TY - JOUR A1 - Thinnes, A. A1 - Westenberger, M. A1 - Piechotta, Christian A1 - Letho, L. A1 - Wirth, F. A1 - Lau, H. A1 - Klein, J. T1 - Cholinergic and metabolic effects of metformin in mouse brain N2 - Metformin is widely used as a first-line treatment for type 2 diabetes, but central effects of metformin have received little attention. When metformin (200 mg/kg i.p.) was administered to C57Bl6 mice, metformin concentration in cerebrospinal fluid peaked at 29 μM after 30 min but dropped quickly and was low at 90 min. In mouse hypothalamus sampled by microdialysis, systemically administered metformin caused minor and transient increases of acetylcholine, glucose and lactate while choline levels decreased. When metformin (0.2−10 mM) was locally infused via retrodialysis, there was a short-lasting increase of acetylcholine in the hypothalamus. Extracellular lactate levels in hypothalamus showed a massive increase upon metformin infusion while glucose levels decreased. In isolated mitochondria of mouse brain, metformin inhibited oxygen consumption and the activity of complex I. Inhibition of mitochondrial respiration likely explains lactate formation in the brain during metformin infusion which may cause lactic acidosis during metformin intoxication. The changes of cholinergic activity in the hypothalamus may be associated with appetite suppression observed during metformin treatment. KW - Metformin KW - Blood-brain barrier KW - Lactate KW - Glucose KW - Microdialysis KW - Hypothalamus PY - 2021 DO - https://doi.org/10.1016/j.brainresbull.2021.02.018 SN - 0361-9230 VL - 170 SP - 211 EP - 217 PB - Elsevier CY - Amsterdam, Niederlande AN - OPUS4-52189 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rurack, Knut T1 - Chips or strips – the importance of embedding and integration in (bio)chemical assay development N2 - The most important aspect of developing a miniaturized or compact (bio)chemical assay for use outside a dedicated laboratory environment is, of course, the design of the recognition and signaling element that best achieves the required selectivity and sensitivity in relation to the target analyte and analytical scenario. For luminescence assays, this essentially means that the appropriate combination of small-molecule binding units, ligands or biomacromolecular binders such as antibodies or aptamers and organic, metal-organic or rare earth metal ion luminophores or luminescent nanoparticles such as semiconductor nanocrystals, carbon nanodots, polymer dots or fluorescently doped silica or polymer nanoparticles as well as the best strategy for combining binding and signaling unit must be selected. Having accomplished this task and obtained first promising results in a conventional laboratory setting with the use of pipettes, cuvettes and benchtop spectrometers, the challenge is to bridge the gap between such a model assay and an assay that uses a mobile and robust device in the hands of a layperson and does not require complicated operation and extensive manual steps, especially when handling liquids, at best in line with the ASSURED principle, being affordable, sensitive, specific, user-friendly, rapid and robust, equipment free and deliverable to end-users, or, as recently proposed, the REASSURED principle, which furthermore includes real-time connectivity and ease of specimen collection (translating into ease of sampling in the non-diagnostic world). In order to close this gap, it is of utmost importance to know the further requirements of the assay, i.e., whether only one or more than one analyte needs to be detected, what the main potential interferents are and how tolerant the assay is to the sample matrix, as well as how many assays are typically performed per hour/day/week, how long a run should take and how expensive a single analysis should be. These parameters usually determine the most appropriate format, i.e., whether it is a dip stick, a test strip, a lateral flow assay, a microfluidic chip, a 3D-microfluidic approach or a combination thereof, in conjunction with a dedicated readout system or a mobile communication device. This choice in turn determines the most appropriate strategy for integration, i.e., whether the recognition and signaling element are used directly in liquid solution,8 embedded in polymer layers or gels, attached to surfaces of planar substrates, micro- or nanoparticles or immobilized or loaded in micro- or nanoparticles, which could then enable direct or controlled/gated access. This contribution discusses various aspects of this multi-stage process using examples from the group. T2 - How to develop a sensor? Academic Approaches vs. Industrial Interests (EU Training School) CY - Kaiserslautern, Germany DA - 18.09.2024 KW - Sensing KW - Rapid testing KW - Microfluidics KW - Test strips KW - Device integration PY - 2024 AN - OPUS4-61429 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 - CONF A1 - You, Zengchao T1 - Chemometrical analysis of spectral data obtained from glow discharge optical emission spectroscopy for elemental analysis of metals N2 - The poster shows the combination of GD-OES and machine learning. The gola of this project is to establish a new and robust calibration model, which can be used to identify elemental composition and concentration of metals from a single spectra. T2 - Salsa make and measure Konferenz CY - Online meeting DA - 16.09.2021 KW - Glow discharge optical emission spectroscopy KW - Machine learning PY - 2021 AN - OPUS4-53323 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 - Ziegler, K. A1 - Kunert, A. T. A1 - Reinmuth-Selzle, K. A1 - Leifke, A. L. A1 - Widera, D. A1 - Weller, Michael G. A1 - Schuppan, D. A1 - Fröhlich-Nowoisky, J. A1 - Lucas, K. A1 - Pöschl, U. T1 - Chemical modification of pro-inflammatory proteins by peroxynitrite increases activation of TLR4 and NF-κB: Implications for the health effects of air pollution and oxidative stress N2 - Environmental pollutants like fine particulate matter can cause adverse health effects through oxidative stress and inflammation. Reactive oxygen and nitrogen species (ROS/RNS) such as peroxynitrite can chemically modify proteins, but the effects of such modifications on the immune system and human health are not well understood. In the course of inflammatory processes, the Toll-like receptor 4 (TLR4) can sense damage-associated molecular patterns (DAMPs). Here, we investigate how the TLR4 response and pro-inflammatory potential of the proteinous DAMPs α-Synuclein (α-Syn), heat shock protein 60 (HSP60), and high-mobility-group box 1 protein (HMGB1), which are relevant in neurodegenerative and cardiovascular diseases, changes upon chemical modification with peroxynitrite. For the peroxynitrite-modified proteins, we found a strongly enhanced activation of TLR4 and the pro-inflammatory transcription factor NF-κB in stable reporter cell lines as well as increased mRNA expression and secretion of the pro-inflammatory cytokines TNF-α, IL-1β, and IL-8 in human monocytes (THP-1). This enhanced activation of innate immunity via TLR4 is mediated by covalent chemical modifications of the studied DAMPs. Our results show that proteinous DAMPs modified by peroxynitrite more potently amplify inflammation via TLR4 activation than the native DAMPs, and provide first evidence that such modifications can directly enhance innate immune responses via a defined receptor. These findings suggest that environmental pollutants and related ROS/RNS may play a role in promoting acute and chronic inflammatory disorders by structurally modifying the body's own DAMPs. This may have important consequences for chronic neurodegenerative, cardiovascular or gastrointestinal diseases that are prevalent in modern societies, and calls for action, to improve air quality and climate in the Anthropocene. KW - Protein nitration KW - Protein oligomerization KW - Damage-associated molecular patterns (DAMPs) KW - Pattern recognition receptor KW - Anthropocene KW - Environmental pollutants PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517128 DO - https://doi.org/10.1016/j.redox.2020.101581 VL - 37 SP - 101581 PB - Elsevier B.V. AN - OPUS4-51712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Winckelmann, Alexander T1 - Chemical characterization of aging processes in high energy-density lithium-ion batteries N2 - Introduction Lithium-ion batteries (LIBs) are one key technology to overcome the climate crisis and energy transition challenges. Demands of electric vehicles on higher capacity and power drives research on innovative cathode and anode materials. These high energy-density LIBs are operated at higher voltages, leading to increased electrolyte decay and the current collectors' degradation. Even though this fundamental corrosion process significantly affects battery performance, insufficient research is being done on the aluminum current collector. Fast and convenient analytical methods are needed for monitoring the aging processes in LIBs. Methods In this work glow-discharge optical emission spectrometry (GD-OES) was used for depth profile analysis of aged cathode material. The measurements were performed in pulsed radio frequency mode. Under soft and controlled plasma conditions, high-resolution local determination (in depth) of the elemental composition is possible. Scanning electron microscopy (SEM) combined with a focused ion beam (FIB) cutting and energy dispersive X-ray spectroscopy (EDX) was used to confirm GD-OES results and obtain additional information on elemental distribution. Results The aging of coin cells manufactured with different cathode materials (LCO, LMO, NMC111, NMC424, NMC532, NMC622, and NMC811) was studied. GD-OES depth profiling of new and aged cathode materials was performed. Quantitative analysis was possible through calibration with synthetic standards and correction by sputter rate. Different amounts of aluminum deposit on the cathode surface were found for different materials. The deposit has its origin in the corrosion of the aluminum current collector. The results are compatible with results from FIB-EDX. However, GD-OES is a faster and less laborious analytical method. Therefore, it will accelerate research on corrosion processes in high energy-density batteries. Innovative aspects - Quantitative depth profiling of cathode material -Monitoring of corrosion processes in high energy-density lithium-ion batteries - Systematic investigation of the influence of different cathode materials T2 - ANAKON 2023 CY - Vienna, Austria DA - 11.04.2023 KW - Lithium Ion Batteries KW - GD-OES KW - Depth-profiling PY - 2023 AN - OPUS4-58586 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Avci, Fatma T1 - Characterization of black mass by X-Ray fluorescence spectroscopy N2 - X-ray fluorescence analysis (XRF) is a method of elemental analysis that is used either as wavelength dispersive XRF (WDXRF) or energy dispersive XRF (EDXRF). Using EDXRF, it is possible to analyze samples within a few minutes without time-consuming sample preparation. This makes the method potentially suitable for analyzing larger sample quantities under industrial conditions. However, the XRF method is matrix-dependent. Depending on the cathode material of the recycled batteries, there are significant differences in the composition of the resulting black mass. This means that specific calibration models must be developed for different types of black mass. The aim of our work is to use the EDXRF method to reliably analyze black mass of different origins with regard to the elements that are particularly interesting for recycling: nickel (Ni), manganese (Mn), cobalt (Co), aluminum (Al), iron (Fe), zinc (Zn), silicon (Si), copper (Cu), and phosphorus (P). Based on the different mass fractions of the elements mentioned, black masses from used lithium-ion batteries can be divided into three groups according to the cathode chemistry: lithium nickel manganese cobalt oxide (NMC), lithium cobalt oxide (LCO), and mixed chemistries (MC), the latter of which may contain lithium iron phosphate (LFP). The division into groups is necessary to determine the matrices and thus select the appropriate calibration model for the analysis of the EDXRF data in order to achieve the most accurate determination of the elemental content possible. Reference analyses are performed using WDXRF. The score plots obtained by PLS-DA of the specific elemental composition of the black masses examined to date by both WDXRF and EDXRF reveal a correct separation of the BM matrix types LCO, NMC, and MC. Our preliminary results with test samples yielded 100 % correct predictions with both data sets. However, only two matrix types, NMC and LCO, have been tested with the EDXRF data so far. Data for MC is pending as work progresses. T2 - Doctoral seminar 2025 - Working Group Chemometrics and Quality Assurance (GDCh) CY - Hamburg, Germany DA - 11.09.2025 KW - Black Mass KW - XRF Spectroscopy KW - Chemometric Modeling KW - PLS-DA PY - 2025 AN - OPUS4-64095 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chan, George C.-Y. A1 - Engelhard, Carsten A1 - Wiley, Joshua S. A1 - Shoulds, Ayanna U. A1 - Cooks, R. Graham A1 - Hieftje, Gary M. A1 - Shelley, Jacob T. T1 - Characterization of a Low-Temperature Plasma (LTP) Ambient Ionization Source Using Temporally Resolved Monochromatic Imaging Spectrometry N2 - The low-temperature plasma (LTP) probe is a common plasma-based source used for ambient desorption–ionization mass spectrometry (MS). While the LTP probe has been characterized in detail with MS, relatively few studies have used optical spectroscopy. In this paper, two-dimensional (2D) imaging at selected wavelengths is used to visualize important species in the LTP plasma jet. First, 2D steady-state images of the LTP plume for N2+ (391.2 nm), He I (706.5 nm), and N2 (337.1 nm) emissions were recorded under selected plasma conditions. Second, time-resolved 2D emission maps of radiative species in the LTP plasma jet were recorded through the use of a 200 ns detection gate and varying gate delays with respect to the LTP trigger pulse. Emission from He I, N2+, and N2 in the plasma jet region was found to show a transient behavior (often referred to as plasma bullets) lasting only a few microseconds. The N2+ and He I maps were highly correlated in spatial and temporal structure. Further, emission from N2 showed two maxima in time, one before and one after the maximum emission for N2+ and He I, due to an initial electronic excitation wave and ion–electron recombination, respectively. Third, the interaction of the LTP probe with a sample substrate and an electrically grounded metallic needle was studied. Emission from a fluorophore on the sample substrate showed an initial photon-induced excitation from plasma-generated photons followed by electronic excitation by other plasma species. The presence of a grounded needle near the plasma jet significantly extended the plasma jet lifetime and also generated a long-lived corona discharge on the needle. The effect of LTP operating parameters on emission spectra was correlated with mass-spectral results including reagent-ion signals. Lastly, five movies provide a side-by-side comparison of the temporal behavior of emitting species and insights into the interactions of the emission clouds with a sample surface as well as an external needle. Temporally and spatially resolved imaging provided insights into important processes in the LTP plasma jet, which will help improve analyte ion sampling in LTP–MS. KW - Optical spectroscopy KW - Low-temperature plasma KW - Ambient ionization KW - Instrumentation PY - 2023 DO - https://doi.org/10.1177/00037028231184501 VL - 77 IS - 8 SP - 940 EP - 956 PB - SAGE Publications AN - OPUS4-61269 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Characterization and quantification of functional groups and coatings on nanoobjects an overview N2 - Characterization of Nanoparticles – Questions to Ask, Functional Nanoparticles (NPs) – Organic, Inorganic, and Hybrid Nanoparticles Nanomaterial Characterization Standardization – Addressing Remaining Gaps Surface FGs Particle Surface Chemistry - Why is it Important? Particle Surface Chemistry - A Key Driver for Performance, Applications, and Safety Aspects Method Development for Quantifying FGs and Ligands on Particle Surfaces FG Quantification – Method Choice & Criteria Relevant for Data Interpretation Quantifying the Amount of Total and Accessible FGs on Aminated Silica Nanoparticles (SiO2-NH2) Comparing the Total and Accessible –NH2 Content on Aminated Silica NPs of Different Size Characterization of Nanoparticles Standardization Standardized Measurements of Surface FGs on Nanoparticles EMP Project SMURFnano EMP Project SMURFnano Work Packages & Goals Certified Reference Materials from BAM T2 - e-MRS 2024 (Spring Meeting of the European Materials Research Society, Altech Symposium) CY - Strasbourg, France DA - 27.05.2024 KW - Luminescence KW - Nano KW - Particle KW - Quantum yield KW - Quality assurance KW - Interlaboratory comparison KW - Method KW - Uncertainty KW - Reference material KW - Surface analysis KW - Optical assay KW - NMR KW - Silica KW - Ligand PY - 2024 AN - OPUS4-60495 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kazlagić, Anera A1 - Rosner, M. A1 - Cipriani, A. A1 - Frick, D. A. A1 - Glodny, J. A1 - Hoffmann, E. J. A1 - Hora, J. M. A1 - Irrgeher, J. A1 - Lugli, F. A1 - Magna, T. A1 - Meisel, T. C. A1 - Meixner, A. A1 - Possolo, A. A1 - Pramann, A. A1 - Pribil, M. J. A1 - Prohaska, T. A1 - Retzmann, Anika A1 - Rienitz, O. A1 - Rutherford, D. A1 - Paula-Santos, G. M. A1 - Tatzel, M. A1 - Widhalm, S. A1 - Willbold, M. A1 - Zuliani, T. A1 - Vogl, Jochen T1 - Characterisation of conventional 87Sr/86Sr isotope ratios in cement, limestone and slate reference materials based on an interlaboratory comparison study N2 - An interlaboratory comparison (ILC)was organised to characterise 87Sr/86Sr isotope ratios in geological and industrial reference materials by applying the so-called conventional method for determining 87Sr/86Sr isotope ratios. Four cements (VDZ 100a,VDZ 200a, VDZ 300a, IAG OPC-1), one limestone (IAG CGL ML-3) and one slate (IAG OU-6) reference materials were selected, covering a wide range of naturally occurring Sr isotopic signatures. Thirteen laboratories received aliquots of these six reference materials together with a detailed technical protocol. The consensus values for the six reference materials and their associated measurement uncertainties were obtained by applying a Gaussian, linear mixed effects model fitted to all the measurement results. By combining the consensus values and their uncertainties with an uncertainty contribution for potential heterogeneity, reference values ranging from 0.708134 mol mol-1 to 0.729778 mol mol-1 were obtained with relative expanded uncertainties of ≤ 0.007 %. This study represents an ILC on conventional 87Sr/86Sr isotope ratios, within which metrological principles were considered and the compatibility of measurement results obtained by MC-ICP-MS and by MC-TIMS is demonstrated. The materials characterised in this study can be used as reference materials for validation and quality control purposes and to estimate measurement uncertainties in conventional 87Sr/86Sr isotope ratio measurement. KW - Sr isotope analysis KW - Isotope ratios KW - Cement KW - Geological material KW - MC-TIMS KW - MC-ICP-MS KW - Interlaboratory comparison KW - Measurement uncertainty KW - Cconventional method PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579836 DO - https://doi.org/10.1111/ggr.12517 SN - 1639-4488 VL - 47 IS - 4 SP - 821 EP - 840 PB - Wiley online library AN - OPUS4-57983 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Epping, Ruben A1 - Lisec, Jan A1 - Koch, Matthias T1 - Changes in Black Truffle (Tuber melanosporum) Aroma during Storage under Different Conditions N2 - The enticing aroma of truffles is a key factor for their culinary value. Although all truffle species tend to be pricy, the most intensely aromatic species are the most sought after. Research into the aroma of truffles encompasses various disciplines including chemistry, biology, and sensory science. This study focusses on the chemical composition of the aroma of black truffles (Tuber melanosporum) and the changes occurring under different storage conditions. For this, truffle samples were stored under different treatments, at different temperatures, and measured over a total storage time of 12 days. Measurements of the truffle aroma profiles were taken with SPME/GC–MS at regular intervals. To handle the ample data collected, a systematic approach utilizing multivariate data analysis techniques was taken. This approach led to a vast amount of data which we made publicly available for future exploration. Results reveal the complexity of aroma changes, with 695 compounds identified, highlighting the need for a comprehensive understanding. Principal component analyses offer initial insights into truffle composition, while individual compounds may serve as markers for age (formic acid, 1-methylpropyl ester), freshness (2-Methyl-1-propanal; 1-(methylthio)-propane), freezing (tetrahydrofuran), salt treatment (1-chloropentane), or heat exposure (4-hydroxy-3-methyl-2-butanone). This research suggests that heat treatment or salt contact significantly affects truffle aroma, while freezing and cutting have less pronounced effects in comparison. The enrichment of compounds showing significant changes during storage was investigated with a metabolomic pathway analysis. The involvement of some of the enriched compounds on the pyruvate/glycolysis and sulfur pathways was shown. KW - Mass Spectrometry KW - Metabolomics KW - Tuber melanosporum KW - Truffle Aroma PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601731 DO - https://doi.org/10.3390/jof10050354 VL - 10 IS - 5 SP - 1 EP - 22 PB - MDPI AN - OPUS4-60173 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klein, Luise A1 - Wilke, Olaf T1 - Chamber comparison for the determination of initial VOC emissions from consumer products N2 - Volatile organic compound (VOC) emissions from consumer products contribute to human inhalation exposure and may cause adverse health effects. Existing methods to determine long-term VOC emissions from e.g. building products need to be verified for their suitability to reliably detect initial VOC emissions from consumer products within the first hours and days of use, which would facilitate realistic inhalation exposure assessments. To investigate this issue, VOCs emitted from a test sample were determined in a large-scale emission test chamber and in two micro-chambers of different volumes, and the results were compared. T2 - Healthy Buildings 2023 Europe CY - Aachen, Germany DA - 11.06.2023 KW - Micro-chamber KW - Emission test chamber KW - Volatile organic compounds KW - Inhalation exposure KW - Consumer products PY - 2023 SP - 6 EP - 8 AN - OPUS4-58055 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weller, Michael G. T1 - Challenges of protein analysis N2 - Selected Projects BAM Division 1.5 Test for sensitive SARS-CoV-2 detection Corundum as a novel affinity support Troponin biosensor based on chemiluminescence Plant virus purification (CCMV) Protein Quantification by 1H-NMR Ultra-miniaturized Biosensors N2 - Ausgewählte Projekte BAM-Abteilung 1.5 Test für empfindlichen SARS-CoV-2-Nachweis Korund als neuartige Affinitätscarriermaterialien Troponin-Biosensor auf Basis von Chemilumineszenz Reinigung von Pflanzenviren (CCMV) Proteinquantifizierung durch 1H-NMR Ultra-miniaturisierte Biosensoren T2 - Klausurtagung der MPI Abteilung „Multiphasenchemie“ CY - Mainz, Germany DA - 19.11.2024 KW - Corona test KW - Corundum KW - Affinity separation KW - Affinity chromatography KW - Troponin biosensor KW - Peptide aptamer KW - Cowpea chlorotic mottle virus KW - Nanoparticle KW - Nanocarrier KW - Nuclear magnetic resonance NMR KW - Protein quantification KW - HyPhox KW - Ring resonator PY - 2024 AN - OPUS4-62126 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Döring, Sarah A1 - Konthur, Zoltán A1 - Weller, Michael G. A1 - Jaeger, Carsten A1 - Reinders, Yvonne T1 - Challenges and Insights in Absolute Quantification of Recombinant Therapeutic Antibodies by Mass Spectrometry: An Introductory Review N2 - This review describes mass spectrometry (MS)-based approaches for the absolute quantification of therapeutic monoclonal antibodies (mAbs), focusing on technical challenges in sample treatment and calibration. Therapeutic mAbs are crucial for treating cancer and inflammatory, infectious, and autoimmune diseases. We trace their development from hybridoma technology and the first murine mAbs in 1975 to today’s chimeric and fully human mAbs. With increasing commercial relevance, the absolute quantification of mAbs, traceable to an international standard system of units (SI units), has attracted attention from science, industry, and national metrology institutes (NMIs). Quantification of proteotypic peptides after enzymatic digestion using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) has emerged as the most viable strategy, though methods targeting intact mAbs are still being explored. We review peptide-based quantification, focusing on critical experimental steps like denaturation, reduction, alkylation, choice of digestion enzyme, and selection of signature peptides. Challenges in amino acid analysis (AAA) for quantifying pure mAbs and peptide calibrators, along with software tools for targeted MS data analysis, are also discussed. Short explanations within each chapter provide newcomers with an overview of the field’s challenges. We conclude that, despite recent progress, further efforts are needed to overcome the many technical hurdles along the quantification workflow and discuss the prospects of developing standardized protocols and certified reference materials (CRMs) for this goal. We also suggest future applications of newer technologies for absolute mAb quantification. KW - Monoclonal antibody KW - Therapeutic antibodies KW - Mass spectrometry KW - Liquid chromatography KW - Absolute quantification KW - Metrology KW - Traceability KW - Certified reference material PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623707 DO - https://doi.org/10.3390/antib14010003 SN - 2073-4468 VL - 14 IS - 1 SP - 1 EP - 26 PB - MDPI CY - Basel, Schweiz AN - OPUS4-62370 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Döring, Sarah A1 - Weller, Michael G. A1 - Reinders, Yvonne A1 - Konthur, Zoltán A1 - Jaeger, Carsten T1 - Challenges and Insights in Absolute Quantification of Recombinant Therapeutic Antibodies by Mass Spectrometry: An Introductory Review N2 - This review describes mass spectrometry (MS)-based approaches for the absolute quantification of therapeutic monoclonal antibodies (mAbs), focusing on technical challenges in sample treatment and calibration. Therapeutic mAbs are crucial for treating cancer, inflammatory, infectious, and autoimmune diseases. We trace their development from hybridoma technology and the first murine mAbs in 1975 to today’s chimeric and fully human mAbs. With increasing commercial relevance, absolute quantification of mAbs, traceable to SI units, has attracted attention from science, industry, and national metrology institutes (NMIs). Quantification of proteotypic peptides after enzymatic digestion using liquid chromatography-tandem mass spectrometry (LC-MS/MS) has emerged as the most viable strategy, though methods targeting intact mAbs are still being explored. We review peptide-based quantification, focusing on critical experimental steps like denaturation, reduction, alkylation, choice of digestion enzyme, and selection of signature peptides. Challenges in amino acid analysis (AAA) for quantifying pure mAbs and peptide calibrators, along with software tools for targeted MS data analysis, are also discussed. Short explanations within each chapter provide newcomers an overview of the field’s challenges. Finally, we discuss prospects and limitations of developing standardized protocols and certified reference materials (CRMs) and suggest future applications of newer technologies for the absolute quantification of therapeutic antibodies. KW - Antibody KW - Mass spectrometry KW - Absolute quantification KW - Metrology KW - Reference products PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621841 DO - https://doi.org/10.20944/preprints202412.1081.v1 SP - 1 EP - 22 PB - MDPI AN - OPUS4-62184 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Güttler, Arne T1 - Certified Reference Materials for the Quantification and Standardization of Fluorescence-based Measurements N2 - The size and shape of photoluminescence signals is affected by wavelength-, polarization-, and time-dependent instrumentspecific contributions and the compound- and environment-specific photoluminescence quantum yield. The former hamper the comparability of fluorescence measurements performed on different measuring devices. The commonly relatively done determination of the performance parameter requires suitable quantum yield standards with well-known. The performance of such measurements is, e.g., described in the written standard IEC 62607 currently revised. T2 - Colloquium für Optische Spektrometrie 2025 CY - Jena, Germany DA - 24.09.2025 KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Advanced material KW - Calibration KW - Characterization KW - Fluorescence quantum yield KW - Phosphor KW - Absolute KW - Integrating sphere spectroscopy KW - Dye KW - Standardization KW - Reference material KW - Interlaboratory comparison KW - Uncertainty PY - 2025 AN - OPUS4-64213 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Recknagel, Sebastian T1 - Certified reference materials for the determination of cadmium (Cd) in cocoa N2 - BAM has produced three cocoa CRMs certified for cadmium (ERM-BD513 – 515) as tools for checking analytical methods for Cd-determination. KW - Certified reference material KW - Cocoa KW - Cadmium PY - 2021 SP - 4 EP - 4 AN - OPUS4-53694 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Recknagel, Sebastian T1 - Certified reference material for the determination of hydrolytic resistance of borosilicate glass N2 - The preparation, analysis and certification of a new certified glass reference material (CRM) for the determination of hydrolytic resistance of borosilicate glass with the glass grains test is described. The CRM BAM-S053 is available in the form of glass rods (length: 185 mm, diameter: 9 mm, weight: 27·5 g). Certified properties are the acid consumption determined according to the procedures described in ISO 720, USP<660>, Ph.Eur. 3.2.1, data obtained following the procedure of ISO 719 was scattering too widely. The certified values are based on the results of 15 laboratories which participated in the certification interlaboratory comparison. The CRM is intended for the quality control when applying ISO 720, USP<660>, Ph.Eur. 3.2.1 and with limitations ISO 719. KW - CRM KW - Hydrolytic resistance KW - Borosilicate glass PY - 2021 DO - https://doi.org/10.13036/17533562.62.1.001 VL - 62 IS - 1 SP - 25 EP - 27 AN - OPUS4-52195 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Recknagel, Sebastian T1 - Certified reference material for the determination of hydrolytic resistance of borosilicate glass N2 - The preparation of certified reference material for the determination of hydrolytic resistance of borosilicate glass is described. Certified properties are the acid consumption according to the relevant standard procedures described in ISO 720, USP<660> and Ph.Eur. 3.2.1. T2 - 26. International Congress on Glass CY - Berlin, Germany DA - 03.07.2022 KW - Borosilicate glass KW - CRM KW - Hydrolytic resistance PY - 2022 AN - OPUS4-55521 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -