TY - JOUR A1 - Lemke, Nora A1 - El-Khatib, Ahmed H. A1 - Tchipilov, Teodor A1 - Jakubowski, N. A1 - Weller, Michael G. A1 - Vogl, Jochen T1 - Procedure providing SI‑traceable results for the calibration of protein standards by sulfur determination and its application on tau N2 - Quantitative proteomics is a growing research area and one of the most important tools in the life sciences. Well-characterized and quantified protein standards are needed to achieve accurate and reliable results. However, only a limited number of sufficiently characterized protein standards are currently available. To fill this gap, a method for traceable protein quantification using sulfur isotope dilution inductively coupled plasma mass spectrometry (ICP-MS) was developed in this study. Gel filtration and membrane filtration were tested for the separation of non-protein-bound sulfur in the protein solution. Membrane filtration demonstrated a better performance due to the lower workload and the very low sulfur blanks of 11 ng, making it well suited for high-purity proteins such as NIST SRM 927, a bovine serum albumin (BSA). The method development was accomplished with NIST SRM 927e and a commercial avidin. The quantified mass fraction of NIST SRM 927e agreed very well with the certified value and showed similar uncertainties (3.6%) as established methods while requiring less sample preparation and no species-specific standards. Finally, the developed procedure was applied to the tau protein, which is a biomarker for a group of neurodegenerative diseases denoted “tauopathies” including, e.g., Alzheimer’s disease and frontotemporal dementia. For the absolute quantification of tau in the brain of transgenic mice overexpressing human tau, a well-defined calibration standard was needed. Therefore, a pure tau solution was quantified, yielding a protein mass fraction of (0.328 ± 0.036) g/kg, which was confirmed by amino acid analysis. KW - Iinductively coupled plasma mass spectrometry KW - Isotope dilution KW - Quantitative protein analysis KW - Sulfur KW - SI traceability PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545200 DO - https://doi.org/10.1007/s00216-022-03974-z VL - 414 SP - 4441 EP - 4455 PB - Springer Verlag AN - OPUS4-54520 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mi, W. A1 - Josephs, R. D. A1 - Melanson, J. E. A1 - Dai, X. A1 - Wang, Y. A1 - Zhai, R. A1 - Chu, Z. A1 - Fang, X. A1 - Thibeault, M.-P. A1 - Stocks, B. B. A1 - Meija, J. A1 - Bedu, M. A1 - Martos, G. A1 - Westwood, S. A1 - Wielgosz, R. I. A1 - Liu, Q. A1 - Teo, T. L. A1 - Liu, H. A1 - Tan, Y. J. A1 - Öztuğ, M. A1 - Saban, E. A1 - Kinumi, T. A1 - Saikusa, K. A1 - Schneider, Rudolf A1 - Weller, Michael G. A1 - Konthur, Zoltán A1 - Jaeger, Carsten A1 - Quaglia, M. A1 - Mussell, C. A1 - Drinkwater, G. A1 - Giangrande, C. A1 - Vaneeckhoutte, H. A1 - Boeuf, A. A1 - Delatour, V. A1 - Lee, J. E. A1 - O'Connor, G. A1 - Ohlendorf, R. A1 - Henrion, A. A1 - Beltrão, P. J. A1 - Naressi Scapin, S. M. A1 - Sade, Y. B. T1 - PAWG Pilot Study on Quantification of SARS-CoV-2 Monoclonal Antibody - Part 1 N2 - Under the auspices of the Protein Analysis Working Group (PAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a pilot study, CCQM-P216, was coordinated by the Chinese National Institute of Metrology (NIM), National Research Council of Canada (NRC) and the Bureau International des Poids et Mesures (BIPM). Eleven Metrology Institutes or Designated Institutes and the BIPM participated in the first phase of the pilot study (Part 1). The purpose of this pilot study was to develop measurement capabilities for larger proteins using a recombinant humanized IgG monoclonal antibody against Spike glycoprotein of SARS-CoV-2 (Anti-S IgG mAb) in solution. The first phase of the study was designed to employ established methods that had been previously studies by the CCQM Protein Analysis Working Group, involving the digestion of protein down to the peptide or amino acid level. The global coronavirus pandemic has also led to increased focus on antibody quantitation methods. IgG are among the immunoglobulins produced by the immune system to provide protection against SARS-CoV-2. Anti-SARS-CoV-2 IgG can therefore be detected in samples from affected patients. Antibody tests can show whether a person has been exposed to the SARS-CoV-2, and whether or not they potentially show lasting immunity to the disease. With the constant spread of the virus and the high pressure of re-opening economies, antibody testing plays a critical role in the fight against COVID-19 by helping healthcare professionals to identify individuals who have developed an immune response, either via vaccination or exposure to the virus. Many countries have launched large-scale antibody testing for COVID-19. The development of measurement standards for the antibody detection of SARS-CoV-2 is critically important to deal with the challenges of the COVID-19 pandemic. In this study, the SARS-CoV-2 monoclonal antibody is being used as a model system to build capacity in methods that can be used in antibody quantification. Amino acid reference values with corresponding expanded uncertainty of 36.10 ± 1.55 mg/kg, 38.75 ± 1.45 mg/kg, 18.46 ± 0.78 mg/kg, 16.20 ± 0.67 mg/kg and 30.61 ± 1.30 mg/kg have been established for leucine, valine, phenylalanine, isoleucine and proline, respectively. Agreement between nearly all laboratories was achieved for the amino acid analysis within 2 to 2.5 %, with one participant achieving markedly higher results due to a technical issue found in their procedure; this result was thus excluded from the reference value calculations. The relatively good agreement within a laboratory between different amino acids was not dissimilar to previous results for peptides or small proteins, indicating that factors such as hydrolysis conditions and calibration procedures could be the largest sources of variability. Peptide reference values with corresponding expanded uncertainty of 4.99 ± 0.28 mg/kg and 6.83 ± 0.65 mg/kg have been established for ALPAPIEK and GPSVFPLAPSSK, respectively. Not surprisingly due to prior knowledge from previous studies on peptide quantitation, agreement between laboratories for the peptide-based analysis was slightly poorer at 3 to 5 %, with one laboratory's result excluded for the peptide GPSVFPLAPSSK. Again, this level of agreement was not significantly poorer than that achieved in previous studies with smaller or less complex proteins. To reach the main text of this paper, click on Final Report. KW - Antibody quantification KW - Amino acid analysis KW - Peptide analysis KW - Round robin test PY - 2021 DO - https://doi.org/10.1088/0026-1394/59/1a/08001 VL - 59 IS - 1A SP - 08001 AN - OPUS4-54972 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Hahn, Oliver A1 - Steimer, Hans Gerhard ED - Christen, Felix ED - Vöhler, Martin T1 - Hölderlins Tinten. Röntgenfluoreszenzanalyse an Handschriften des Spätwerks N2 - Erstmalig in der Hölderlin-Forschung wurde mit dem Projekt der geisteswissenschaftlichen Methodik – über die Beachtung der Wasserzeichen hinaus – ein materialwissenschaftlicher Ansatz zur Seite gestellt, um Arbeitsphasen im Werk Friedrich Hölderlins sichtbar zu machen. Wesentlich ist dabei die Verzahnung von philologischer und naturwissenschaftlicher Perspektive. Wesentlicher Bestandteil der Messungen bildet das sogenannte Homburger Folioheft. Weiterhin wurden Briefe und Manuskripte aus den Beständen der Württembergische Landesbibliothek sowie zwei eigenhändige Gehaltsquittungen aus dem Hessischen Hauptstaatsarchiv Wiesbaden untersucht. Zwei in mehreren Manuskripten klar unterscheidbare Tinten lassen sich mit einiger Wahrscheinlichkeit biografisch mit dem Zeitraum zwischen Hölderlins Rückkehr aus der Schweiz im April 1801 und seinem Weggang nach Frankreich im Dezember dieses Jahres in Verbindung bringen. Für den in den untersuchten Handschriften häufigsten Tintentyp liegen datierbare Belege zwischen Januar 1803 und März 1804 vor, anzunehmen ist seine Verwendung zwischen Oktober 1802 und Juni 1804. Er dominiert auch im Homburger Folioheft. Eine vierte mehrfach vertretene Tinte gebraucht Hölderlin nach seiner Übersiedlung von Nürtingen nach Homburg. Sie findet sich im Folioheft und in einigen Einzelhandschriften. Damit können die in der Forschung umstrittenen Fragen geklärt werden, a) ob dem Dichter das Homburger Folioheft bei seinem zweiten Aufenthalt in Homburg zur Verfügung stand und b) ob überhaupt Werkhandschriften aus dieser Zeit erhalten sind. Darüber hinaus lässt sich über die Röntgenfluoreszenzanalyse der Arbeitsstand in den untersuchten Manuskripten zum Zeitpunkt des Ortswechsels im Juni 1804 genau angeben. Auch Einzelbefunde singulärer oder in nur wenigen Stücken belegter Tinten geben gelegentlich Anhaltspunkte zur Datierung. KW - Manuskript KW - Röntgenfluoreszenzanalyse KW - Eisengallustinte PY - 2026 SN - 978-3-7705-7073-7 SN - 0340-6849 VL - 44 SP - 287 EP - 335 PB - Brill CY - Paderborn AN - OPUS4-65600 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Steglich, Patrick T1 - Towards monolithic integration of polymer-based electro-optical devices in silicon photonic integrated circuits using a 250 nm SOI technology N2 - Silicon-based photonic integrated circuits (PICs) in complementary metal oxide semiconductor (CMOS) technology are essential for next-generation communication systems and neuromorphic computing. However, silicon does not have efficient electro-optical (EO) effects. Since silicon limits the performance of current photonic devices, more advanced materials such as nonlinear optical polymers are needed to exploit the full potential of PICs. As a preliminary proof of concept, we demonstrate the quadratic EO effect and the electric field-induced EO effect using a Mach-Zehnder interferometer in conjunction with a co-integrated Ge photodiode. Our concept of monolithic integration could pave the way for next-generation PICs. T2 - SPIE Optics + Optoelectronics 2025 CY - Prague, Czech Republic DA - 05.06.2025 KW - CMOS KW - Silicon-based photonic integrated circuits KW - Mach-Zehnder interferometer KW - Ge-photodiode PY - 2025 UR - https://www.spiedigitallibrary.org/conference-proceedings-of-spie/13530/135300R/Towards-monolithic-integration-of-polymer-based-electro-optical-devices-in/10.1117/12.3056280.short DO - https://doi.org/10.1117/12.3056280 AN - OPUS4-63569 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Bosc-Bierne, Gaby A1 - Ewald, Shireen A1 - Kreuzer, Oliver J. A1 - Weller, Michael G. T1 - Efficient Quality Control of Peptide Pools N2 - Peptide pools composed of short amino acid sequences have proven to be versatile tools in various research areas and clinical applications. They are powerful tools for epitope mapping, immunotherapy, and vaccine development. Their importance lies in their ability to map complex protein structures, enabling a comprehensive understanding of immune responses and facilitating the identification of potential therapeutic agents. The application of peptide pools also extends to the field of personalized medicine, offering tailored solutions for diseases such as cancer and infectious diseases. Peptide pools are complex mixtures of immunostimulatory antigens primarily intended for T-cell stimulation. They are commercially available in many different compositions and variants. However, unlike other reagents that consist of only one or a few compounds, peptide pools are highly complex products with limited stability. This makes their quality control a major challenge. Quantitative peptide analysis usually requires sophisticated methods, in most cases isotope-labeled standards and reference materials. None of these are routinely available for these products. Synthesis and purification of all labeled peptides might be required. Usually, this approach would be prohibitively laborious and expensive. Therefore, an approach is needed to provide a practical and feasible method for quality control of peptide pools. With insufficient quality control, the use of such products could lead to incorrect experimental results, which would worsen the well-known reproducibility crisis in the biomedical sciences. Here we propose the use of ultra-high performance liquid chromatography (UHPLC) with two detectors, a standard UV detector (at 214 nm) for quantitative analysis and a high-resolution mass spectrometer (HRMS) for identity confirmation. To be cost-efficient and fast, quantification and identification are performed in one chromatographic run. An optimized protocol is shown, and different peak integration methods are compared and discussed. This work was performed using a peptide pool known as CEF, which consists of 32 peptides derived from cytomegalovirus (CMV), Epstein-Barr virus (EBV) and influenza virus, ranging from 8 to 12 amino acids in length. N2 - Peptidpools, die aus kurzen Aminosäuresequenzen bestehen, haben sich in verschiedenen Forschungsbereichen und klinischen Anwendungen als vielseitige Werkzeuge erwiesen. Sie sind leistungsstarke Werkzeuge für die Epitopkartierung, die Immuntherapie und die Impfstoffentwicklung. Ihre Bedeutung liegt in ihrer Fähigkeit, komplexe Proteinstrukturen zu kartieren, was ein umfassendes Verständnis der Immunantworten ermöglicht und die Identifizierung potenzieller Therapeutika erleichtert. Die Anwendung von Peptidpools erstreckt sich auch auf den Bereich der personalisierten Medizin und bietet maßgeschneiderte Lösungen für Krankheiten wie Krebs und Infektionskrankheiten. Peptidpools sind komplexe Mischungen immunstimulierender Antigene, die hauptsächlich zur T-Zell-Stimulation bestimmt sind. Sie sind in vielen verschiedenen Zusammensetzungen und Varianten im Handel erhältlich. Im Gegensatz zu anderen Reagenzien, die nur aus einer oder wenigen Verbindungen bestehen, sind Peptidpools jedoch hochkomplexe Produkte mit begrenzter Stabilität. Dies macht ihre Qualitätskontrolle zu einer großen Herausforderung. Die quantitative Peptidanalyse erfordert in der Regel ausgefeilte Methoden, in den meisten Fällen isotopenmarkierte Standards und Referenzmaterialien. Keines dieser Verfahren ist für diese Produkte routinemäßig verfügbar. Möglicherweise ist die Synthese und Reinigung aller markierten Peptide erforderlich. In der Regel wäre dieser Ansatz unerschwinglich aufwendig und teuer. Daher ist ein Ansatz erforderlich, der eine praktische und praktikable Methode für die Qualitätskontrolle von Peptidpools bietet. Bei unzureichender Qualitätskontrolle könnte die Verwendung solcher Produkte zu falschen Versuchsergebnissen führen, was die bekannte Reproduzierbarkeitskrise in den biomedizinischen Wissenschaften verschlimmern würde. Hier schlagen wir die Verwendung der Ultrahochleistungsflüssigkeitschromatographie (UHPLC) mit zwei Detektoren vor, einem Standard-UV-Detektor (bei 214 nm) für die quantitative Analyse und einem hochauflösenden Massenspektrometer (HRMS) für die Identitätsbestätigung. Um kosteneffizient und schnell zu sein, werden Quantifizierung und Identifizierung in einem chromatographischen Durchlauf durchgeführt. Es wird ein optimiertes Protokoll vorgestellt und verschiedene Peak-Integrationsmethoden werden verglichen und diskutiert. Diese Arbeit wurde mit einem Peptidpool namens CEF durchgeführt, der aus 32 Peptiden besteht, die vom Cytomegalovirus (CMV), Epstein-Barr-Virus (EBV) und Influenzavirus stammen und zwischen 8 und 12 Aminosäuren lang sind. KW - Quality control KW - UHPLC-UV-HRMS KW - Relative peptide quantification KW - Compound confirmation KW - Structure confirmation KW - Cost efficiency KW - Infectious diseases KW - Orbitrap PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621307 DO - https://doi.org/10.20944/preprints202404.0992.v1 SN - 2310-287X SP - 1 EP - 18 PB - MDPI CY - Basel AN - OPUS4-62130 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reinmuth-Selzle, K. A1 - Tchipilov, Teodor A1 - Backes, A. T. A1 - Tscheuschner, Georg A1 - Tang, K. A1 - Ziegler, K. A1 - Lucas, K. A1 - Pöschl, U. A1 - Fröhlich-Nowoisky, J. A1 - Weller, Michael G. T1 - Determination of the protein content of complex samples by aromatic amino acid analysis, liquid chromatography-UV absorbance, and colorimetry N2 - Fast and accurate determination of the protein content of a sample is an important and non-trivial task of many biochemical, biomedical, food chemical, pharmaceutical, and environmental research activities. Different methods of total protein determination are used for a wide range of proteins with highly variable properties in complex matrices. These methods usually work reasonably well for proteins under controlled conditions, but the results for non-standard and complex samples are often questionable. Here, we compare new and well-established methods, including traditional amino acid analysis (AAA), aromatic amino acid analysis (AAAA) based on the amino acids phenylalanine and tyrosine, reversed-phase liquid chromatography of intact proteins with UV absorbance measurements at 220 and 280 nm (LC-220, LC-280), and colorimetric assays like Coomassie Blue G-250 dye-binding assay (Bradford) and bicinchoninic acid (BCA) assay. We investigated different samples, including proteins with challenging properties, chemical modifications, mixtures, and complex matrices like air particulate matter and pollen extracts. All methods yielded accurate and precise results for the protein and matrix used for calibration. AAA, AAAA with fluorescence detection, and the LC-220 method yielded robust results even under more challenging conditions (variable analytes and matrices). These methods turned out to be well-suited for reliable determination of the protein content in a wide range of samples, such as air particulate matter and pollen. KW - Air particulate matter KW - Aromatic amino acid analysis KW - Atmospheric aerosol KW - Chemical protein modification KW - Derivatization KW - Nitration KW - Nitrotyrosine KW - LC-UV absorbance KW - Pollen extract KW - Protein quantification KW - Protein test KW - Kjeldahl KW - Tyrosine KW - Phenylalanine KW - Hydrolysis KW - Bradford KW - BCA test KW - 280 nm KW - Air filter samples KW - Fluorescence KW - HPLC KW - Chromatography KW - Protein content KW - 150th anniversary of BAM KW - Topical collection: Analytical Methods and Applications in the Materials and Life Sciences PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545924 UR - https://pubmed.ncbi.nlm.nih.gov/35320366/ DO - https://doi.org/10.1007/s00216-022-03910-1 SP - 1 EP - 14 PB - Springer Nature Limited CY - New York, Heidelberg AN - OPUS4-54592 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Keller, S. A1 - Borde, T. A1 - Brangsch, J. A1 - Reimann, C. A1 - Kader, A. A1 - Schulze, D. A1 - Buchholz, R. A1 - Kaufmann, Jan Ole A1 - Karst, U. A1 - Schellenberger, E. A1 - Hamm, B. A1 - Makowski, M. R. T1 - Assessment of the hepatic tumor extracellular matrix using elastin‑specific molecular magnetic resonance imaging in an experimental rabbit cancer model N2 - To investigate the imaging performance of an elastin-specific molecular magnetic resonance imaging (MRI) probe with respect to the extracellular matrix (ECM) in an experimental hepatic cancer model. Twelve rabbits with hepatic VX2 tumors were examined using 3 T MRI 14, 21, and 28 days after tumor implantation for two subsequent days (gadobutrol, day 1; elastin-specific probe, day 2). The relative enhancement (RE) of segmented tumor regions (central and margin) and the peritumoral matrix was calculated using pre-contrast and delayed-phase T1w sequences. MRI measurements were correlated to histopathology and element-specific and spatially resolved mass spectrometry (MS). Mixed-model analysis was performed to assess the performance of the elastin-specific probe. In comparison to gadobutrol, the elastin probe showed significantly stronger RE, which was pronounced in the tumor margin (day 14–28: P ≤ 0.007). In addition, the elastin probe was superior in discriminating between tumor regions (χ2(4) = 65.87; P < 0.001). MRI-based measurements of the elastin probe significantly correlated with the ex vivo elastinstain (R = .84; P <0 .001) and absolute gadolinium concentrations (ICP-MS: R = .73, P <0 .01). LA-ICP-MS imaging confirmed the colocalization of the elastin-specific probe with elastic fibers. Elastin-specific molecular MRI is superior to non-specific gadolinium-based contrast agents in imaging the ECM of hepatic tumors and the peritumoral tissue. KW - Elastin-specific molecular agent KW - Extracellular matrix KW - Hepatocellular carcinoma KW - Inductively coupled plasma mass spectroscopy KW - Laser ablation-inductively coupled plasma-mass spectrometry KW - Magnetic resonance imaging KW - MR imaging KW - ESMA KW - Gadolinium PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517360 DO - https://doi.org/10.1038/s41598-020-77624-8 VL - 10 IS - 1 SP - 20785 PB - Nature AN - OPUS4-51736 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 - Altmann, Korinna A1 - Portela, Raquel A1 - Barbero, Francesco A1 - Breuninger, Esther A1 - Camassa, Laura Maria Azzurra A1 - Velickovic, Tanja Cirkovic A1 - Charitidis, Costas A1 - Costa, Anna A1 - Fadda, Marta A1 - Fengler, Petra A1 - Fenoglio, Ivana A1 - Giovannozzi, Andrea M. A1 - Haugen, Øyvind Pernell A1 - Kainourgios, Panagiotis A1 - von der Kammer, Frank A1 - Kirchner, Markus J. A1 - Lomax-Vogt, Madeleine A1 - Lujic, Tamara A1 - Milczewski, Frank A1 - Moussawi, Mhamad Aly A1 - Ortelli, Simona A1 - Parac-Vogt, Tatjana N. A1 - Potthoff, Annegret A1 - Reinosa, Julian J. A1 - Röschter, Sophie A1 - Sacco, Alessio A1 - Wimmer, Lukas A1 - Zanoni, Ilaria A1 - Dailey, Lea Ann T1 - Characterizing nanoplastic suspensions of increasing complexity: Inter-laboratory comparison of size measurements using dynamic light scattering N2 - Understanding the potential human health risks associated with micro- and nanoplastic exposure is currently a priority research area. Nanoplastic toxicity studies are complicated by the lack of available, well-characterized test and reference materials. Further, many nanoplastic test materials are inherently more polydisperse and heterogenous in shape compared to polystyrene beads, making accurate and representative size distribution measurements particularly challenging. The aim of this study was to conduct an inter-laboratory comparison of dynamic light scattering measurements, the most commonly used particle sizing method for nanomaterials. Using a published standard operating procedure, size measurements in water and a standardized cell culture medium (CCM) were generated for spherical, carboxy-functionalized polystyrene nanoparticles (PS-COOH; 50 nm; benchmark material), and for increasingly complex in-house produced spherical poly(ethylene terephthalate) (nanoPET) and irregular shaped polypropylene (nanoPP) test materials. The weighted mean of hydrodynamic diameters of PS-COOH dispersed in water (55 ± 5 nm) showed moderate variation between labs (coefficient of variation, CV = 8.2%) and were similar to literature reports. Measurements of nanoPET (82 ± 6 nm) and nanoPP (182 ± 12 nm) in water exhibited similar CV values (nanoPET: 7.3% and nanoPP; 6.8%). Dispersion of PS-COOH and nanoPET in CCM increased the CV to 15.1 and 14.2%, respectively, which is lower than literature reports (CV = 30%). We conclude with a series of practical recommendations for robust size measurements of nanoplastics in both water and complex media highlighting that strict adherence to a standard operating procedure is required to prevent particle agglomeration in CCM KW - Nanoplastics KW - Reference materials KW - Polypropylene PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644571 DO - https://doi.org/10.1039/d5en00645g SN - 2051-8153 SP - 1 EP - 15 PB - Royal Society of Chemistry (RSC) CY - Cambridge AN - OPUS4-64457 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Alasonati, E A1 - Bartczak, D A1 - Altmann, Korinna A1 - Giovannozzi, A T1 - Towards Standardised Micro and Nanoplastics Analysis via Interlaboratory Comparisons: First Outlook of the VAMAS TWA 45 P3 Project N2 - This talk is part of the stakeholder workshop of the PlasticTrace project held in September 2025 in Oslo. The presentation shows first results of the VAMAS ILC on nanoplastics. PP nanoparticles were given to the participants. These were asked to measure the mass or particle number or size of the PP nanoplastics. Various techniques such as DLS, FFF, Py-GC/MS, TED-GC/MS, PTA were used. T2 - Stakeholder Workshop PlasticsTrace CY - Online meeting DA - 09.09.2025 KW - Nanoplastics KW - ILC KW - DLS KW - Polypropylene PY - 2025 AN - OPUS4-64714 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna T1 - Wessen Problem ist Mikroplastik eigentlich? N2 - In den letzten 20 Jahren ist die Aufmerksamkeit vieler Forschender sowie der Politik und der Bürger selbst auf ein wachsendes Kunststoffproblem unserer Zeit stark gestiegen. Mangelnde Wertstoffkonzepte, Sammelstellen und unbedachtes Einbringen von Kunststoffprodukten in die Umwelt führen dort zu einer Anreicherung. Durch äußere Witterungseinflüsse können diese Produkte degradieren und fraktionieren, so dass heute in allen Teilen der Welt Mikroplastik (1-1000 µm, ISO/TR 21960:2020) unterschiedlicher Polymermaterialien nachgewiesen werden kann. Bei Mikroplastik gilt das Vorsorgeprinzip. Die Partikel können weiter zerfallen in Nanoplastik (< 1 µm, ISO/TR 21960:2020). Ob eine toxikologische Gefährdung von Mikro- oder Nanoplastik ausgeht, wird vielfältig untersucht. Bisher stehen valide Ergebnisse aus. Untersuchungen zur Häufigkeit, dem Transport und möglicher Senken und Eintragspfade muss aber Rechenschafft getragen werden, so dass ein Monitoring von Mikroplastik bereits in der Revision der Trinkwasserrahmen-Richtlinie und der Abwasserrahmen-Richtlinie gefordert wird. Bedenklich ist auch die Verordnung über Mindestanforderungen an die Wasserwiederverwendung (2020/741), in welcher nicht verbindlich gesagt wird, Wasser welcher Reinigungsstufe eines Klärwerks auf die Felder zur Wiederverwendung aufgebracht werden darf. Einer Regulierung über die EU-Plastikstrategie hinaus mit z.B. Verboten für Einwegplastik-Produkte und Rezyklingquoten kann nur entgegengewirkt werden, wenn valide Messmethoden, Referenzmaterialien und Standards existieren, die das tatsächliche Ausmaß von Mikroplastik-Konzentrationen in Luft, Wasser, Boden und Biota zuverlässig und genau aufzeigen. T2 - Technomer CY - Chemnitz, Germany DA - 06.11.2025 KW - Mikroplastik KW - Referenzmaterial KW - TED-GC/MS PY - 2025 AN - OPUS4-64618 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Putzu, Mara A1 - Wiesner, Yosri A1 - Weimann, Christiane A1 - Hodoroaba, Vasile-Dan A1 - Muniategui Lorenzo, Soledad A1 - Fernández-Gonzáles, Verónica A1 - Booth, Andy M. A1 - Igartua, Amaia A1 - Benismail, Nizar A1 - Coïc, Laureen A1 - Chivas-Joly, Carine A1 - Fenoglio, Ivana A1 - Rossi, Andrea Mario A1 - Giovannozzi, Andrea Mario A1 - Altmann, Korinna T1 - Optimization of tablet processing as a reference material for microplastic detection methods N2 - Reference materials (RMs) are essential and highly demanded tools for the development and validation of methods for microplastic (MP) quantification in complex matrices, to ensure comparable and harmonized approaches aligned with EU commission criteria for monitoring MPs (e.g., Drinking Water Directive and Urban Wastewater Treatment Directive). This study investigates different approaches for optimizing the production of polypropylene (PP) RMs in the form of water-soluble tablets, which were carefully evaluated for their homogeneity and stability according to ISO Guide 30, ISO 33401, and ISO 33405. PP particles (1–100 μm) were produced by cryomilling and embedded in a lactose/PEG matrix, then pressed into tablets (18 µg theoretical PP mass). The production process was optimized by varying (i) the size distribution of the matrix components and (ii) the mixer instrument. The materials obtained were characterized by thermogravimetric analysis to assess the homogeneity distribution of MPs with respect to PP mass in the individual tablets and their stability over a 4-month period. The most promising approach, with a homogenous mass of 19 μg (standard deviation of 4 μg), relative standard deviation of 19%, was further investigated for homogeneity by comparison with thermo-analytical mass determination methods, such as TED-GC/MS (thermal extraction desorption-gas chromatography/mass spectrometry) and Py-GC/MS (pyrolysis-gas chromatography-mass spectrometry), and for number-based characterization using micro-Raman spectroscopy. Material characterization was also examined using laser diffraction, scanning electron microscopy, and ATR-FTIR. Based on the results, the optimized processing protocol yields a PP RM suitable for quality control and method performance studies supporting standardization. KW - Microplastics KW - TED-GC/MS KW - Reference materials KW - Polypropylene PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653290 DO - https://doi.org/10.1007/s00216-025-06271-7 SN - 1618-2642 SP - 1 EP - 14 PB - Springer Science and Business Media LLC AN - OPUS4-65329 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Putzu, Mara A1 - Barbaresi, Marta A1 - Fadda, Marta A1 - Sacco, Alessio A1 - Piergiovanni, Maurizio A1 - Masino, Matteo A1 - Bianchi, Federica A1 - Altmann, Korinna A1 - Benismail, Nizar A1 - Coïc, Laureen A1 - Fenoglio, Ivana A1 - Mattarozzi, Monica A1 - Rossi, Andrea Mario A1 - Careri, Maria A1 - Giovannozzi, Andrea Mario T1 - Accuracy assessment of a micro-Raman spectroscopy method for small microplastic particles in infant milk formula N2 - The presence of microplastics (MPs) in the food chain is increasingly documented, raising concerns over potential risks to human health. Despite growing efforts, standardized methods for MPs detection in food matrices remain limited. This study presents an interlaboratory comparison (ILC) aimed at assessing the accuracy and comparability of an analytical approach for the identification and quantification of small MPs (5–100 μm) in infant milk powder using μ-Raman spectroscopy and a representative polyethylene terephthalate (PET) reference material (RM). The RM, formulated as water-soluble tablets, was designed to replicate the morphology, size distribution, and polymer composition of environmentally relevant MPs, and was previously assessed for homogeneity and stability for mass fraction and particle numbers. The approach was assessed using two PET RM batches with different MPs particle numbers (high load batch: 1759 ± 141 MPs; low load batch: 160 ± 22 MPs), subjected to an enzymatic–chemical digestion, followed by μ-Raman analysis performed independently in two laboratories with different instruments and operators. Results are reported as absolute particle counts per analyzed sample and demonstrated excellent recovery across all size classes, including the smallest particles (down to 5 μm), with recovery rates ranging from 82 % to 88 %, in good agreement with the RM reference values. The analytical approach proved to be robust, reproducible, and suitable for low-level MPs quantification in complex food matrices, supporting ongoing efforts toward method harmonization and standardization for reliable MPs monitoring in the food sector. KW - Microplastics KW - Milk KW - Raman microspectroscopy PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-646239 DO - https://doi.org/10.1016/j.talo.2025.100586 SN - 2666-8319 VL - 12 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-64623 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiesner, Yosri A1 - Eisentraut, Paul A1 - Altmann, Korinna T1 - One Year Observation of Microplastic Concentrations in the River Rhine N2 - In recent years, the quantification of microplastics (MP) in aquatic environments has gained increasing attention, particularly regarding their environmental distribution and potential exposure levels. Environmentally relevant exposure data are still essential for a realistic risk assessment of the harmful health potential of microplastics in freshwater systems. This study addresses a large data set of MP concentrations analyzed and processed under statistical aspects and provides mass concentrations as well as associated size fractions of the detected MP. Over a 12 month period, samples were collected at three locations and analyzed across three particle size fractions (100−500 μm, 50−100 μm, and 10−50 μm) using thermalextraction desorption-gas chromatography/mass spectrometry (TED-GC/MS). The most prevalent polymers identified were polyethylene (PE), polypropylene (PP), polystyrene (PS), styrene−butadiene rubber (SBR), and natural rubber (NR). Statistical analyses, including principal component and cluster analysis, revealed size-dependent patterns,minor seasonal variation and spatial variations. These findings are particularly significant for ecotoxicological research and regulatory development, especially regarding tire abrasion a rarely quantified but potentially harmful MP source. The study contributes aluable data for future environmental monitoring and supports EU directives on wastewater and drinking water quality KW - TED-GC/MS KW - Microplastics KW - Environment KW - Monitoring KW - Reference data PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654669 DO - https://doi.org/10.1021/acsestwater.5c00530 SN - 2690-0637 SP - 1 EP - 10 PB - American Chemical Society (ACS) AN - OPUS4-65466 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna T1 - Textile Fibers as Reference Materials for Microplastic Release N2 - Fibers of textile origin are named as high contributor for microplastic pollution in the environment next to e.g. plastics from packaging, tire wear and paints. Small fibers and fragments (microplastics: 1-1000 µm) can be released from textiles by mechanical abrasion during application (e.g. wearing) or washing. To date, the occurrence, transport pathways, and impacts of such small fibers on the environment and human health remain unclear. The European Commission revised the Urban Wastewater Treatment Directive (Directive (EU) 2024/3019) and made monitoring of microplastics mandatory in the next years. Additionally, standards for microplastic detection are developed in the ISO standardization body ISO/TC 147/SC 2 with the documents ISO/DIS 16094-2 and ISO/DIS 16094-3. Detection mainly occurs by thermoanalytical methods for mass or vibrational methods with microscopes for numbers. Such standards and regulatory efforts need validated methods, which themselves need reference materials for validation. Reference materials are well characterized materials that are produced for a specific purpose and are homogeneous and stable within one property of interest. The shape and the composition of the reference particles/fibers will affect the detection, hence it is important to validate the instruments with fibers, if this is the task for monitoring campaigns. This work describes the production of realistic fibers as reference material for microplastic analysis. The individual samples contain of a small number (< 1000) and mass (< 20 µm) of fibres. Homogeneity and stability control occurred by thermogravimetric analysis and µ-Raman. Further characteristics were determined for type, shape and size distribution. T2 - TEXTEH CY - Bucharest, Romania DA - 23.10.2025 KW - Microplastics KW - Reference materials KW - Microfibers KW - Microfiber release PY - 2025 AN - OPUS4-64620 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Kittner, Maria A1 - Altmann, Korinna A1 - Hamann, Sven A1 - Weyer, Rüdiger A1 - Kalbe, Ute T1 - Bewertung der Freisetzung von Mikroplastik aus Sportböden auf Kunststoffbasis - Abschlussbericht N2 - Die Europäische Kommission hat 2023 ein Verbot zum bewussten Austrag von Mikroplastik (MP) in die Umwelt beschlossen, das auch für die Verwendung von synthetischen Gummi-Granulaten (v. a. EPDM) in Sportböden gilt. In Deutschland gibt es laut DFB ca. 5100 Kunstrasenplätze. In der EU beläuft sich die Anzahl laut ECHA auf 13,000 Kunstrasen- und 47,000 Bolzplätze, Tendenz steigend. Das Hauptziel des Projektes war es daher, eine Massenbilanz für die Freisetzung von MP zu erstellen, um so eine Schätzung des MP-Austrags pro Kunstrasenplatz und Jahr zu ermöglichen. Dafür werden die MP-Emissionen von drei Kunstrasenszenarien in verschiedenen Zuständen (ungealtert, künstlich gealtert und in Echtzeit gealtert) verglichen: die Vergangenheit (Kunstrasen: fossilbasiert, EPDM-Füllung), die Gegenwart (der in Europa am häufigsten installierte Rasen) und die Zukunft (Rasen mit recycelten Grasfasern, keine synthetische Füllung sondern z.B. Quarzsand oder Korkschrott). Dazu werden fabrikneue Kunststoffrasen und EPDM-Granulat unter Laborbedingungen beschleunigt gealtert, um die Freiland-Beanspruchung eines Kunststoffrasens in circa 15 Jahren abzubilden. Die Verwendung spezieller Mikrofiltertiegel in Lysimeter-Experimenten ermöglicht die Abschätzung der Partikelgrößen des emittierten MP, was eine Grundbedingung für die Bewertung einer potenziellen Gesundheitsgefährdung für Menschen ist. Ergänzend wurden weitere umweltrelevante Schadstoffausträge aus den Kunststoffrasen quantifiziert. KW - Mikroplastik KW - Kunststoffrasen KW - Schadstoffe KW - Bewitterung KW - Lysimeter PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-633114 DO - https://doi.org/10.26272/opus4-63311 N1 - Das Projekt wurde gefördert vom Bundesinstitut für Bau-, Stadt- und Raumforschung (BBSR) im Auftrag des Bundesministeriums für Wohnen, Stadtentwicklung und Bauwesen (BMWSB) aus Mitteln des Innovationsprogramms Zukunft Bau. Aktenzeichen: FKZ 10.08.18.7-22.02. Projektlaufzeit: 09.2022 bis 03.2025. SP - 1 EP - 75 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-63311 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Visileanu, Emilia A1 - Catalin Grosu, Marian A1 - Tiberiu Miclea, Paul A1 - Altmann, Korinna A1 - Brossell, Dirk T1 - Methods for the collection and characterization of airborne particles in the textile industry N2 - Airborne particulate matter is one of the main air pollutants. Their impact on mortality, and the occurrence of pulmonary and cardiovascular complications, have been the subject of numerous studies. Airborne particles are complex mixtures of organic and inorganic substances from different sources of particle emissions. Particulate Matter (PM) particles are classified according to their aerodynamic diameter expressed in µm and can vary from coarse (PM 10) to fine (less than PM 2.5). These diameter considerations are fundamental because they condition the penetration of particles into the bronchopulmonary system and the body. In recent years, there has been an interest in so-called “ultra-fine” particles, with a diameter of 0.1 µm (or 100 nm), or PM 0.1. They are nanoparticles and their impact on human health is not yet clear.With more than 1.5 million employees, textiles and clothing is a diverse sector that plays an important role in the European manufacturing industry, producing a turnover of €162 billion.An important component of the solid particles that generate air pollution in the textile industry is microplastics (MP) and nano plastics (NP), which also include microfibers (<5mm) and nanofibers (<100 nm), respectively. The particles released into the air during fiber and yarn processing range from 1 µg/m3 to 50 µg/m3.The paper presents the results of the determination of indoor and outdoor air concentration levels in textile companies, to identify the areas with the highest concentration level, by using an online recording system such as the Laser Aerosol Spectrometer MINI LAS model 11-E. The total concentration level TSP (µg/m3), the fractions PM 10(µg/m3), PM 2.5(µg/m3), PM1(µg/m3), as well as the total number of particles TC (1/l), were shown. It was noted that TSP is approximately at the same level both indoors and outdoors, but the fractions of PM10, PM2.5, and PM1 have much higher values indoors than outdoors with possible consequences on workers' health.The next step was the collection of fibers, namely micro and nano plastic particles from the vicinity of the workplaces of polyester, polyamide, and polypropylene fibers processing units in the textile industry in Romania, to obtain a sufficient quantity for laboratory analysis to determine the size and shape of the particles as well as their chemical composition. Two types of pumps were used, differentiated by their operating parameters: TECORA SKYPOST with airflow of 38 l/min and GILAIRPLUS with airflow 2l/min. Filters made of different materials with different diameters and pore sizes were used, namely: quartz filters (ø 47 mm, and ø 37 mm) on a TECORA SKYPOST type pump, polycarbonate nucleopore coated with a gold membrane (ø 25 mm) and silica filter (ø 9 mm) on GILAIRPLUS type pump.Using descriptive statistics, the calculation of correlation coefficients highlighted a strong correlation between the variables: "Collected mass/ Air concentration" and "Collected mass/ Air volume" for all diameters of the filters.The highest collected particle volume, determined by weighing the filters before and after collection, was obtained with the quartz filters (ø 47 mm) at an airflow of 38 l/min. The particles collected (polyester, polyamide, polypropylene) in the first stage were analyzed by SEM and thermogravimetric and it was found that the quartz filters absorbed the particles inside, with very few remaining on the surface. Thus no known methods can be used to perform analysis for particles collected on quartz filters. The number of particles on the filters was insufficient for analysis either because of the collection parameters used or because of the loss of particles during transport. As a result, in the next step, the use of 9 mm Si filters using the GILAIRPLUS pump at an airflow rate of 2l/min was chosen.To improve the transport conditions and avoid the loss of the particles and keep them on the surface of the filters, two methods were applied:- after weighing the filters were reintroduced into the collection pump holder;- a filtration system for airborne micro-nano plastics was designed and manufactured to selectively collect and transport PM10 and PM1 particles collected on SI filters.In both cases, SEM, Raman mapping, and GS-MS microscopy were used for analysis.Several times more PM10 than PM1 (74.5µg compared to 12.5 µg) was found. In all cases, both particles and fibers showed the same Raman fingerprint.The GS-MS analyses showed some contamination of the workspaces with particles other than the processed fibers. The presence of non-notifiable substances was also observed.The most viable filters are Si filters with a pore size of 10 microns to 1 micron and the use of the selected collection and transport filter system. In the following a filter system will be applied for collection on Au membrane-coated polycarbonate filters. T2 - 5th International Conference on Human Systems Engineering and Design: Future Trends and Applications (IHSED 2023) KW - Microplastics KW - Textiles PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624442 DO - https://doi.org/10.54941/ahfe1004132 VL - 112 SP - 212 EP - 223 PB - AHFE International AN - OPUS4-62444 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Ecke, Alexander T1 - Integrated Diagnostics of Pharmaceutical Contaminants in Water Supply and Management Systems N2 - The contamination of drinking water with pharmaceuticals represents a severe health risk. In order to monitor the drinking water quality continuously and enable quick countermeasures in case of contamination, novel sensors are required. Here, immunoanalytical methods based on the binding of the analyte to highly selective antibodies can be helpful. In this work, magnetic bead-based immunoassays (MBBAs) have been developed for the detection of two relevant contaminants of drinking water: diclofenac (DCF) and amoxicillin (AMX). In case of the latter, not only the parent drug is of interest in the risk assessment but also its hydrolysis products (HPs). In a comprehensive study, the influence of external factors and intrinsic properties of the water on the rate of hydrolysis was investigated. As the hydrolysis of AMX further impacts the recognition by the antibody, a strategy to analyze samples with unknown hydrolysis degree of AMX was established employing the enzyme β-lactamase in sample preparation. For both analytes, the MBBAs enable the fast quantification with results obtained in less than one hour which represents a major improvement over conventional immunoassays like the enzyme-linked immunosorbent assay (ELISA). Compared to the respective ELISAs with the same antibodies, the MBBAs further exhibit improved analytical parameters such as a broader measurement range and lower limits of detection. Due to the magnetic properties of the beads that serve as a platform for the assays, they are suitable for the mobile and automated detection at the point-of-care. An integrated diagnostic system was designed in which electrochemical detection with chronoamperometry on a microfluidic chip allows for further miniaturization of the system to enable monitoring of the drinking water quality online in water supply pipes at waterworks. N2 - Die Kontamination von Trinkwasser mit Arzneimitteln stellt eine ernste Gesundheitsgefahr dar. Um die Trinkwasserqualität kontinuierlich überwachen und im Falle einer Verunreinigung zeitnah reagieren zu können, sind neuartige Sensoren erforderlich. Hier können immunanalytische Methoden, die auf der Bindung des Analyten an hochselektive Antikörper beruhen, hilfreich sein. In dieser Arbeit wurden magnetpartikelbasierte Immunoassays (MBBAs) für zwei relevante Kontaminanten des Trinkwassers entwickelt: Diclofenac (DCF) und Amoxicillin (AMX). Bei letzterem erwiesen sich neben der Ausgangsverbindung auch dessen Hydrolyseprodukte (HPs) als relevant für die Gefährdungsbeurteilung. In einer umfassenden Studie wurde der Einfluss von externen Faktoren und intrinsischen Eigenschaften des Wassers auf die Hydrolysegeschwindigkeit untersucht. Da die Hydrolyse von AMX auch die Erkennung durch den Antikörper beeinflusst, wurde eine Strategie zur Analyse von Proben mit unbekanntem Hydrolysegrad von AMX unter Verwendung des Enzyms β-Lactamase in der Probenvorbereitung entwickelt. Für beide Analyten ermöglichen die MBBAs eine schnelle Quantifizierung mit Ergebnissen in weniger als einer Stunde, was eine wesentliche Verbesserung gegenüber herkömmlichen Immunoassays wie dem Enzyme-linked Immunosorbent Assay (ELISA) darstellt. Im Vergleich zu den entsprechenden ELISAs mit denselben Antikörpern weisen die MBBAs zudem verbesserte analytische Parameter auf, wie einen breiteren Messbereich und niedrigere Nachweisgrenzen. Aufgrund der magnetischen Eigenschaften der Partikel, die als Plattform für die Assays dienen, eignen sie sich für den mobilen und automatisierten Einsatz vor Ort. Ein integriertes Diagnosesystem, bei dem die elektrochemische Detektion mittels Chronoamperometrie auf einem mikrofluidischen Chip eine weitere Miniaturisierung des Systems ermöglicht, wurde entworfen, um die Überwachung der Trinkwasserqualität online in Wasserwerken zu ermöglichen. KW - Antibiotics KW - Immunoassay KW - Amoxicillin KW - Diclofenac KW - Biosensor KW - Antibodies PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591901 DO - https://doi.org/10.18452/25853 SP - 1 EP - 129 CY - Berlin AN - OPUS4-59190 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kader, A. A1 - Snellings, J. A1 - Adams, L. C. A1 - Gottheil, P. A1 - Mangarova, D. B. A1 - Heyl, J. L. A1 - Kaufmann, Jan Ole A1 - Moeckel, J. A1 - Brangsch, J. A1 - Auer, T. A. A1 - Collettini, F. A1 - Sauer, F. A1 - Hamm, B. A1 - Käs, J. A1 - Sack, I. A1 - Makowski, M. R. A1 - Braun, J. T1 - Sensitivity of magnetic resonance elastography to extracellular matrix and cell motility in human prostate cancer cell line-derived xenograft models N2 - Prostate cancer (PCa) is a significant health problem in the male population of the Western world. Magnetic resonance elastography (MRE), an emerging medical imaging technique sensitive to mechanical properties of biological tissues, detects PCa based on abnormally high stiffness and viscosity values. Yet, the origin of these changes in tissue properties and how they correlate with histopathological markers and tumor aggressiveness are largely unknown, hindering the use of tumor biomechanical properties for establishing a noninvasive PCa staging system. To infer the contributions of extracellular matrix (ECM) components and cell motility, we investigated fresh tissue specimens from two PCa xenograft mouse models, PC3 and LNCaP, using magnetic resonance elastography (MRE), diffusion-weighted imaging (DWI), quantitative histology, and nuclear shape analysis. Increased tumor stiffness and impaired water diffusion were observed to be associated with collagen and elastin accumulation and decreased cell motility. Overall, LNCaP, while more representative of clinical PCa than PC3, accumulated fewer ECM components, induced less restriction of water diffusion, and exhibited increased cell motility, resulting in overall softer and less viscous properties. Taken together, our results suggest that prostate tumor stiffness increases with ECM accumulation and cell adhesion - characteristics that influence critical biological processes of cancer development. MRE paired with DWI provides a powerful set of imaging markers that can potentially predict prostate tumor development from benign masses to aggressive malignancies in patients. Statement of significance: Xenograft models of human prostate tumor cell lines, allowing correlation of microstructure-sensitive biophysical imaging parameters with quantitative histological methods, can be investigated to identify hallmarks of cancer. KW - Magnetic resonance elastography KW - Quantitative histology KW - Prostate cancer KW - Stiffness KW - Fluidity KW - Apparent diffusion coefficient KW - Collagen KW - Elastin KW - Nuclear shape PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618361 DO - https://doi.org/10.1016/j.bioadv.2024.213884 SN - 2772-9508 VL - 161 SP - 1 EP - 12 PB - Elsevier CY - Amsterdam AN - OPUS4-61836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mangarova, Dilyana Branimirova A1 - Reimann, Carolin A1 - Kaufmann, Jan Ole A1 - Möckel, Jana A1 - Kader, Avan A1 - Adams, Lisa Christine A1 - Ludwig, Antje A1 - Onthank, David A1 - Robinson, Simon A1 - Karst, Uwe A1 - Helmer, Rebecca A1 - Botnar, Rene A1 - Hamm, Bernd A1 - Makowski, Marcus Richard A1 - Brangsch, Julia T1 - Elastin-specific MR probe for visualization and evaluation of an interleukin-1β targeted therapy for atherosclerosis N2 - Atherosclerosis is a chronic inflammatory condition of the arteries and represents the primary cause of various cardiovascular diseases. Despite ongoing progress, finding effective anti-inflammatory therapeutic strategies for atherosclerosis remains a challenge. Here, we assessed the potential of molecular magnetic resonance imaging (MRI) to visualize the effects of 01BSUR, an anti-interleukin-1β monoclonal antibody, for treating atherosclerosis in a murine model. Male apolipoprotein E-deficient mice were divided into a therapy group (01BSUR, 2 × 0.3 mg/kg subcutaneously, n = 10) and control group (no treatment, n = 10) and received a high-fat diet for eight weeks. The plaque burden was assessed using an elastin-targeted gadolinium-based contrast probe (0.2 mmol/kg intravenously) on a 3 T MRI scanner. T1-weighted imaging showed a significantly lower contrast-to-noise (CNR) ratio in the 01BSUR group (pre: 3.93042664; post: 8.4007067) compared to the control group (pre: 3.70679168; post: 13.2982156) following administration of the elastin-specific MRI probe (p < 0.05). Histological examinations demonstrated a significant reduction in plaque size (p < 0.05) and a significant decrease in plaque elastin content (p < 0.05) in the treatment group compared to control animals. This study demonstrated that 01BSUR hinders the progression of atherosclerosis in a mouse model. Using an elastin-targeted MRI probe, we could quantify these therapeutic effects in MRI. N2 - Atherosklerose ist eine chronische entzündliche Erkrankung der Arterien und die Hauptursache für verschiedene Herz-Kreislauf-Erkrankungen. Trotz kontinuierlicher Fortschritte ist es nach wie vor schwierig, wirksame entzündungshemmende Therapiestrategien für Atherosklerose zu finden. In dieser Studie haben wir das Potenzial der molekularen Magnetresonanztomographie (MRT) zur Visualisierung der Wirkung von 01BSUR, einem monoklonalen Anti-Interleukin-1β-Antikörper, zur Behandlung von Atherosklerose in einem Mausmodell untersucht. Männliche Apolipoprotein-E-defiziente Mäuse wurden in eine Therapiegruppe (01BSUR, 2 × 0,3 mg/kg subkutan, n = 10) und eine Kontrollgruppe (keine Behandlung, n = 10) aufgeteilt und erhielten acht Wochen lang eine fettreiche Diät. Die Plaquebelastung wurde mit einer auf Elastin ausgerichteten Kontrastmittelsonde auf Gadoliniumbasis (0,2 mmol/kg intravenös) auf einem 3-T-MRT-Scanner untersucht. Die T1-gewichtete Bildgebung zeigte ein signifikant niedrigeres Kontrast-Rausch-Verhältnis (CNR) in der 01BSUR-Gruppe (vorher: 3,93042664; nachher: 8,4007067) im Vergleich zur Kontrollgruppe (vorher: 3,70679168; nachher: 13,2982156) nach Verabreichung der Elastin-spezifischen MRT-Sonde (p < 0,05). Histologische Untersuchungen zeigten eine signifikante Verringerung der Plaque-Größe (p < 0,05) und eine signifikante Abnahme des Plaque-Elastin-Gehalts (p < 0,05) in der Behandlungsgruppe im Vergleich zu den Kontrolltieren. Diese Studie zeigte, dass 01BSUR das Fortschreiten der Atherosklerose in einem Mausmodell hemmt. Mit einer auf Elastin ausgerichteten MRT-Sonde konnten wir diese therapeutischen Effekte in der MRT quantifizieren. KW - Atherosclerosis KW - Molecular imaging KW - Elastin KW - Plaque KW - Interleukin-1beta PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610858 DO - https://doi.org/10.1038/s41598-024-71716-5 VL - 14 IS - 1 SP - 1 EP - 11 PB - Springer Science and Business Media LLC AN - OPUS4-61085 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 - Dittmar, Stefan A1 - Weyrauch, Steffen A1 - Reemtsma, Thorsten A1 - Eisentraut, Paul A1 - Altmann, Korinna A1 - Ruhl, Aki S. A1 - Jekel, Martin T1 - Settling Velocities of Tire and Road Wear Particles: Analyzing Finely Graded Density Fractions of Samples from a Road Simulator and a Highway Tunnel N2 - The terminal settling velocity is considered the most critical parameter determining the transport of tire and road wear particles (TRWP) in aquatic environments. Nonetheless, no respective empirical data has been reported so far. In this study, particle samples from a road simulator and a highway tunnel were investigated with a validated imaging method. Different density and size fractions of both samples were measured separately, acquiring sizes and settling velocities of more than 30,000 individual particles. In addition, tire marker polymers were analyzed for each fraction via thermal extraction desorption-gas chromatography/mass spectrometry. Finally, the acquired particle data was combined according to the fractions’ estimated tire contents in order to deduce detailed probability distributions of particle size and settling velocity for the actual TRWP from both samples. Weighted by TRWP-incorporated tire mass, median diameters of 54 and 44 μm as well as median settling velocities of 0.65 and 0.22 mm/s were found for TRWP from the road simulator and highway tunnel, respectively. This study thus provides the first ever empirical data on TRWP settling velocities in water, which can be highly valuable input for modeling the environmental transport of TRWP and for dimensioning TRWP retention systems. KW - Microplastics KW - TED-GC/MS KW - Sinking velocities KW - Transport PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-635449 DO - https://doi.org/10.1021/acs.est.5c04165 SN - 0013-936X VL - 59 IS - 26 SP - 13434 EP - 13446 PB - American Chemical Society (ACS) AN - OPUS4-63544 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Visileanu, Emilia A1 - Altmann, Korinna A1 - Stepa, Raluca A1 - Haiducu, Maria A1 - Miclea, Paul Tiberiu A1 - Vladu, Alina A1 - Dondea, Felicia A1 - Grosu, Marian Catalin A1 - Scarlat, Razvan T1 - Comparative Analysis of Airborne Particle Concentrations in Textile Industry Environments Throughout the Workday N2 - This paper addresses the growing concern surrounding microplastic pollution, particularly within the textile industry, and the associated potential health risks linked to the inhalation and ingestion of microplastic particles. Microplastics, defined as plastic particles smaller than five millimeters, are increasingly found not only in aquatic environments, but also in soils, air, and food. Although research on the health impacts of microplastics is still emerging, early studies indicate that these particles could contribute to health issues, including oxidative stress, inflammation, and cardiovascular diseases. Notably, individuals with higher concentrations of plastics in arterial plaques are more susceptible to heart attacks and strokes. In the textile industry, synthetic fibers such as polyester, nylon, and acrylic release microplastics into the air during production. The paper discusses a study conducted in a textile company that processes polyester yarns, where airborne microplastic concentrations were measured at various locations throughout the day. Particle sizes ranging from 0.3 nm to 10 nm were analyzed, revealing the presence of polyester polymers in the particulate matter. These findings underscore the widespread nature of microplastic pollution, particularly in industrial settings, and raise concerns about the health risks associated with prolonged exposure to airborne microplastics. While further research is necessary to fully understand the extent of these health impacts, preliminary data suggest a troubling link between microplastic inhalation and cardiovascular conditions. KW - Microplastics KW - Textiles KW - Airborne particles PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-635269 DO - https://doi.org/10.3390/microplastics4020034 SN - 2673-8929 VL - 4 IS - 2 SP - 1 EP - 17 PB - MDPI AG AN - OPUS4-63526 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiesner, Yosri A1 - Bednarz, Marius A1 - Braun, Ulrike A1 - Bannick, Claus Gerhard A1 - Ricking, Mathias A1 - Altmann, Korinna T1 - A promising approach to monitor microplastic masses in composts N2 - Inputs of plastic impurities into the environment via the application of fertilizers are regulated in Germany and the EU by means of ordinances. Robust and fast analytical methods are the basis of legal regulations. Currently, only macro- and large microplastic contents (>1 mm) are measured. Microplastics (1–1,000 µm), are not yet monitored. Thermal analytical methods are suitable for this purpose, which can determine the mass content and can also be operated fully automatically in routine mode. Thermal extraction desorption-gas chromatography/mass spectrometry (TED-GC/MS) allows the identification of polymers and the determination of mass contents in solid samples from natural environments. In accordance with the German or European Commission (EC) Fertiliser Ordinance, composting plants should be monitored for microplastic particles with this method in the future. In this context a compost plant was sampled. At the end of the rotting process, the compost was sieved and separated in a coarse (>1 mm) and a fine fraction (<1 mm). The fine fraction was processed using density separation comparing NaCl and NaI as possible salt alternative and screened for microplastic masses by TED-GC/MS with additional validation and quality assurance experiments. With TED-GC/MS total microplastics mass contents of 1.1–3.0 μg/mg in finished compost could be detected with polyethylene mainly. What differs much to the total mass of plastics in the coarse fraction with up to 60 μg/mg, which were visually searched, identified via ATR-FTIR and gravimetrically weighted. KW - Microplastics KW - TED-GC/MS KW - Compost KW - Monitoring KW - Soil PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-586688 DO - https://doi.org/10.3389/fenvc.2023.1281558 SN - 2673-4486 VL - 4 SP - 1 EP - 12 PB - Frontiers Media CY - Lausanne AN - OPUS4-58668 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Schwaar, Timm T1 - Entwicklung von multidimensionalen Hochdurchsatzmethoden zur Analyse von Partikel-basierten Peptidbibliotheken N2 - Gegenwärtig ist das Interesse und der Bedarf von Proteinbindern insbesondere in der Biotechnik und Pharmaforschung sehr groß. Kombinatorische, Partikel-basierte (One-Bead-One-Compound) Peptidbibliotheken sind eine Technik, um selektiv bindende Proteine zu identifizieren. Allerdings beinhaltet das Screening dieser Peptidbibliotheken aufwendige Schritte, wie die Separation, Sequenzierung und Charakterisierung von identifizierten Bindern. In dieser Arbeit wurde ein Chip-System entwickelt, auf dem alle Schritte eines Screenings durchgeführt werden können. Dafür wurde ein Glasobjektträger mit einem magnetisch leitenden, doppelseitigen Klebeband versehen. Die Partikel der Bibliothek wurden durch ein Sieb aufgetragen. Dies führte zu einer geordneten Immobilisierung der Partikel auf dem Chip. Über 30.000 Partikel konnten so auf einem Chip immobilisiert werden. Für die Identifizierung von selektiven Protein-bindenden Peptiden wird die immobilisierte Peptidbibliothek mit einem Fluorophor-markierten Protein inkubiert, bindende Partikel mittels Fluoreszenzscan identifiziert und die Peptidsequenz direkt auf dem Chip mittels Matrix-Assisted-Laser-Desorption/Ionization-(MALDI)-Flugzeit-(TOF)-Massenspektroskopie (MS) bestimmt. Die Durchführung einer Abbruchsequenz-Methode erlaubt die eindeutige Bestimmung der Peptidsequenzen mit einer nahezu 100 % Genauigkeit. Die entwickelte Technologie wurde in einem FLAG-Peptid-Modell validiert. Bei dem Screening wurden neue anti-FLAG-Antikörper-bindende Peptide identifiziert. Anschließend wurden in einem Screening von ca. 30.000 Partikeln IgG-bindende Peptide mit mittleren mikromolaren Dissoziationskonstanten identifiziert. Für die Identifizierung stärkerer Binder wurde eine magnetische Anreicherung entwickelt, die dem Chip-Screening vorgeschaltet werden kann. Hiermit wurden aus ca. 1 Million gescreenter Partikel, Peptide mit Dissoziationskonstanten im niedrigen mikromolaren Bereich identifiziert. N2 - The screening of one-bead-one-compound (OBOC) libraries is a well-established technique for the identification of protein-binding ligands. The demand for binders with high affinity and specificity towards various targets has surged in the biomedical and pharmaceutical field in recent years. The combinatoric peptide screening traditionally involves tedious steps such as affinity selection, bead picking, sequencing and characterization. In this thesis, a high-throughput “all-on-one chip” system is presented to avoid slow and technically complex bead picking steps. Beads of a combinatorial peptide library are immobilized on a conventional glass slide equipped with an electrically conductive tape. The beads are applied by using a precision sieve, which allows the spatially ordered immobilization of more than 30,000 beads on one slide. For the target screening, the immobilized library is subsequently incubated with a fluorophore-labeled target protein. In a fluorescence scan followed by matrix-assisted laser desorption/ionization (MALDI)-time of flight (TOF) mass spectrometry (MS), high-affinity binders are directly and unambiguously sequenced directly from the bead. The use of an optimized ladder sequencing approach improved the accuracy of the de-novo sequencing step to 100 %. This new technique was validated by employing a FLAG-based model system. In a first step, new peptide binders for the M2 anti-FLAG monoclonal antibody were identified. Finally, this system was utilized to screen for IgG-binding peptides. The screening of about 30.000 peptides on one chip led to the identification of peptide binders in the mid micromolar range. A magnetic enrichment technique was developed to increase the number of screened beads. By combining the magnetic enrichment strategy with the chip system, 1 million beads were screened and IgG-binders in the low micromolar range were identified. KW - Peptidbibliotheken KW - Hochdurchsatzscreening KW - Peptidsequenzierung KW - Chip-Screening PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511649 DO - https://doi.org/10.18452/21793 SP - 1 EP - 153 PB - Humboldt-Universität CY - Berlin AN - OPUS4-51164 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Paul, Martin A1 - Tscheuschner, Georg A1 - Herrmann, Stefan A1 - Weller, Michael G. T1 - Fast Detection of 2,4,6-Trinitrotoluene (TNT) at ppt Level by a Laser-Induced Immunofluorometric Biosensor N2 - The illegal use of explosives by terrorists and other criminals is an increasing issue in public spaces, such as airports, railway stations, highways, sports venues, theaters, and other large buildings. Security in these environments can be achieved by different means, including the installation of scanners and other analytical devices to detect ultra-small traces of explosives in a very short time-frame to be able to take action as early as possible to prevent the detonation of such devices. Unfortunately, an ideal explosive detection system still does not exist, which means that a compromise is needed in practice. Most detection devices lack the extreme analytical sensitivity, which is nevertheless necessary due to the low vapor pressure of nearly all explosives. In addition, the rate of false positives needs to be virtually zero, which is also very difficult to achieve. Here we present an immunosensor system based on kinetic competition, which is known to be very fast and may even overcome affinity limitation, which impairs the performance of many traditional competitive assays. This immunosensor consists of a monolithic glass column with a vast excess of immobilized hapten, which traps the fluorescently labeled antibody as long as no explosive is present. In the case of the explosive 2,4,6-trinitrotoluene (TNT), some binding sites of the antibody will be blocked, which leads to an immediate breakthrough of the labeled protein, detectable by highly sensitive laser-induced fluorescence with the help of a Peltier-cooled complementary metal-oxide-semiconductor (CMOS) camera. Liquid handling is performed with high-precision syringe pumps and chip-based mixing-devices and flow-cells. The system achieved limits of detection of 1 pM (1 ppt) of the fluorescent label and around 100 pM (20 ppt) of TNT. The total assay time is less than 8 min. A cross-reactivity test with 5000 pM solutions showed no signal by pentaerythritol tetranitrate (PETN), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). This immunosensor belongs to the most sensitive and fastest detectors for TNT with no significant cross-reactivity by non-related compounds. The consumption of the labeled antibody is surprisingly low: 1 mg of the reagent would be sufficient for more than one year of continuous biosensor operation. KW - Airport KW - Aviation KW - Bombs KW - Terrorism KW - Biosensing KW - Continuous Sensor KW - High-Speed KW - Ultrasensitive PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511245 DO - https://doi.org/10.3390/bios10080089 VL - 10 IS - 8 SP - 89 PB - MDPI CY - Basel AN - OPUS4-51124 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Costa, Elena A1 - Climent Terol, Estela A1 - Gawlitza, Kornelia A1 - Wan, Wei A1 - Weller, Michael G. A1 - Rurack, Knut T1 - Optimization of analytical assay performance of antibody-gated indicator-releasing mesoporous silica particles N2 - Antibody-gated indicator delivery (gAID) systems based on mesoporous silica nano- and microparticle scaffolds are a promising class of materials for the sensitive chemical detection of small-molecule analytes in simple test formats such as lateral flow assays (LFAs) or microfluidic chips. Their architecture is reminiscent of drug delivery systems, only that reporter molecules instead of drugs are stored in the voids of a porous host particle. In addition, the pores are closed with macromolecular “caps” through a tailored “gatekeeping” recognition chemistry so that the caps are opened when an analyte has reacted with a “gatekeeper”. The subsequent uncapping leads to a release of a large number of indicator molecules, endowing the system with signal amplification features. Particular benefits of such systems are their modularity and adaptability. With the example of the immunochemical detection of type-I pyrethroids by fluorescent dye-releasing gAID systems, the influence of several tuning modes on the optimisation of such hybrid sensory materials is introduced here. In particular, different mesoporous silica supports (from nano- and microparticles to platelets and short fibres), different functionalisation routes and different loading sequences were assessed. The materials’ performances were evaluated by studying their temporal response behaviour and detection sensitivity, including the tightness of pore closure (through the amount of blank release in the absence of analyte) and the release kinetics. Our results indicate that the better the paratope-accommodating Fab region of the antibody “cap” fits into the host material's pore opening, the better the closing/opening mechanism can be controlled. Because such materials are well-suited for LFAs, performance assessment included a test-strip format besides conventional assays in suspension. In combination with dyes as indicators and smartphones for read-out, simple analytical tests for use by untrained personnel directly at a point-of-need such as an aeroplane cabin can be devised, allowing for sensitivities down to the μg kg−1 range in <5 min with case-required selectivities. KW - Antibody-gated indicator delivery KW - Lateral flow assay KW - SBA-15 KW - SBA-16 KW - Type-I pyrethroids KW - Phenothrin KW - Permethrin KW - Etofenprox KW - Amplification KW - Biosensors KW - Immunoassays KW - Mesoporous particles KW - Optical detection PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517053 DO - https://doi.org/10.1039/d0tb00371a VL - 8 IS - 22 SP - 4950 EP - 4961 PB - Royal Society of Chemistry AN - OPUS4-51705 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 - 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 - JOUR A1 - Brangsch, J. A1 - Reimann, C. A1 - Kaufmann, Jan Ole A1 - Adams, L. C. A1 - Onthank, D. A1 - Thöne-Reineke, C. A1 - Robinson, S. A1 - Ponader, Marco A1 - Weller, Michael G. A1 - Buchholz, R. A1 - Karst, U. A1 - Botnar, R. A1 - Hamm, B. A1 - Makowski, M. R. T1 - Molecular MR-Imaging for Noninvasive Quantification of the Anti-Inflammatory Effect of Targeting Interleukin-1β in a Mouse Model of Aortic Aneurysm N2 - Background: Molecular-MRI is a promising imaging modality for the assessment of abdominal aortic aneurysms (AAAs). Interleukin-1β (IL-1β) represents a new therapeutic tool for AAA-treatment, since pro-inflammatory cytokines are key-mediators of inflammation. This study investigates the potential of molecular-MRI to evaluate therapeutic effects of an anti-IL-1β-therapy on AAA-formation in a mouse-model. Methods: Osmotic-minipumps were implanted in apolipoprotein-deficient-mice (N = 27). One group (Ang-II+01BSUR group, n = 9) was infused with angiotensin-II (Ang-II) for 4 weeks and received an anti-murine IL-1β-antibody (01BSUR) 3 times. One group (Ang-II-group, n = 9) was infused with Ang-II for 4 weeks but received no treatment. Control-group (n = 9) was infused with saline and received no treatment. MR-imaging was performed using an elastin-specific gadolinium-based-probe (0.2 mmol/kg). Results: Mice of the Ang-II+01BSUR-group showed a lower aortic-diameter compared to mice of the Ang-II-group and control mice (p < 0.05). Using the elastin-specific-probe, a significant decrease in elastin-destruction was observed in mice of the Ang-II+01BSUR-group. In vivo MR-measurements correlated well with histopathology (y = 0.34x-13.81, R2 = 0.84, p < 0.05), ICP-MS (y = 0.02x+2.39; R2 = 0.81, p < 0.05) and LA-ICP-MS. Immunofluorescence and western-blotting confirmed a reduced IL-1β-expression. Conclusions: Molecular-MRI enables the early visualization and quantification of the anti-inflammatory-effects of an IL-1β-inhibitor in a mouse-model of AAAs. Responders and non-responders could be identified early after the initiation of the therapy using molecular-MRI. KW - Cardiovascular KW - Molecular-MRI KW - Magnetic resonance imaging KW - Gadolinium-based contrast agent KW - Elastin-specific contrast agent ESMA KW - Gadovist KW - Gadofosveset KW - MR Angiography KW - Inductively Coupled Mass Spectroscopy KW - Element Specific Bioimaging Using Laser Ablation KW - Visualization PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517150 DO - https://doi.org/10.1177/1536012120961875 N1 - Geburtsname von Ponader, Marco: Wilke, M. - Birth name of Ponader, Marco: Wilke, M. VL - 19 SP - 61875 PB - SAGE AN - OPUS4-51715 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Axel A1 - Altmann, Korinna A1 - Kocher, B. A1 - Braun, U. T1 - Determination of tire wear markers in soil samples and their distribution in a roadside soil N2 - Tire wear (TW) constitutes a significant source of microplastic in terrestrial ecosystems. It is known that particles emitted by roads can have an effect up to 100 m into adjacent areas. Here, we apply for the first-time thermal extraction desorption gas chromatography-mass spectrometry (TED-GC/MS) to determine TW in soil samples by detection of thermal decomposition products of styrene-butadiene rubber (SBR), without additional enrichment. Additionally, zinc contents were determined as an elemental marker for TW. Mixed soil samples were taken along three transects along a German motorway in 0.3, 2.0, and 5.0 m distance from the road. Sampling depths were 0–2, 2–5, 5–10, and 10–20 cm. Four fine fractions, 1 000–500, 500–100, 100–50, and <50 μm, were analyzed. TW contents based on SBR ranged from 155 to 15 898 mg kg−1. TW contents based on zinc were between 413 and 44 812 mg kg−1. Comparison of individual values of SBR and zinc reveals SBR as a more specific marker. Results confirm that most TW ends up in the topsoil within a 2 m distance. The sampling strategy resulted in representative data for a larger area. Standard deviations of quadruple TED-GC/MS determination of SBR were <10% for all grain size fractions. TED-GC/MS is a suitable analytical tool for determining TW in soil samples without the use of toxic chemicals, enrichment, or special sample preparation. KW - Microplastic KW - TED-GC/MS KW - Tire wear PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543344 DO - https://doi.org/10.1016/j.chemosphere.2022.133653 VL - 294 SP - 1 EP - 8 PB - Elsevier Ltd. AN - OPUS4-54334 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Senges, Gene A1 - de Oliveira Guilherme Buzanich, Ana A1 - Lindič, Tilen A1 - Gully, Tyler A. A1 - Winter, Marlon A1 - Radtke, Martin A1 - Röder, Bettina A1 - Steinhauer, Simon A1 - Paulus, Beate A1 - Emmerling, Franziska A1 - Riedel, Sebastian T1 - Unravelling highly oxidized nickel centers in the anodic black film formed during the Simons process by in situ X-ray absorption near edge structure spectroscopy N2 - The electrofluorination after Simons has been used for the last century to produce everyday life materials. An in situ XANES investigation of the controversially debated black film apparent in the Simons process revealed high-valent nickel centers. KW - Synchrotron KW - BAMline KW - XANES PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608366 DO - https://doi.org/10.1039/d3sc06081k SN - 2041-6520 VL - 15 IS - 12 SP - 4504 EP - 4509 PB - Royal Society of Chemistry (RSC) AN - OPUS4-60836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fischer, Janina A1 - Kaufmann, Jan Ole A1 - Weller, Michael G. T1 - Simple Determination of Affinity Constants of Antibodies by Competitive Immunoassays N2 - The affinity constant, also known as the equilibrium constant, binding constant, equilibrium association constant, or the reciprocal value, the equilibrium dissociation constant (Kd), can be considered as one of the most important characteristics for any antibody–antigen pair. Many methods based on different technologies have been proposed and used to determine this value. However, since a very large number of publications and commercial datasheets do not include this information, significant obstacles in performing such measurements seem to exist. In other cases where such data are reported, the results have often proved to be unreliable. This situation may indicate that most of the technologies available today require a high level of expertise and effort that does not seem to be available in many laboratories. In this paper, we present a simple approach based on standard immunoassay technology that is easy and quick to perform. It relies on the effect that the molar IC50 approaches the Kd value in the case of infinitely small concentrations of the reagents. A two-dimensional dilution of the reagents leads to an asymptotic convergence to Kd. The approach has some similarity to the well-known checkerboard titration used for the optimization of immunoassays. A well-known antibody against the FLAG peptide, clone M2, was used as a model system and the results were compared with other methods. This approach could be used in any case where a competitive assay is available or can be developed. The determination of an affinity constant should belong to the crucial parameters in any quality control of antibody-related products and assays and should be mandatory in papers using immunochemical protocols. N2 - Die Affinitätskonstante, auch bekannt als Gleichgewichtskonstante, Bindungskonstante, Gleichgewichtsassoziationskonstante oder der reziproke Wert, die Gleichgewichtsdissoziationskonstante (Kd), kann als eine der wichtigsten Eigenschaften für jedes Antikörper-Antigen-Paar angesehen werden. Zur Bestimmung dieses Wertes wurden zahlreiche Methoden auf der Grundlage verschiedener Technologien vorgeschlagen und verwendet. Da jedoch eine sehr große Anzahl von Veröffentlichungen und kommerziellen Datenblätter diese Information nicht enthalten, scheint es erhebliche Hindernisse bei der Durchführung solcher Messungen zu geben. In anderen Fällen, in denen solche Daten angegeben werden, haben sich die Ergebnisse häufig als unzuverlässig erwiesen. Diese Situation könnte darauf hindeuten, dass die meisten der heute verfügbaren Technologien ein hohes Maß an Fachwissen und Aufwand erfordern, das in vielen Labors nicht vorhanden zu sein scheint. In diesem Beitrag stellen wir einen einfachen Ansatz vor, der auf der Standard-Immunoassay-Technologie basiert und einfach und schnell durchführbar ist. Er beruht auf dem Effekt, dass sich der molare IC50 bei unendlich kleinen Reagenz-Konzentrationen dem Kd-Wert annähert. Eine zweidimensionale Verdünnung der Reagenzien führt zu einer asymptotischen Konvergenz zu Kd. Der Ansatz hat eine gewisse Ähnlichkeit mit der bekannten Checkerboard-Titration, die zur Optimierung von Immunoassays verwendet wird. Ein bekannter Antikörper gegen das FLAG-Peptid, Klon M2, wurde als Modellsystem verwendet, und die Ergebnisse wurden mit anderen Methoden verglichen. Dieser Ansatz kann überall dort angewendet werden, wo ein kompetitiver Assay verfügbar ist oder entwickelt werden kann. Die Bestimmung einer Affinitätskonstante sollte zu den entscheidenden Parametern bei der Qualitätskontrolle von Antikörperprodukten und -assays gehören und in Arbeiten, die immunchemische Protokolle verwenden, obligatorisch sein. KW - ELISA KW - Competitive immunoassay KW - IC50 KW - Test midpoint KW - Point of inflection KW - Equilibrium constant KW - Dissociation constant KW - Binding strength KW - Antibody antigen complex KW - Bio-interaction KW - SPR KW - Surface-plasmon resonance KW - FLAG peptide KW - Clone M2 KW - Antibody quality PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605607 DO - https://doi.org/10.3390/mps7030049 SN - 2409-9279 VL - 7 IS - 3 SP - 1 EP - 11 PB - MDPI CY - Basel AN - OPUS4-60560 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Monikh, Fazel A. A1 - Materić, Dušan A1 - Valsami-Jones, Eugenia A1 - Grossart, Hans-Peter A1 - Altmann, Korinna A1 - Holzinger, Rupert A1 - Lynch, Iseult A1 - Stubenrauch, Jessica A1 - Peijnenburg, Willie T1 - Challenges in studying microplastics in human brain N2 - Human exposure to microplastics and nanoplastics (MNPs) is an emerging concern with potential implications for health. As awareness of this issue grows, it has prompted increasing scientific attention toward understanding if, and how, MNPs accumulate in human tissues. In a recent study, Nihart et al.1 used the analytical technique of pyrolysis gas chromatography–mass spectrometry (Py-GC–MS) to detect MNPs in human liver, kidney and brain, reporting the highest concentrations in the brain, with polyethylene as the predominant polymer. The study as reported appears to face methodological challenges, such as limited contamination controls and lack of validation steps, which May affect the reliability of the reported concentrations. In this Matters Arising, we highlight methodological limitations that have General relevance for advancing robust and reproducible MNP detection in human biomonitoring studies. KW - Microplastics KW - Nanoplastics KW - Py-GC-MS PY - 2025 DO - https://doi.org/10.1038/s41591-025-04045-3 SN - 1078-8956 VL - 31 IS - 12 SP - 1 EP - 3 PB - Springer Science and Business Media LLC AN - OPUS4-64698 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna T1 - Seasonal microplastic concentrations along the rivers Rhine and Danube N2 - Over the last 20 years, many researchers, politicians and citizens have become increasingly aware of the growing plastic problem of our time. A lack of recycling concepts and plastic collection points as well as careless dumping lead to accumulation of plastic products in the environment. Natural weathering can cause these plastics to degrade and fractionate, meaning that microplastics (1 1,000 µm, ISO/TR 21960:2020) and nanoplastics (< 1 µm, ISO/TR 21960:2020) of various synthetic polymer materials can now be detected in all parts of the world. Whether microplastics or nanoplastics pose a toxicological hazard is being investigated in a variety of ways. Valid results are still pending. However, the EU precautionary principle applies to micro- and nanoplastics. Monitoring of microplastics is already required in the revision of the Drinking Water and Wastewater Framework Directive. Reliable monitoring of rivers can be carried out by sampling with sedimentation boxes and microplastic detection by using thermal extraction desorption gas chromatography/mass spectrometry (TED-GC/MS) in routine operation (Figure 1). The river Rhine was sampled for microplastic masses at three different sampling locations over a period of one year and in addition the Danube at randomized sampling locations The TED-GC/MS results showed that various synthetic polymers frequently produced in industry, such as polyethylene, polypropylene or polystyrene as well as the tire compound styrene-butadiene rubber were found. The work not only shows a possible workflow for monitoring concepts, but also provides information on environmentally relevant concentrations of microplastics and tire components in surface waters. This in turn is necessary for ecotoxicological studies. T2 - ESOPS CY - Berlin, Germany DA - 09.09.2024 KW - Microplastics KW - TED-GC/MS KW - Polymer 3R PY - 2024 AN - OPUS4-61016 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Atanasova, Aleksandra T1 - Herstellung und Einsatz neuartiger Trypsin-Partikel für den enzymatischen Antikörper-Verdau N2 - In dieser Arbeit wurden zwei Trypsinvarianten, der Wildtyp (wtT) und eine thermostabile Variante (tsT), rekombinant hergestellt. Die Herstellung von Proteinen in Bakterien kann zu Fehlfaltungen und Einschlusskörperchen führen, weshalb eine geeignete Faltungsstrategie notwendig ist. In dieser Arbeit konnte eine schrittweise Vorgehensweise erfolgreich angewendet werden. Nach der Ni-NTA-Aufreinigung wurde zusätzlich eine substratspezifische Benzamidin-Aufreinigung eingesetzt, um die Aktivität zu verbessern. Außerdem wurden die rekombinanten Trypsine auf Korund immobilisiert. Korund ist ein kostengünstiges Material, das nach Silanisierung und Glutaraldehyd-Kopplung für die Bindung von Proteinen geeignet gemacht wurde. Dabei konnte gezeigt werden, dass mehr wtT als tsT gebunden wurde, was sich auch in den Kopplungsdichte widerspiegelte. Die immobilisierten Enzyme wurden in Bezug auf Aktivität, Wiederverwendbarkeit, Lagerfähigkeit und Temperaturstabilität untersucht. Beide Varianten zeigten vergleichbare Leistungen, wobei tsT bei höheren Temperaturen eine etwas bessere Stabilität aufwies. Für den Antikörperverdau wurden sowohl thermische als auch chemische Denaturierungen bei verschiedenen Temperaturen ( 37 °C und 60 °C) getestet. Die Analyse mit MALDI-TOF-MS zeigte, dass gute Werte für die Sequenzabdeckung erzielt werden konnten. Besonders die chemische Denaturierung führte zu besseren Ergebnissen mit weniger Selbstverdau. Beim Vergleich mit kommerziell immobilisiertem Crude-Trypsin zeigten die rekombinanten Varianten eine höhere Spezifität und bessere Sequenzabdeckung bei gleichzeitig geringerem Selbstverdau. Die Wiederverwendbarkeit wurde durch fünf Verdauzyklen bei 37 °C überprüft. Dabei blieb die Aktivität weitgehend stabil, auch wenn die Peakintensität in den MALDI-Spektren mit jedem Zyklus abnahm. Eine eindeutige Zuordnung der Fingerprints des Antikörpers aus einer Bibliothek von über 90 Antikörpern war trotz dessen gegeben. KW - Korund KW - Immobilisierung KW - Proteomik KW - Rekombinante Proteine KW - Thermostabile Enzyme PY - 2025 SP - 1 EP - 86 CY - Berlin AN - OPUS4-64433 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Béalu, Zoé A1 - Walther, Johanna A1 - Abusafia, Attaallah A1 - Altmann, Korinna A1 - Meurer, Maren A1 - Gretzschel, Oliver A1 - Schäfer, Michael A1 - Steinmetz, Heidrun T1 - Removal of Organic Micropollutants and Microplastics via Ozonation Followed by Granular Activated Carbon Filtration N2 - Discharge from Wastewater Treatment Plants (WWTPs) can result in the emission of organic micropollutants (OMPs) and microplastics (MPs) into the aquatic environment. To prevent this harmful release, a pilot plant consisting of an ozonation followed by a granular activated carbon (GAC) filter was operated at a WWTP in Germany, and its side-effects on the concentrations of nitrogen (N) and phosphorous (P) compounds were measured. Over 80% of OMPs and transformation products were removed during the operating time (around 6000 bed volumes) no matter the ozone dose (from around 0.1 to 0.5 mgO3/mgDOC), except for Diatrizoic acid, whose breakthrough appeared at 3500 BV. Formation of the oxidation by-product, NDMA, increased with higher ozone doses, but the concentration remained below 100 ng/L. Bromate was formed at a higher ozone dose (0.4 mgO3/mgDOC) but at a low concentration—below 10 µg/L. The MP particles detected in the inflow (PE, SBR, PP, and PS) were effectively eliminated to a high degree, with a removal rate of at least 92%. Carbon parameters (COD, DOC, and SAC254) were removed further by the pilot plant, but to different extents. As expected, nitrate was formed during ozonation, while nitrite’s concentration decreased. Further, nitrite decreased and nitrate increased within the GAC filter, while ammonium was eliminated by at least 90%. Total P concentration decreased after the pilot, but the concentration of PO4-P increased. KW - Microplastics KW - TED-GC/MS KW - Granular Activated Carbon Filtration KW - Removal of Organic Micropollutants KW - Wastewater treatment plant PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615209 DO - https://doi.org/10.3390/environments11110241 VL - 11 IS - 11 SP - 1 EP - 38 PB - MDPI AG AN - OPUS4-61520 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fadda, Marta A1 - Sacco, Alessio A1 - Altmann, Korinna A1 - Ciornii, Dmitri A1 - Milczewski, Frank A1 - Bañares, Miguel A. A1 - Portela, Raquel A1 - Giovannozzi, Andrea Mario A1 - Rossi, Andrea Mario T1 - Tracking nanoplastics in drinking water: a new frontier with the combination of dielectrophoresis and Raman spectroscopy N2 - Detection of micro- (MPs) and nanoplastics (NPs) in food and environmental matrices has been gaining relevance due to their potential toxicological effects on human health. While MPs have been detected in a wide range of complex matrices, suitable methods for the characterization and chemical identification of NPs are still lacking, primarily due to significant methodological challenges associated with their nano-specific physiochemical properties, including size distribution (1 nm – 1 µm), dynamic surface chemical changes, and carbon-based composition, which complicate their detection compared to engineered nanomaterials. To overcome the traditional limitations of spectroscopic techniques in terms of spatial resolution and sensitivity at the sub-micrometer level, a novel label-free methodology is presented for specifically identifying the chemical composition of NPs directly in suspension by combining Raman spectroscopy with dielectrophoresis (DEP). Using a custom-built device, small volumes of NPs are injected into a dielectrophoretic cell and locally trapped by DEP forces to fill the Raman confocal volume, facilitating their detection and identification, and providing high signal-to-noise ratio Raman spectra for more reliable analysis. This approach was successfully applied to both Milli-Q water and a commercial brand of drinking water, enabling the rapid identification of various types of NPs with different sizes and polymer compositions at concentrations as low as 20 µg/mL. These included certified reference polystyrene beads ranging from 800 to 60 nm in diameter, as well as polydisperse NPs, more representative of real samples in terms of size distribution and polymer type, such as polyethylene (450 nm), polypropylene (180 nm), and polyethylene terephthalate (100 nm). Moreover, the chemical fingerprint of each NPs was thoroughly investigated and compared with the corresponding bulk polymers, highlighting possible changes in the Raman bands due to surface oxidation or nanometer-scale effect. Therefore, this innovative method can be considered a valuable approach for addressing gaps in the detection and identification of NPs, as well as for monitoring their dynamic phisiochemical changes in real matrices. KW - Nanoplastics KW - Water contaminants KW - Raman microspectroscopy KW - Dielectrophoresis PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-633658 DO - https://doi.org/10.1186/s43591-025-00131-y SN - 2662-4966 VL - 5 IS - 1 SP - 1 EP - 11 PB - Springer Science and Business Media LLC AN - OPUS4-63365 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fünning, Tabea A1 - Peczek, Anna A1 - Kroh, Aleksandra A1 - Mai, Christian A1 - Paul, Martin A1 - Thomsen, Florian A1 - Tannenberg, Robert A1 - Schumann, Christoph A1 - Weller, Michael G. A1 - Mai, Andreas A1 - Steglich, Patrick C. ED - Lieberman, Robert A. ED - Baldini, Francesco ED - Homola, Jiri T1 - Optimization of local backside released micro-ring resonators for sensing applications using silicon photonic integrated circuits in a SOI technology N2 - Photonic micro-ring resonators (MRR) are widely studied for their high sensitivity across applications like environmental monitoring, healthcare, and chemical analysis. Their evanescent field sensing requires partially unembedded waveguides compatible with CMOS processing. Our approach uses local backside etching with an additional buried oxide (BOX) etch to release waveguides while preserving the back-end of line (BEOL) structure, enabling spatial separation of the sensing area and electronics. The BOX etch critically affects sensor performance, as waveguide surface roughness can alter MRR properties and coupling. We analyzed MRR design variations, comparing wet and dry etching techniques for their effects on optical performance across rib and strip waveguides in quasi-TE and quasi-TM modes. Wafer-level measurements show that backside-released MRR achieve high extinction ratios with slightly reduced quality factors, advancing high-sensitivity photonic sensors. T2 - SPIE Optics + Optoelectronics 2025 CY - Prague, Czech Republic DA - 23.05.2025 KW - Photonic sensors KW - Micro-ring resonator (MRR) KW - Silicon on insulator (SOI) KW - CMOS KW - Local backside etching PY - 2025 SN - 978-1-5106-8851-3 DO - https://doi.org/10.1117/12.3056481 VL - 13527 SP - 1 EP - 8 PB - SPIE CY - Bellingham, WA , USA AN - OPUS4-63585 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Steglich, Patrick A1 - Paul, Martin A1 - Fünning, Tabea A1 - Schumann, Christoph A1 - Mai, Christian A1 - Tannenberg, Robert A1 - Mai, Andreas ED - Cheben, Pavel ED - Čtyroký, Jiří ED - Molina-Fernández, Iñigo T1 - Towards monolithic integration of polymer-based electro-optical devices in silicon photonic integrated circuits using a 250nm SOI technology N2 - Photonic micro-ring resonators (MRR) are widely studied for their high sensitivity across applications like environmental monitoring, healthcare, and chemical analysis. Their evanescent field sensing requires partially unembedded waveguides compatible with CMOS processing. Our approach uses local backside etching with an additional buried oxide (BOX) etch to release waveguides while preserving the back-end of line (BEOL) structure, enabling spatial separation of the sensing area and electronics. The BOX etch critically affects sensor performance, as waveguide surface roughness can alter MRR properties and coupling. We analyzed MRR design variations, comparing wet and dry etching techniques for their effects on optical performance across rib and strip waveguides in quasi-TE and quasi-TM modes. Wafer-level measurements show that backside-released MRR achieve high extinction ratios with slightly reduced quality factors, advancing high-sensitivity photonic sensors. T2 - SPIE Optics + Optoelectronics 2025 CY - Prague, Czech Republic DA - 05.06.2025 KW - Photonic sensors KW - Micro-ring resonator (MRR) KW - Silicon on insulator (SOI) KW - CMOS KW - Local backside etching (LBE) PY - 2025 DO - https://doi.org/10.1117/12.3056280 VL - 13530 SP - 1 EP - 8 PB - SPIE CY - Bellingham, WA , USA AN - OPUS4-63587 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cakir, Cafer Tufan T1 - Algorithm-Assisted Multimodal Synchrotron Experiments: XRD–XES Integration and SpecTwin N2 - Multimodal synchrotron-based techniques are emerging as powerful tools for advanced materials characterization, enabling simultaneous insights into both crystal and electronic structure. We present a combined X-ray diffraction (XRD) and high-resolution X-ray emission spectroscopy (XES) approach implemented in a double-dispersive setup. This configuration enables simultaneous acquisition of structural and spectroscopic information with high precision, allowing us to resolve correlations between lattice arrangements and electronic configurations under in situ conditions. To enhance experimental throughput and reproducibility, we employ digital twin concepts and optimization algorithms for experiment design and parameter control. These methods effectively eliminate trial-and-error procedures when optimizing the setup to achieve the desired resolution for XES analysis. In addition, we introduce SpecTwin, a dedicated software environment that integrates XES data analysis, simulation, and optimization routines. This combined methodology underscores the potential of algorithm-assisted multimodal X-ray experiments to advance the quantitative understanding of structure–property relationships in complex materials. T2 - Joint BAM-HZB Symposium on Multimodal Synchrotron Experiments for Next-Generation Materials Research CY - Berlin, Germany DA - 25.02.2026 KW - XAS KW - Digital Twin KW - Optimization KW - Multimodal PY - 2026 AN - OPUS4-65608 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumann, Christoph T1 - Design and optimization of integrated multimode interferometers (MMIs) for dual-polarization photonic biosensors for biomedical applications in a silicon-on-insulator platform N2 - Faster, more sensitive, and cost-efficient diagnostic tests are crucial, as conventional lab tests are slow and expensive, while rapid tests often lack specificity. Advancements in medical diagnostics are crucial for early disease detection, reducing costs and testing time. Optical biosensors, particularly multimode interferometers (MMIs), offer high sensitivity and integration potential for Point-of-Care applications [1-2]. This work introduces a novel MMI biosensor utilizing orthogonal TE and TM modes, significantly minimizing the footprint. T2 - SPIE Optics + Optoelectronics 2025 CY - Prague, Czech Republic DA - 23.05.2025 KW - Interferometry KW - Semiconductor KW - Chip KW - Point-of-Care applications KW - Biomarker PY - 2025 UR - https://www.spiedigitallibrary.org/conference-proceedings-of-spie/PC13527/PC135270R/Design-and-optimization-of-integrated-multimode-interferometers-MMIs-for-dual/10.1117/12.3056490.short DO - https://doi.org/10.1117/12.3056490 AN - OPUS4-63568 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Döring, Sarah T1 - Surface Immobilization of Recombinant Trypsin onto Corundum Particles for Optimized Antibody Digestion N2 - Therapeutic monoclonal antibodies are the fastest-growing class of biological agents and the development of reliable analytical methods for their quantification is becoming increasingly important. Liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) represents one of the leading technologies for antibody quantification. The serin protease trypsin has emerged as the gold standard enzyme for digesting intact protein into peptides for this approach. However, many protocols exist that often lead to different results depending on the digestion procedure. In particular, the type and amounts of detergents added during sample preparation for protein unfolding before digestion is known to create undesirable structure modifications of proteins (e.g. carbamylation) and significant bias in measurement results by inhibiting enzyme activity. The source and nature of the enzyme itself can also have an influence, whereby immobilized variants are increasingly being used to improve their stability, minimize self-digestion and enable a higher substrate-enzyme ratio. Here, we explored the potential of a novel thermostable trypsin and surface-functionalised corundum particles for enhanced antibody digestion. For this purpose, the inactive zymogen was recombinantly produced in E. coli, activated with enterokinase digestion and finally affinity purified by benzamidine purification. The enzyme activity was analogous to commercially available MS-grade trypsin product. In addition, produced trypsin showed increased thermal stability under typical digestion conditions compared to reference product. Furthermore, APTES-silanization followed by glutaraldehyde modification of corundum surface with an additional blocking step prevents nonspecific protein adsorption during the protein digestion procedure and the immobilized enzyme still showed substrate activity after covalent binding. Compared to wild-type and a non-immobilized enzyme, the surface-functionalized thermostable variant showed increased activity at elevated temperatures. Thus, this novel type of trypsin particles promises to not only improve antibody digestion at high temperatures, but also to prevent self-digestion and enable the separation of trypsin from target peptides in LC–MS analysis. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - Antibody Quantification KW - Corundum KW - Enzyme Immobilization KW - LC-MS/MS PY - 2025 AN - OPUS4-63480 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tannenberg, Robert T1 - Troponin I Assay in Wafer-Level Backside Optofluidics N2 - Cardiovascular diseases are the number one cause of death worldwide and responsible for 17.9 million casualities worldwide in 2019. Cardiac Troponin I (cTnI) is the most important biomarker for acute events such as heart attacks. The development of novel photonic integrated microchips (PIC) is a promising approach to allow the convenient detection of key biomarkers in complex matrices through multichannel real-time analysis in a highly compact package. This study presents the development and proof-of-concept of a backside released CMOS chip designed for the multichannel real-time detection of biomarkers. In this work, we introduce a Troponin I assay as well that utilizes a potential and practical approach to backside optofluidics on a wafer-level platform. T2 - Biosensors 2025 - 35th Anniversary World Congress on Biosensors CY - Lisbon, Portugal DA - 19.05.2025 KW - Ring resonator KW - Semiconductor KW - CMOS KW - cTnI KW - Heart attack KW - Biomarker KW - Sandwich immunoassay PY - 2025 AN - OPUS4-63481 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tannenberg, Robert T1 - Multichannel real-time detection of biomarkers with highly miniaturized photonic microchips N2 - The development of novel photonic microchips is a promising approach to advance the detection of biomarkers through multichannel real-time analysis. This study reports the successful development of a backside released CMOS chip designed for the multichannel real-time detection of biomarkers. Operating at a wavelength of 1550 nm, the microchip features three detection channels in addition to a reference channel, enabling simultaneous analysis of multiple biomarkers. The microchip incorporates micro-ring resonators that are directly functionalized with specific bioreceptors, which significantly improves the affinity towards target biomarkers. The employed surface functionalization strategy enables versatile immobilization of receptor molecules and serves as a starting point for various analytical applications. A tunable laser is utilized as the excitation source, providing precise wavelength tuning and stable optical output, essential for achieving optimal resonance conditions within the micro-ring resonators. Our chips use integrated multi-mode interferometers as beam-splitter, grating coupler and Ge-photodiodes, resulting in an ultra-small footprint. The complete chip including metal pads has an area of 1 mm2. The results indicate that the developed multichannel photonic microchip system enables online detection of multiple biomarkers. The compact and highly miniaturized design of this microchip positions them as promising candidates for point-of-care diagnostics and personalized medicine applications. With further advancements, this technology opens a path to transform biomarker detection across various medical fields, offering rapid, reliable, and cost-effective diagnostic solutions. In conclusion, the presented multichannel photonic microchips signify a substantial leap forward in real-time biomarker detection, providing a robust platform for future research and clinical applications. T2 - SPIE Optics + Optoelectronics 2025 CY - Prague, Czech Republic DA - 07.04.2025 KW - Biosensor KW - Optics KW - Silicon semiconductor KW - Proteins KW - Clinical chemistry PY - 2025 AN - OPUS4-62954 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Döring, Sarah T1 - Optimization of Polymer Interface: Novel Surface-functionalized Corundum Particles for Improved Antibody Digestion N2 - Therapeutic monoclonal antibodies are the fastest-growing class of biological agents and the development of reliable analytical methods for their quantification is becoming increasingly important. Liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) represents one of the leading technologies for antibody quantification. The serin protease trypsin has emerged as the gold standard enzyme for digesting intact protein into peptides for this approach. However, many protocols exist that often lead to different results. The talk will provide a brief introduction to the application of novel thermostable and surface-functionalized trypsin particles for improved antibody digestion as well as initial successes in polymer functionalization of the corundum surface to prevent nonspecific protein adsorption during the digestion procedure. T2 - SALSA Make and Measure 2024: Interfaces CY - Berlin, Germany DA - 11.09.2024 KW - Antibody Quantification KW - Recombinant Enzymes KW - LC-MS/MS KW - Enzyme Immobilisation KW - Surface Functionalisation KW - Corundum PY - 2024 AN - OPUS4-61041 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Döring, Sarah T1 - Sequence of Mus Musculus monoclonal IgG2c anti-CCMV Immunoglobulin N2 - We report the full-length nucleotide and amino acid sequences of the light (κ) and heavy chain of the IgG2c anti-CCMV monoclonal antibody (hybridoma clone BAM-CCMV-29-81), generated against Cowpea Chlorotic Mottle Virus (CCMV). Sequencing of hybridoma clone was performed using a cost-effective Sanger-based workflow that includes DNA-level subclass determination and peptide mass fingerprint confirmation. The κ-chain sequence was assigned to IGKV4-6101 / IGKJ101, while the heavy chain was assigned to IGHV2-601 / IGHD1-101 / IGHJ3*01 with IgG2c constant regions from the NOD strain. Both chains were validated against RNA Illumina sequencing, confirming 100% identity. The sequences are available in GenBank under accession numbers PX123807 (κ-chain) and PX123808 (heavy chain). KW - Antibody Sequencing KW - BAM-CCMV-29-81 KW - anti-CCMV-antibody PY - 2025 UR - https://www.ncbi.nlm.nih.gov/nuccore/PX123807 UR - https://www.ncbi.nlm.nih.gov/nuccore/PX123808 PB - National Library of Medicine CY - Bethesda AN - OPUS4-63968 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Fischer, Janina A1 - Kaufmann, Jan Ole A1 - Weller, Michael G. T1 - Simple Determination of Affinity Constants of Antibodies by Competitive Immunoassays N2 - The affinity constant, also known as the equilibrium constant, binding constant, equilibrium association constant, or the reciprocal value, the equilibrium dissociation constant (Kd), can be considered as one of the most important characteristics for any antibody-antigen pair. Many methods based on different technologies have been proposed and used to determine this value. However, since a very large number of publications and commercial datasheets do not include this nformation, significant obstacles in performing such measurements seem to exist. In other cases where such data are reported, the results have often proved to be unreliable. This situation may indicate that most of the technologies available today require a high level of expertise that does not seem to be available in many laboratories. In this paper, we present a simple approach based on standard immunoassay technology that is easy and quick to perform. It relies on the effect that the molar IC50 approaches the Kd value in the case of infinitely small concentrations of the reagent concentrations. A two-dimensional dilution of the reagents leads to an asymptotic convergence to Kd. The approach has some similarity to the well-known checkerboard titration used for the optimization of immunoassays. A well-known antibody against the FLAG peptide, clone M2, was used as a model system and the results were compared with other methods. This approach could be used in any case where a competitive assay is available or can be developed. The determination of an affinity constant should belong to the crucial parameters in any quality control of antibody-related products and assays and should be mandatory in papers using immunochemical protocols. N2 - Die Affinitätskonstante, auch bekannt als Gleichgewichtskonstante, Bindungskonstante, Gleichgewichtsassoziationskonstante oder der Kehrwert, die Gleichgewichtsdissoziationskonstante (Kd), kann als eine der wichtigsten Eigenschaften für jedes Antikörper-Antigen-Paar angesehen werden. Es wurden viele Methoden auf der Grundlage verschiedener Technologien vorgeschlagen und verwendet, um diesen Wert zu bestimmen. Da jedoch eine sehr große Anzahl von Veröffentlichungen und kommerziellen Datenblättern diese Informationen nicht enthalten, scheint es erhebliche Hindernisse bei der Durchführung solcher Messungen zu geben. In anderen Fällen, in denen solche Daten angegeben werden, haben sich die Ergebnisse oft als unzuverlässig erwiesen. Diese Situation könnte darauf hindeuten, dass die meisten der heute verfügbaren Technologien ein hohes Maß an Fachwissen erfordern, das in vielen Laboren nicht vorhanden zu sein scheint. In diesem Artikel stellen wir einen einfachen Ansatz vor, der auf der Standard-Immunoassay-Technologie basiert und einfach und schnell durchzuführen ist. Er beruht auf dem Effekt, dass sich der molare IC50-Wert dem Kd-Wert im Fall unendlich kleiner Konzentrationen der Reagenzienkonzentrationen nähert. Eine zweidimensionale Verdünnung der Reagenzien führt zu einer asymptotischen Konvergenz zu Kd. Der Ansatz weist eine gewisse Ähnlichkeit mit der bekannten Schachbrett-Titration auf, die zur Optimierung von Immunoassays verwendet wird. Ein bekannter Antikörper gegen das FLAG-Peptid, Klon M2, wurde als Modellsystem verwendet und die Ergebnisse wurden mit anderen Methoden verglichen. Dieser Ansatz kann in allen Fällen verwendet werden, in denen ein kompetitiver Test verfügbar ist oder entwickelt werden kann. Die Bestimmung einer Affinitätskonstante sollte zu den entscheidenden Parametern in jeder Qualitätskontrolle von Antikörper-bezogenen Produkten und Tests gehören und in Veröffentlichungen, die immunchemische Protokolle verwenden, obligatorisch sein. KW - ELISA KW - Microplate KW - Microtiter plate KW - IC50 KW - Test midpoint KW - Competitive immunoassay KW - Law of mass action KW - Thermodynamics KW - Equilibrium constant KW - SPR KW - Surface plasmon resonance KW - Clones KW - Interaction KW - kd value KW - ITC KW - MST PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621298 DO - https://doi.org/10.20944/preprints202404.0996.v1 SN - 2310-287X SP - 1 EP - 11 PB - MDPI CY - Basel AN - OPUS4-62129 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bartczak, Dorota A1 - Sikora, Aneta A1 - Goenaga-Infante, Heidi A1 - Altmann, Korinna A1 - Drexel, Roland A1 - Meier, Florian A1 - Alasonati, Enrica A1 - Lelong, Marc A1 - Cado, Florence A1 - Chivas-Joly, Carine A1 - Fadda, Marta A1 - Sacco, Alessio A1 - Rossi, Andrea Mario A1 - Pröfrock, Daniel A1 - Wippermann, Dominik A1 - Barbero, Francesco A1 - Fenoglio, Ivana A1 - Booth, Andy M. A1 - Sørensen, Lisbet A1 - Igartua, Amaia A1 - Wouters, Charlotte A1 - Mast, Jan A1 - Barbaresi, Marta A1 - Rossi, Francesca A1 - Piergiovanni, Maurizio A1 - Mattarozzi, Monica A1 - Careri, Maria A1 - Caebergs, Thierry A1 - Piette, Anne-Sophie A1 - Parot, Jeremie A1 - Giovannozzi, Andrea Mario T1 - Multiparameter characterisation of a nano-polypropylene representative test material with fractionation, light scattering, high-resolution microscopy, spectroscopy, and spectrometry methods N2 - Reference and quality control materials with comparable physicochemical properties to nanoplastic contaminants present in environmental and food nanoplastics are currently lacking. Here we report a nanoplastic polypropylene material prepared using a top-down approach involving mechanical fragmentation of larger plastics. The material was found to be homogeneous and stable in suspension and has been characterised for average particle size, size distribution range, particle number concentration, polypropylene mass fraction and inorganic impurity Content using a wide range of analytical methods, including AF4, cFFF, PTA, (MA)DLS, MALS, SEM, AFM, TEM, STEM, EDS,Raman, ICP-MS and pyGC-MS. The material was found to have a broad size distribution, ranging from 50 nm to over 200 nm, with the average particle size value dependent on the technique used to determine it. Particle number concentration ranged from 1.7–2.4 × 1010 g−1 , according to PTA. Spectroscopy techniques confirmed that the material was polypropylene, with evidence of aging due to an increased level of oxidation. The measured mass fraction was found to depend on the marker used and ranged between 3 and 5 μg g−1 . Inorganic impurities such as Si, Al, Mg, K, Na, S, Fe, Cl and Ca were also identified at ng g−1 levels. Comparability and complementarity across the measurement methods and techniques is also discussed. KW - Polypropylene KW - Nanoplastics KW - Analytics KW - Reference material KW - Scattering methods PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654680 DO - https://doi.org/10.1039/D5EN00917K SN - 2051-8153 SP - 1 EP - 15 PB - Royal Society of Chemistry (RSC) AN - OPUS4-65468 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Backes, A. T. A1 - Reinmuth-Selzle, K. A1 - Leifke, A. L. A1 - Ziegler, K. A1 - Krevert, C. S. A1 - Tscheuschner, Georg A1 - Lucas, K. A1 - Weller, Michael G. A1 - Berkemeier, T. A1 - Pöschl, U. A1 - Fröhlich-Nowoisky, J. T1 - Oligomerization and Nitration of the Grass Pollen Allergen Phl p 5 by Ozone, Nitrogen Dioxide, and Peroxynitrite: Reaction Products, Kinetics, and Health Effects N2 - The allergenic and inflammatory potential of proteins can be enhanced by chemical modification upon exposure to atmospheric or physiological oxidants. The molecular mechanisms and kinetics of such modifications, however, have not yet been fully resolved. We investigated the oligomerization and nitration of the grass pollen allergen Phl p 5 by ozone (O3), nitrogen dioxide (NO2), and peroxynitrite (ONOO–). Within several hours of exposure to atmospherically relevant concentration levels of O3 and NO2, up to 50% of Phl p 5 were converted into protein oligomers, likely by formation of dityrosine cross-links. Assuming that tyrosine residues are the preferential site of nitration, up to 10% of the 12 tyrosine residues per protein monomer were nitrated. For the reaction with peroxynitrite, the largest oligomer mass fractions (up to 50%) were found for equimolar concentrations of peroxynitrite over tyrosine residues. With excess peroxynitrite, the nitration degrees increased up to 40% whereas the oligomer mass fractions decreased to 20%. Our results suggest that protein oligomerization and nitration are competing processes, which is consistent with a two-step mechanism involving a reactive oxygen intermediate (ROI), as observed for other proteins. The modified proteins can promote pro-inflammatory cellular signaling that may contribute to chronic inflammation and allergies in response to air pollution. KW - Protein KW - Nitrotyrosine KW - Dityrosine KW - Allergy KW - Hay fever KW - Diesel exhaust KW - Combustion KW - Exhaust PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529729 DO - https://doi.org/10.3390/ijms22147616 VL - 22 IS - 14 PB - MDPI CY - Basel AN - OPUS4-52972 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -