tavernaro, Isabella A1 - Rajotte, Isabelle A1 - Thibeault, Marie-Pier A1 - Sander, Philipp C. A1 - Kodra, Oltion A1 - Lopinski, Gregory A1 - Radnik, Jörg A1 - Johnston, Linda J. A1 - Brinkmann, Andreas A1 - Resch-Genger, Ute T1 - Quantifying surface groups on aminated silica nanoparticles of different size, surface chemistry, and porosity with solution NMR, XPS, optical assays, and potentiometric titration N2 - We assessed the quantification of surface amino functional groups (FGs) for a large set of commercial and custom-made aminated silica nanoparticles (SiO2 NPs) with sizes of 20–100 nm, prepared with different sol–gel routes, different amounts of surface amino FGs, and different porosity with four methods providing different, yet connected measurands in a bilateral study of two laboratories, BAM and NRC, with the overall aim to develop standardizable measurements for surface FG quantification. Special emphasis was dedicated to traceable quantitative magnetic resonance spectroscopy (qNMR) performed with dissolved SiO2 NPs. For the cost efficient and automatable screening of the amount of surface amino FGs done in a first step of this study, the optical fluorescamine assay and a potentiometric titration method were utilized by one partner, i.e., BAM, yielding the amount of primary amino FGs accessible for the reaction with a dye precursor and the total amount of (de)protonatable FGs. These measurements, which give estimates of the minimum and maximum number of surface amino FGs, laid the basis for quantifying the amount of amino silane molecules with chemo-selective qNMR with stepwise fine-tuned workflows, involving centrifugation, drying, weighting, dissolution, measurement, and data evaluation steps jointly performed by BAM and NRC. Data comparability and relative standard deviations (RSDs) obtained by both labs were used as quality measures for method optimization and as prerequisites to identify method-inherent limitations to be later considered for standardized measurement protocols. Additionally, the nitrogen (N) to silicon (Si) ratio in the near-surface region of the SiO2 NPs was determined by both labs using X-ray photoelectron spectroscopy (XPS), a well established surface sensitive analytical method increasingly utilized for microparticles and nano-objects which is currently also in the focus of international standardization activities. Overall, our results underline the importance of multi-method characterization studies for quantifying FGs on NMs involving at least two expert laboratories for effectively identifying sources of uncertainty, validating analytical methods, and deriving NM structure–property relationships. KW - Advanced Materials KW - Amino Groups KW - Calibration KW - Characterization KW - Functional groups KW - Method Comparison KW - Nano Particle KW - Validation KW - XPS KW - Optical Assay KW - Quantification KW - Surface Analysis KW - Reference Materials KW - Synthesis KW - Fluorescence PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-649992 DO - https://doi.org/10.1039/d5na00794a VL - 7 IS - 21 SP - 6888 EP - 6900 PB - Royal Society of Chemistry AN - OPUS4-64999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tavernaro, Isabella A1 - Sander, P. C. A1 - Andresen, Elina A1 - Schedler, U. A1 - Resch-Genger, Ute T1 - Expanding the Toolbox of Simple, Cost-Efficient, and Automatable Methods for Quantifying Surface Functional Groups on Nanoparticles� Potentiometric Titration N2 - Measuring surface functional groups (FGs) on nanomaterials (NMs) is essential for designing dispersible and stable NMs with tailored and predictable functionality. FG screening and quantification also plays a critical role for subsequent processing steps, NM long-term stability, quality control of NM production, and risk assessment studies and enables the implementation of sustainable and safe(r)-by-design concepts. This calls for simple and cost-efficient methods for broadly utilized FGs that can be ideally automated to speed up FG screening, monitoring, and quantification. To expand our NM surface analysis toolbox, focusing on simple methods and broadly available, cost-efficient instrumentation, we explored a NM-adapted pH titration method with potentiometric and optical readout for measuring the total number of (de)protonable FGs on representatively chosen commercial and custom-made aminated silica nanoparticles (SiO2 NPs). The accuracy and robustness of our stepwise optimized workflows was assessed by several operators in two laboratories and method validation was done by cross-comparison with two analytical methods relying on different signal generation principles. This included traceable, chemo-selective quantitative nuclear magnetic resonance spectroscopy (qNMR) and thermogravimetric analysis (TGA), providing the amounts of amino silanes released by particle dissolution and the total mass of the surface coatings. A comparison of the potentiometric titration results with the reporter-specific amounts of surface amino FGs determined with the previously automated fluorescamine (Fluram) assay highlights the importance of determining both quantities for surface-functionalized NMs. In the future, combined NM surface analysis with optical assays and pH titration will simplify quality control of NM production processes and stability studies and can yield large data sets for NM grouping that facilitates further developments in regulation and standardization. KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Synthesis KW - Characterization KW - Advanced material KW - Surface KW - Standardization KW - Reference material KW - Functional group KW - Quantification KW - Coating KW - Automation KW - Potentiometry KW - Method KW - Validation KW - Optical assay KW - Fluram KW - Fluorescamine KW - qNMR KW - Comparison KW - ILC PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-642371 DO - https://doi.org/10.1021/acsmeasuresciau.5c00062 SN - 2694-250X SP - 1 EP - 13 PB - American Chemical Society CY - Washington, DC AN - OPUS4-64237 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tavernaro, Isabella A1 - Simon, Fabian A1 - Gehrenkemper, Lennart A1 - Tobias, Charlie A1 - Resch-Genger, Ute A1 - Meermann, Björn T1 - Quantification of the amount of surface groups of aminated silica nano- and microparticles utilizing a fluorine tag and HR-CS-GFMAS N2 - The performance, bioavailability, and safe use of engineered nanomaterials (NMs) depends not only on properties such as size, shape, and surface area, but largely on surface chemistry. While many sizing methods have been established, there is still a lack of validated screening methods for determining NM surface functional groups (FGs). In this context, we present a fast and simple method for FG quantification using high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) and assess its applicability for the surface analysis of representatively chosen aminated silica nanoparticles (NPs) and microparticles (MPs) in conjunction with amino FG labeling with a fluorine tag. For this proof-of-concept study, first surface amino FG screening of the silica NPs and MPs was done with a potentiometric back titration method, providing the total amount of protonatable surface FGs, and two optical assays relying on reporter dyes with sizes and spatial requirements, i.e., surface binding areas smaller or larger than that of the fluorine tag to estimate the maximum and reporter-accessible number of amino FGs. Subsequently, the surface amino FGs were labeled with the fluorine tag 4-(trifluoromethyl)benzoic acid (TFMB) and the amount of fluorine originating from the bound TFMB molecules was quantified by HR-CS-GFMAS in two common organic solvents, i.e., dimethyl sulfoxide (DMSO) or ethanol (EtOH) to assess possible interferences from organic matrices. Our study revealed limits of detection (LODs) and quantification (LOQs) for fluorine of 1.0 µg/L and 3.5 µg/L in EtOH and 1.5 µg/L and 5.0 µg/L in DMSO, respectively. Overall, a quick and simple method for analyzing surface FGs on NPs and MPs was presented utilizing broadly available fluorine tags and HR-CS-GFMAS for fluorine quantification, which can be applied, e.g., for homogeneity, stability, and aging studies of surface-modified particles. This could contribute to ease the understanding of property-safety relationships for surface-functionalized NMs. KW - Fluorine Analysis KW - Nano- and microparticles KW - Surface group quantification PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641965 DO - https://doi.org/10.1007/s00216-025-06107-4 SN - 1618-2642 SP - 1 EP - 11 PB - Springer Science and Business Media LLC CY - Berlin ; Heidelberg AN - OPUS4-64196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tchipilov, Teodor A1 - Meyer, Klas A1 - Weller, Michael G. T1 - Quantitative 1H nuclear magnetic resonance (qNMR) of aromatic amino acids for protein quantification N2 - Hydrolysis of protein samples into amino acids facilitates the use of NMR spectroscopy for protein and peptide quantification. Different conditions have been tested for quantifying aromatic amino acids and proteins. The pH-dependent signal shifts in the aromatic region of amino acid samples were examined. A pH of 12 was found to minimize signal overlap of the four aromatic amino acids. Several aromatic compounds, such as terephthalic acid, sulfoisophthalic acid, and benzene tricarboxylic acid, were applied as internal standards. The quantification of amino acids from an amino acid standard was performed. Using the first two suggested internal standards, recovery was ~97% for histidine, phenylalanine, and tyrosine at a concentration of approximately 1 mM in solution. Acidic hydrolysis of a certified reference material (CRM) of bovine serum albumin (BSA) and subsequent quantification of Phe and Tyr yielded recoveries of 98% ± 2% and 88% ± 4%, respectively, at a protein concentration of 16 g/L or 250 µM. KW - Amino acid analysis KW - Aromatic amino acid analysis KW - AAA KW - AAAA KW - Protein hydrolysis KW - Hydrochloric acid KW - Metrology KW - Traceability KW - NIST KW - Reference materials KW - Internal standard KW - Calibration KW - Compound-independent calibration KW - Histidine KW - Tyrosine KW - Tryptophan KW - Phenylalanine KW - Terephthalic acid KW - Benzene-1,3,5-tricarboxylic acid KW - Bovine serum albumin (BSA) KW - Quantitative protein analysis KW - Phenylketonuria PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570943 DO - https://doi.org/10.3390/mps6010011 VL - 6 IS - 1 SP - 1 EP - 13 PB - MDPI CY - Basel, Schweiz AN - OPUS4-57094 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Temgoua, Ranil C.T. A1 - Dontsi, Fabiola T. A1 - Lebègue, Estelle A1 - Thobie-Gautier, Christine A1 - Tonlé, Ignas K. A1 - Boujtita, Mohammed T1 - Understanding the behavior of phenylurazole-tyrosine-click electrochemical reaction using hybrid electroanalytical techniques N2 - In this work, the electrochemical behavior of 4-phenylurazole (Ph-Ur) was studied and the latter was used as a molecular anchor for the electrochemical bioconjugation of tyrosine (Y). Cyclic voltammetry (CV) and controlled potential coulometry (CPC) allowed the in-situ generation of the PTAD (4-phenyl-3 H-1,2,4-triazole-3,5(4 H)-dione) species from phenylurazole on demand for tyrosine electrolabeling. The chemoselectivity of the reaction was studied with another amino acid (lysine, Lys) and no changes in Lys were observed. To evaluate the performance of tyrosine electrolabeling, coulometric analyses at controlled potentials were performed on solutions of phenylurazole and the phenylurazole-tyrosine mixture in different proportions (2:1, 1:1, and 1:2). The electrolysis of the phenylurazole-tyrosine mixture in the ratio (1:2) produced a charge of 2.07 C, very close to the theoretical value (1.93 C), with high reaction kinetics, a result obtained here for the first time. The products obtained were identified and characterized by liquid chromatography coupled to high-resolution electrospray ionization mass spectrometry (LC-HRMS and LC- HRMS2). Two products were formed from the click reactions, one of which was the majority. Another part of this work was to study the electrochemical degradation of the molecular anchor 4-phenylazole (Ph-Ur). Four stable degradation products of phenylurazole were identified (C7H9N2O, C6H8N, C6H8NO, C14H13N4O2) based on chromatographic profiles and mass spectrometry results. The charge generated during the electrolysis of phenylurazole (two-electron process) (2.85 C) is inconsistent with the theoretical or calculated charge (1.93 C), indicating that secondary/parasitic reactions occurred during the electrolysis of the latter. In conclusion, the electrochemically promoted click phenylurazole-tyrosine reactions give rise to click products with high reaction kinetics and yields in the (1:2) phenylurazole-tyrosine ratios, and the presence of side reactions is likely to affect the yield of the click phenylurazole-tyrosine reaction. KW - Clinical Biochemistry KW - Spectroscopy KW - Drug Discovery KW - Pharmaceutical Science KW - Analytical Chemistry PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599267 DO - https://doi.org/10.1016/j.jpba.2024.116147 VL - 245 SP - 1 EP - 8 PB - Elsevier BV AN - OPUS4-59926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thiele, Isabel A1 - Santolin, Lara A1 - Meyer, Klas A1 - Machatschek, Rainhard A1 - Bölz, Uwe A1 - Tarazona, Natalia A. A1 - Riedel, Sebastian L. T1 - Microbially synthesized poly(hydroxybutyrate-co-hydroxyhexanoate) with low to moderate hydroxyhexanoate content: Properties and applications N2 - Plastic pollution is the biggest environmental concern of our time. Breakdown products like micro- and nanoplastics inevitably enter the food chain and pose unprecedented health risks. In this scenario, bio-based and biodegradable plastic alternatives have been given a momentum aiming to bridge a transition towards a more sustainable future. Polyhydroxyalkanoates (PHAs) are one of the few thermoplastic polymers synthesized 100 % via biotechnological routes which fully biodegrade in common natural environments. Poly(hydroxybutyrate-cohydroxyhexanoate) [P(HB-co-HHx)] is a PHA copolymer with great potential for the commodity polymers industry, as its mechanical properties can be tailored through fine-tuning of its molar HHx content. We have recently developed a strategy that enables for reliable tailoring of the monomer content of P(HB-co-HHx). Nevertheless, there is often a lack of comprehensive investigation of the material properties of PHAs to evaluate whether they actually mimic the functionalities of conventional plastics. We present a detailed study of P(HB-co-HHx) copolymers with low to moderate hydroxyhexanoate content to understand how the HHx monomer content influences the thermal and mechanical properties and to link those to their abiotic degradation. By increasing the HHx fractions in the range of 2 – 14 mol%, we impart an extension of the processing window and application range as the melting temperature (Tm) and glass temperature (Tg) of the copolymers decrease from Tm 165 ◦C to 126 ◦C, Tg 4 ◦C to − 5.9 ◦C, accompanied by reduced crystallinity from 54 % to 20 %. Elongation at break was increased from 5.7 % up to 703 % at 14 mol% HHx content, confirming that the range examined was sufficiently large to obtain ductile and brittle copolymers, while tensile strength was maintained throughout the studied range. Finally, accelerated abiotic degradation was shown to be slowed down with an increasing HHx fraction decreasing from 70 % to 55 % in 12 h. KW - Molecular Biology KW - General Medicine KW - Biochemistry KW - Structural Biology PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595636 DO - https://doi.org/10.1016/j.ijbiomac.2024.130188 VL - 263 SP - 1 EP - 9 PB - Elsevier B.V. AN - OPUS4-59563 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thiele, Isabel A1 - Weiske, Björn A1 - Riedel, Sebastian L. A1 - Meyer, Klas T1 - On-line monitoring of polyhydroxyalkanoate extraction by low-field nuclear magnetic resonance spectroscopy N2 - The use of low-field nuclear magnetic resonance (NMR) spectroscopy enables real-time reaction monitoring in contrast to time-consuming gas chromatography or off-line high-field NMR measurements. In this study, NMR spectroscopy is demonstrated as a novel process analytical technology (PAT) tool in the downstream processing of polyhydroxyalkanoate (PHA) biopolymers. On-line NMR spectroscopy measurements were performed using a Spinsolve 43 Carbon Ultra instrument in a fully automated mode with a flow-assembly based on PTFE tubing. Single-scan NMR spectra were acquired for real-time monitoring of the extraction process of the PHA copolymer poly(hydroxybutyrate-co-hydroxyhexanoate) with 13.5 mol.% hydroxyhexanoate [P(HB-co-13.5 mol.%HHx)] from Ralstonia eutropha biomass using chloroform or acetone as PHA solvents at lyophilized cell loadings of 20–120 g L􀀀 1. The reproducibility and reliability of low-field NMR spectroscopy was comparable to high-field NMR spectroscopy, with superior performance in terms of time. The correlation between the results of on-line monitoring using low-field NMR spectroscopy and off-line analysis using gas chromatography (GC) showed a correlation coefficient of >94 %. The versatility of low-field NMR spectroscopy for elucidating reaction kinetics, facilitating endpoint determination and accelerating extraction processes by maximizing solubility is highlighted as plateau values were reached within 6–10 min for chloroform and acetone, respectively. This novel low-field NMR spectroscopy application promotes a new monitoring approach for downstream PHA processing and supports process development and optimization. KW - Polyhydroxyalkanoate KW - Extraction KW - NMR KW - Ralstonia eutropha KW - Downstream processing PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624215 DO - https://doi.org/10.1016/j.polymdegradstab.2025.111188 SN - 1873-2321 VL - 233 SP - 1 EP - 10 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-62421 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tjaden, B. A1 - Lisec, Jan A1 - Schramm, A. T1 - N-Myc-induced metabolic rewiring creates novel therapeutic vulnerabilities in neuroblastoma N2 - N-Myc is a transcription factor that is aberrantly expressed in many tumor types and is often correlated with poor patient prognosis. Recently, several lines of evidence pointed to the fact that oncogenic activation of Myc family proteins is concomitant with reprogramming of tumor cells to cope with an enhanced need for metabolites during cell growth. These adaptions are driven by the ability of Myc proteins to act as transcriptional amplifiers in a tissue-of-origin specific manner. Here, we describe the effects of N-Myc overexpression on metabolic reprogramming in neuroblastoma cells. Ectopic expression of N-Myc induced a glycolytic switch that was concomitant with enhanced sensitivity towards 2-deoxyglucose, an inhibitor of glycolysis. Moreover, global metabolic profiling revealed extensive alterations in the cellular metabolome resulting from overexpression of N-Myc. Limited supply with either of the two main carbon sources, glucose or glutamine, resulted in distinct shifts in steady-state metabolite levels and significant changes in glutathione metabolism. Interestingly, interference with glutamine-glutamate conversion preferentially blocked proliferation of N-Myc overexpressing cells, when glutamine levels were reduced. Thus, our study uncovered N-Myc induction and nutrient levels as important metabolic master switches in neuroblastoma cells and identified critical nodes that restrict tumor cell proliferation. KW - Mass-Spectrometry KW - Cancer KW - MYCN PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507193 DO - https://doi.org/10.1038/s41598-020-64040-1 VL - 10 IS - 1 SP - 7157 AN - OPUS4-50719 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tobias, Charlie A1 - Gehrenkemper, Lennart A1 - Bernstein, Thomas A1 - Schlau, Sven A1 - Simon, Fabian A1 - Röllig, Mathias A1 - Meermann, Björn A1 - von der Au, Marcus T1 - Development of a fully automated slurry sampling introduction system for GF-AAS and its application for the determination of cadmium in different matrices N2 - element analysis, offering high sensitivity and precision. However, its effectiveness is limited by sample preparation challenges for solid samples like soils and microplastics. Traditional methods include sample preparation, such as digestion, which is time-consuming and involves reagents, like acids, contributing to measurement uncertainty and higher carbon footprints. Slurry sampling allows direct analysis of suspensions, offering a more efficient alternative. However, maintaining suspension stability is challenging, requiring robust autosampler systems to streamline the process and enhance analytical performance. Results: We present a novel autosampler extension for slurry sample introduction into GF-AAS. This system ensures suspension stability with a stirring device and closed vessels to prevent evaporation and contamination, incorporating a cooling unit to reduce solvent and analyte losses. It installs and removes in minutes without additional connections. Validation with cadmium analysis in BAM-U110 (Soil) and BAM-H010 (ABS) showed high reliability. For BAM-U110 (Soil), we achieved recovery rates of 94 % ± 13 % in water suspension. The recovery rate for BAM-H010 (ABS) was 104 % ±11 % in acetonitrile suspension. These results demonstrate the system’s robustness, versatility, and accuracy for different matrices. Significance: The autosampler extension helps solve key problems in trace element analysis of solid samples, making the process faster and more accurate. It works well with complex materials, making it useful for areas like microplastic or nanoparticle analysis. This improvement also helps meet regulations for monitoring environ mental and polymer samples, offering a reliable and flexible tool for high-throughput analysis with fewer errors. KW - Slurry AAS KW - Soil KW - Cd PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618531 DO - https://doi.org/10.1016/j.aca.2024.343460 SN - 0003-2670 VL - 1335 SP - 1 EP - 7 PB - Elsevier BV AN - OPUS4-61853 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tobias, Charlie A1 - López-Puertollano, Daniel A1 - Abad-Somovilla, Antonio A1 - Mercader, J. V. A1 - Abad-Fuentes, A. A1 - Rurack, Knut T1 - Development of Simple and Rapid Bead-Based Cytometric Immunoassays Using Superparamagnetic Hybrid Core−Shell Microparticles N2 - Flow cytometry-based immunoassays are valuable in biomedical research and clinical applications due to their high throughput and multianalyte capability, but their adoption in areas such as food safety and environmental monitoring is limited by long assay times and complex workflows. Rapid, simplified bead-based cytometric immunoassays are needed to make these methods viable for point-of-need applications, especially with the increasing accessibility of miniaturized cytometers. This work introduces superparamagnetic hybrid polystyrene-silica core−shell microparticles as promising alternatives to conventional polymer beads in competitive cytometric immunoassays. These beads, featuring high specificity, sensitivity, and excellent handling capabilities via magnetic separation, were evaluated with three different antibodies and binding methods, showing variations in signal intensity based on the antibody and its attachment method. The optimal performance was achieved through a secondary antibody binding approach, providing strong and consistent signals with minimal uncertainty. The optimized protocol made it possible to achieve a detection limit of 0.025 nM in a total assay time of only 15 min and was successfully used to detect ochratoxin A (OTA) in raw flour samples. This work highlights the potential of these beads as versatile tools for flow cytometry-based immunoassays, with significant implications for food safety, animal health, environmental monitoring, and clinical diagnostics. KW - Immunoassays KW - Bead-based KW - Core-shell particles KW - Cytometry KW - Mycotoxins PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610593 DO - https://doi.org/10.1021/acsmeasuresciau.4c00038 SP - 1 EP - 11 PB - American Chemical Society CY - Washington, D.C. AN - OPUS4-61059 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tscheuschner, Georg A1 - Kaiser, Melanie N. A1 - Lisec, Jan A1 - Beslic, D. A1 - Muth, Thilo A1 - Krüger, M. A1 - Mages, H. W. A1 - Dorner, B. G. A1 - Knospe, J. A1 - Schenk, J. A. A1 - Sellrie, F. A1 - Weller, Michael G. T1 - MALDI-TOF-MS-Based Identification of Monoclonal Murine Anti-SARS-CoV-2 Antibodies within One Hour N2 - During the SARS-CoV-2 pandemic, many virus-binding monoclonal antibodies have been developed for clinical and diagnostic purposes. This underlines the importance of antibodies as universal bioanalytical reagents. However, little attention is given to the reproducibility crisis that scientific studies are still facing to date. In a recent study, not even half of all research antibodies mentioned in publications could be identified at all. This should spark more efforts in the search for practical solutions for the traceability of antibodies. For this purpose, we used 35 monoclonal antibodies against SARS-CoV-2 to demonstrate how sequence-independent antibody identification can be achieved by simple means applied to the protein. First, we examined the intact and light chain masses of the antibodies relative to the reference material NIST-mAb 8671. Already half of the antibodies could be identified based solely on these two parameters. In addition, we developed two complementary peptide mass fingerprinting methods with MALDI-TOF-MS that can be performed in 60 min and had a combined sequence coverage of over 80%. One method is based on the partial acidic hydrolysis of the protein by 5 mM of sulfuric acid at 99 degrees C. Furthermore, we established a fast way for a tryptic digest without an alkylation step. We were able to show that the distinction of clones is possible simply by a brief visual comparison of the mass spectra. In this work, two clones originating from the same immunization gave the same fingerprints. Later, a hybridoma sequencing confirmed the sequence identity of these sister clones. In order to automate the spectral comparison for larger libraries of antibodies, we developed the online software ABID 2.0. This open-source software determines the number of matching peptides in the fingerprint spectra. We propose that publications and other documents critically relying on monoclonal antibodies with unknown amino acid sequences should include at least one antibody fingerprint. By fingerprinting an antibody in question, its identity can be confirmed by comparison with a library spectrum at any time and context. KW - Reproducibility KW - Quality control KW - Traceability KW - Peptides KW - Peptide mass fingerprinting KW - Monoclonal antibody KW - Recombinant antibody KW - Identity KW - Antibody identification KW - Sequencing KW - Light chain KW - Mass spectrometry KW - Software KW - Open science KW - Library KW - COVID-19 KW - Corona virus KW - Sequence coverage KW - NIST-mAb 8671 KW - Reference material KW - RBD KW - Spike protein KW - Nucleocapsid KW - Cleavage KW - Tryptic digest KW - MALDI KW - DHAP KW - 2,5-dihydroxyacetophenone KW - Github KW - Zenodo KW - ABID PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547347 DO - https://doi.org/10.3390/antib11020027 VL - 11 IS - 2 SP - 1 EP - 22 PB - MDPI CY - Basel AN - OPUS4-54734 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tscheuschner, Georg A1 - Ponader, Marco A1 - Raab, Christopher A1 - Weider, Prisca S. A1 - Hartfiel, Reni A1 - Kaufmann, Jan Ole A1 - Völzke, Jule L. A1 - Bosc-Bierne, Gaby A1 - Prinz, Carsten A1 - Schwaar, T. A1 - Andrle, Paul A1 - Bäßler, Henriette A1 - Nguyen, Khoa A1 - Zhu, Y. A1 - Mey, A. S. J. S. A1 - Mostafa, A. A1 - Bald, I. A1 - Weller, Michael G. T1 - Efficient Purification of Cowpea Chlorotic Mottle Virus by a Novel Peptide Aptamer N2 - The cowpea chlorotic mottle virus (CCMV) is a plant virus explored as a nanotechnological platform. The robust self-assembly mechanism of its capsid protein allows for drug encapsulation and targeted delivery. Additionally, the capsid nanoparticle can be used as a programmable platform to display different molecular moieties. In view of future applications, efficient production and purification of plant viruses are key steps. In established protocols, the need for ultracentrifugation is a significant limitation due to cost, difficult scalability, and safety issues. In addition, the purity of the final virus isolate often remains unclear. Here, an advanced protocol for the purification of the CCMV from infected plant tissue was developed, focusing on efficiency, economy, and final purity. The protocol involves precipitation with PEG 8000, followed by affinity extraction using a novel peptide aptamer. The efficiency of the protocol was validated using size exclusion chromatography, MALDI-TOF mass spectrometry, reversed-phase HPLC, and sandwich immunoassay. Furthermore, it was demonstrated that the final eluate of the affinity column is of exceptional purity (98.4%) determined by HPLC and detection at 220 nm. The scale-up of our proposed method seems to be straightforward, which opens the way to the large-scale production of such nanomaterials. This highly improved protocol may facilitate the use and implementation of plant viruses as nanotechnological platforms for in vitro and in vivo applications. N2 - Das Cowpea Chlorotic Mottle Virus (CCMV) ist ein Pflanzenvirus, das als nanotechnologische Plattform erforscht wird. Der robuste Selbstorganisationsmechanismus seines Kapsidproteins ermöglicht die Verkapselung und gezielte Abgabe von Medikamenten. Darüber hinaus kann das Kapsid-Nanopartikel als programmierbare Plattform für die Präsentation verschiedener molekularer Komponenten verwendet werden. Im Hinblick auf künftige Anwendungen ist eine effiziente Produktion und Reinigung von Pflanzenviren von entscheidender Bedeutung. In etablierten Protokollen stellt die notwendige Ultrazentrifugation aufgrund von Kosten, schwieriger Skalierbarkeit und Sicherheitsaspekten eine erhebliche Einschränkung dar. Darüber hinaus bleibt die Reinheit des endgültigen Virusisolats oft unklar. Hier wurde ein fortschrittliches Protokoll für die Reinigung von CCMV aus infiziertem Pflanzengewebe entwickelt, wobei der Schwerpunkt auf Effizienz, Wirtschaftlichkeit und Reinheit lag. Das Protokoll beinhaltet eine Fällung mit Polyethylenglycol (PEG 8000), gefolgt von einer Affinitätsextraktion mit einem neuartigen Peptid-Aptamer. Die Effizienz des Protokolls wurde mithilfe von Größenausschluss-Chromatographie (SEC), MALDI-TOF-Massenspektrometrie, Umkehrphasen-HPLC und Sandwich-Immunoassay validiert. Darüber hinaus wurde nachgewiesen, dass das endgültige Eluat der Affinitätssäule eine außergewöhnliche Reinheit (98,4 %) aufweist, die durch HPLC und Detektion bei 220 nm bestimmt wurde. Die Skalierung der von uns vorgeschlagenen Methode scheint einfach zu sein, was den Weg für eine größer angelegte Produktion solcher Nanomaterialien ebnet. Dieses stark verbesserte Protokoll könnte die Verwendung und Umsetzung von Pflanzenviren als nanotechnologische Plattformen für In-vitro- und In-vivo-Anwendungen erleichtern. KW - Affinity chromatography KW - Nanoparticles KW - Nanoscience KW - Carrier protein KW - Encapsulation KW - Combinatorial peptide library KW - Peptide binder KW - Vigna unguiculata KW - Augenbohne KW - Schlangenbohne KW - Pflanzenvirus KW - Plant virus KW - Upscaling KW - Commercialization KW - Reference material KW - Nanocarrier PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572645 DO - https://doi.org/10.3390/v15030697 VL - 15 IS - 3 SP - 1 EP - 24 PB - MDPI CY - Basel, Schweiz AN - OPUS4-57264 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tscheuschner, Georg A1 - Schwaar, Timm A1 - Weller, Michael G. T1 - Fast Confirmation of Antibody Identity by MALDI-TOF MS Fingerprints N2 - Thousands of antibodies for diagnostic and other analytical purposes are on the market. However, it is often difficult to identify duplicates, reagent changes, and to assign the correct original publications to an antibody. This slows down scientific progress and might even be a cause of irreproducible research and a waste of resources. Recently, activities were started to suggest the sole use of recombinant antibodies in combination with the open communication of their sequence. In this case, such uncertainties should be eliminated. Unfortunately, this approach seems to be rather a long-term vision since the development and manufacturing of recombinant antibodies remain quite expensive in the foreseeable future. Nearly all commercial antibody suppliers also may be reluctant to publish the sequence of their antibodies, since they fear counterfeiting. De novo sequencing of antibodies is also not feasible today for a reagent user without access to the hybridoma clone. Nevertheless, it seems to be crucial for any scientist to have the opportunity to identify an antibody undoubtedly to guarantee the traceability of any research activity using antibodies from a third party as a tool. For this purpose, we developed a method for the identification of antibodies based on a MALDI-TOF MS fingerprint. To circumvent lengthy denaturation, reduction, alkylation, and enzymatic digestion steps, the fragmentation was performed with a simple formic acid hydrolysis step. Eighty-nine unknown monoclonal antibodies were used for this study to examine the feasibility of this approach. Although the molecular assignment of peaks was rarely possible, antibodies could be easily recognized in a blinded test, simply from their mass-spectral fingerprint. A general protocol is given, which could be used without any optimization to generate fingerprints for a database. We want to propose that, in most scientific projects relying critically on antibody reagents, such a fingerprint should be established to prove and document the identity of the used antibodies, as well as to assign a specific reagent to a datasheet of a commercial supplier, public database record, or antibody ID. KW - Reproducibility KW - Quality Control KW - Traceability KW - Diagnostics KW - Hybridoma KW - Monoclonal Antibody KW - Recombinant Antibody PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506611 DO - https://doi.org/10.3390/antib9020008 SN - 2073-4468 VL - 9 IS - 2 SP - 1 EP - 17 PB - MDPI CY - Basel AN - OPUS4-50661 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tukhmetova, Dariya A1 - Langhammer, Nicole A1 - Vogl, Jochen A1 - Meermann, Björn T1 - Online Isotope Analysis of Sulfur in Proteins via Capillary Electrophoresis Coupled With Multicollector ICP‐MS (CE/MC‐ICP‐MS): A Proof of Concept Study N2 - Isotope ratio analysis of sulfur in biological samples using inductively coupled plasma-mass spectrometry (ICP-MS) has gained significant interest for applications in quantitative proteomics. Advancements like coupling separation techniques with multicollector ICP-MS (MC-ICP-MS) enhance the throughput of species-specific sulfur isotope ratio measurements, fostering new avenues for studying sulfur metabolism in complex biological matrices. This proof-of-concept study investigates the feasibility of online CE/MC-ICP-MS for directly analyzing sulfur isotope ratios in proteins (albumin). Leveraging our previous work on the applicability of CE/ICP-MS for quantifying sulfur-containing biological molecules, we explore its potential for sulfur isotope analysis. Our results demonstrate that direct analysis of sulfur isotopes in albumin protein using online capillary electrophoresis MC-ICP-MS (CE/MC-ICP-MS) eliminates the need for laborious pretreatment steps, while yielding isotope ratios comparable to the reference values. Although initial precision can be improved through further system optimization and protein injection techniques, this approach paves the way for future analysis of mixtures of various biological compounds in, for example, clinical diagnosis studies. KW - Isotope analysis KW - Sulfur KW - CE/MC-ICP-MS PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612439 DO - https://doi.org/10.1002/elps.202400128 SN - 0173-0835 SP - 1 EP - 6 PB - Wiley-Blackwell CY - Weinheim AN - OPUS4-61243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tukhmetova, Dariya A1 - Lisec, Jan A1 - Vogl, Jochen A1 - Meermann, Björn T1 - Data processing made easy: standalone tool for automated calculation of isotope ratio from transient signals – IsoCor N2 - Despite numerous advantages offered by hyphenation of chromatography and electrokinetic separation methods with multicollector (MC) ICP-MS for isotope analysis, the main limitation of such systems is the decrease in precision and increase in uncertainty due to generation of short transient signals. To minimize this limitation, most authors compare several isotope ratio calculation methods and establish a multi-step data processing routine based on the precision and accuracy of the methods. However, to the best of our knowledge, there is no universal data processing tool available that incorporates all important steps of the treatment of the transient signals. Thus, we introduce a data processing application (App) IsoCor that facilitates automatic calculation of isotope ratios from transient signals and eases selection of the most suitable method. The IsoCor App performs baseline subtraction, peak detection, mass bias correction, isotope ratio calculation and delta calculation. The feasibility and reliability of the App was proven by reproducing the results from isotope analysis of three elements (neodymium, mercury and sulfur) measured on-line via hyphenated systems. The IsoCor App provides trackability of the results to ensure quality control of the analysis. KW - Isotope ratio KW - Transient signal KW - MC-ICP-MS KW - Data processing KW - App PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559068 DO - https://doi.org/10.1039/D2JA00208F VL - 37 IS - 11 SP - 2401 EP - 2409 PB - Royal Society of Chemistry AN - OPUS4-55906 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tukhmetova, Dariya A1 - Lisec, Jan A1 - Vogl, Jochen A1 - Meermann, Björn T1 - Development of an Online Isotope Dilution CE/ICP–MS Method for the Quantification of Sulfur in Biological Compounds N2 - We report an analytical methodology for the quantification of sulfur in biological molecules via a speciesunspecific postcolumn isotope dilution (online ID) approach using capillary electrophoresis (CE) coupled online with inductively coupled plasma−mass spectrometry (online ID CE/ICP−MS). The method was optimized using a mixture of standard compounds including sulfate, methionine, cysteine, cystine, and albumin, yielding compound recoveries between 98 and 105%. The quantity of sulfur is further converted to the quantity of the compounds owing to the prior knowledge of the sulfur content in the molecules. The limit of detection and limit of quantification of sulfur in the compounds were 1.3−2.6 and 4.1−8.4 mg L−1, respectively, with a correlation coefficient of 0.99 within the concentration range of sulfur of 5−100 mg L−1. The capability of the method was extended to quantify albumin in its native matrix (i.e., in serum) using experimentally prepared serum spiked with a pure albumin standard for validation. The relative expanded uncertainty of the method for the quantification of albumin was 6.7% (k = 2). Finally, we tested the applicability of the method on real samples by the analysis of albumin in bovine and human sera. For automated data assessment, a software application (IsoCor) which was developed by us in a previous work was developed further for handling of online ID data. The method has several improvements compared to previously published setups: (i) reduced adsorption of proteins onto the capillary wall owing to a special capillary-coating procedure, (ii) baseline separation of the compounds in less than 30 min via CE, (iii) quantification of several sulfur species within one run by means of the online setup, (iv) SI traceability of the quantification results through online ID, and (v) facilitated data processing of the transient signals using the IsoCor application. Our method can be used as an accurate approach for quantification of proteins and other biological molecules via sulfur analysis in complex matrices for various fields, such as environmental, biological, and pharmaceutical studies as well as clinical diagnosis. Sulfur is an essential element in living organisms, where it plays important roles in various biological processes, such as protein synthesis, enzyme activity, and antioxidant defense. However, the biological effects of different sulfur species can vary widely, and imbalances in sulfur speciation have been observed in a range of diseases, including cancer, Alzheimer’s disease, and diabetes.1−3 The accurate quantification of sulfur and its species in biological samples requires sensitive and selective analytical techniques. In recent years, separation techniques coupled online with inductively coupled plasma−mass spectrometry (ICP−MS) have emerged as powerful online analytical tools complementary to molecular spectrometric methods for speciation analysis of biological compounds. External calibration4−9 and isotope dilution (ID)10−15 are common calibration approaches applied for online quantification of sulfur species in complex samples. The ID analysis is advantageous over. KW - Analytical Chemistry KW - CE/MC-ICP-MS KW - species-specific isotope information PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594736 DO - https://doi.org/10.1021/acs.analchem.3c03553 SN - 0003-2700 SP - 1 EP - 8 PB - American Chemical Society (ACS) AN - OPUS4-59473 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tuma, Dirk A1 - Mady, A. H. A1 - Baynosa, M. L. A1 - Saad, M. A1 - Dhakal, G. A1 - Kim, W. K. A1 - Shim, Jae-Jin T1 - Morphology-engineered hollow NiTiO₃/C–Ag/Ag₃PO₄ S-scheme heterojunction photocatalyst: mechanistic insights into sunlight-driven tetracycline degradation N2 - Tetracycline (TCH), a widely used antibiotic, persists in aquatic and terrestrial environments, posing ecological risks and accelerating antibiotic resistance. To address this, we report a hollow-structured NiTiO₃/C–Ag/Ag₃PO₄ (NT/C–AAP) photocatalyst—the first hollow-type nickel titanate—synthesized via a self-template solvothermal route followed by photodeposition. The catalyst integrates key design strategies—hollow architecture, oxygen vacancies, carbon coating, and an S-scheme heterojunction—to optimize photocatalytic performance. The hollow structure enhances light harvesting via internal scattering, oxygen vacancies facilitate O2 adsorption and superoxide (O₂•⁻) generation, and the S-scheme heterojunction effectively suppresses electron–hole recombination while preserving strong redox potential. NT/C–AAP achieved 96% TCH degradation within 1 h and 82% mineralization in 3 h under solar light, far exceeding core–shell (18%) and aggregated (47%) NiTiO₃-based catalysts. Complete removal was realized within 40 min under 400 W visible light. The catalyst maintained 96% activity after five cycles, confirming excellent durability. Compared with previously reported NiTiO₃ photocatalysts, NT/C–AAP delivered a 50–400% performance enhancement arising from its engineered hollow structure and improved electronic properties. Mechanistic studies identified O₂•⁻ and •OH radicals as dominant species, validating the role of morphology and interface engineering in directing charge separation and redox activity. Additionally, a catalyst performance index was proposed to facilitate comparison across diverse conditions. Overall, this work introduces a novel, durable photocatalyst that links structural design to functional performance and demonstrates strong potential for practical environmental remediation. KW - Heterojunction photocatalyst KW - Photodegradation KW - Tetracycline PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655946 DO - https://doi.org/10.1007/s42114-025-01600-x SN - 2522-0128 VL - 9 IS - 2 SP - 1 EP - 19 PB - Springer Nature CY - London AN - OPUS4-65594 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -