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 U6 - 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 - JOUR A1 - Schwarz, G. A1 - Beck, S. A1 - Weller, Michael G. A1 - Linscheid, M.W. T1 - Comparison of the fragmentation behavior of differentially metal-coded affinity tag (MeCAT)-labeled peptides PY - 2012 U6 - https://doi.org/10.1002/jms.3036 SN - 1076-5174 SN - 1096-9888 VL - 47 IS - 7 SP - 885 EP - 889 PB - Wiley CY - Chichester AN - OPUS4-27436 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steglich, P. A1 - Rabus, D. G. A1 - Sada, C. A1 - Paul, Martin A1 - Weller, Michael G. A1 - Mai, C. A1 - Mai, A. T1 - Silicon Photonic Micro-Ring Resonators for Chemical and Biological Sensing: A Tutorial N2 - Silicon photonic micro-ring resonators (MRR) developed on the silicon-on-insulator (SOI) platform, owing to their high sensitivity and small footprint, show great potential for many chemical and biological sensing applications such as label-free detection in environmental monitoring, biomedical engineering, and food analysis. In this tutorial,we provide the theoretical background and give design guidelines for SOI-based MRR as well as examples of surface functionalization procedures for label-free detection of molecules. After introducing the advantages and perspectives of MRR, fundamentals of MRR are described in detail, followed by an introduction to the fabrication methods, which are based on a complementary metal-oxide semiconductor (CMOS) technology. Optimization of MRR for chemical and biological sensing is provided, with special emphasis on the optimization of waveguide geometry. At this point, the difference between chemical bulk sensing and label-free surface sensing is explained, and definitions like waveguide sensitivity, ring sensitivity, overall sensitivity as well as the limit of detection (LoD) of MRR are introduced. Further, we show and explain chemical bulk sensing of sodium chloride (NaCl) in water and provide a recipe for label-free surface sensing. KW - Biosensors KW - Biophotonics KW - Chemosensor KW - Biosensor KW - Microresonator KW - Nanophotonics KW - Optical sensors KW - Photonic sensors KW - Optoelectronic KW - Ring resonator KW - Silicon photonics KW - Miniaturization KW - Lab-on-a-chip KW - Lab-on-chip KW - Waveguide KW - Surface chemistry KW - Silanization KW - Glutaraldehyde KW - Affinity immobilization KW - Antibody KW - Oriented immobilization KW - Real-time measurement PY - 2022 U6 - https://doi.org/10.1109/JSEN.2021.3119547 SN - 1530-437X VL - 22 IS - 11 SP - 10089 EP - 10105 PB - IEEE AN - OPUS4-55147 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tscheuschner, Georg A1 - Kaiser, Melanie N. A1 - Lisec, Jan A1 - Beslic, D. A1 - Muth, Thilo A1 - Krüger, M. A1 - Mages, H. W. A1 - Dorner, B. G. A1 - Knospe, J. A1 - Schenk, J. A. A1 - Sellrie, F. A1 - Weller, Michael G. T1 - MALDI-TOF-MS-Based Identification of Monoclonal Murine Anti-SARS-CoV-2 Antibodies within One Hour N2 - During the SARS-CoV-2 pandemic, many virus-binding monoclonal antibodies have been developed for clinical and diagnostic purposes. This underlines the importance of antibodies as universal bioanalytical reagents. However, little attention is given to the reproducibility crisis that scientific studies are still facing to date. In a recent study, not even half of all research antibodies mentioned in publications could be identified at all. This should spark more efforts in the search for practical solutions for the traceability of antibodies. For this purpose, we used 35 monoclonal antibodies against SARS-CoV-2 to demonstrate how sequence-independent antibody identification can be achieved by simple means applied to the protein. First, we examined the intact and light chain masses of the antibodies relative to the reference material NIST-mAb 8671. Already half of the antibodies could be identified based solely on these two parameters. In addition, we developed two complementary peptide mass fingerprinting methods with MALDI-TOF-MS that can be performed in 60 min and had a combined sequence coverage of over 80%. One method is based on the partial acidic hydrolysis of the protein by 5 mM of sulfuric acid at 99 degrees C. Furthermore, we established a fast way for a tryptic digest without an alkylation step. We were able to show that the distinction of clones is possible simply by a brief visual comparison of the mass spectra. In this work, two clones originating from the same immunization gave the same fingerprints. Later, a hybridoma sequencing confirmed the sequence identity of these sister clones. In order to automate the spectral comparison for larger libraries of antibodies, we developed the online software ABID 2.0. This open-source software determines the number of matching peptides in the fingerprint spectra. We propose that publications and other documents critically relying on monoclonal antibodies with unknown amino acid sequences should include at least one antibody fingerprint. By fingerprinting an antibody in question, its identity can be confirmed by comparison with a library spectrum at any time and context. KW - Reproducibility KW - Quality control KW - Traceability KW - Peptides KW - Peptide mass fingerprinting KW - Monoclonal antibody KW - Recombinant antibody KW - Identity KW - Antibody identification KW - Sequencing KW - Light chain KW - Mass spectrometry KW - Software KW - Open science KW - Library KW - COVID-19 KW - Corona virus KW - Sequence coverage KW - NIST-mAb 8671 KW - Reference material KW - RBD KW - Spike protein KW - Nucleocapsid KW - Cleavage KW - Tryptic digest KW - MALDI KW - DHAP KW - 2,5-dihydroxyacetophenone KW - Github KW - Zenodo KW - ABID PY - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-547347 VL - 11 IS - 2 SP - 1 EP - 22 PB - MDPI CY - Basel AN - OPUS4-54734 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Juds, Carmen A1 - Schmidt, J. A1 - Weller, Michael G. A1 - Lange, Thorid A1 - Beck, Uwe A1 - Conrad, T. A1 - Boerner, H. G. T1 - Combining phage display and next-generation sequencing for materials sciences: A case study on probing polypropylene surfaces N2 - Phage display biopanning with Illumina next-generation sequencing (NGS) is applied to reveal insights into peptide-based adhesion domains for polypropylene (PP). One biopanning round followed by NGS selects robust PP-binding peptides that are not evident by Sanger sequencing. NGS provides a significant statistical base that enables motif analysis, statistics on positional residue depletion/enrichment, and data analysis to suppress false-positive sequences from amplification bias. The selected sequences are employed as water-based primers for PP-metal adhesion to condition PP surfaces and increase adhesive strength by 100% relative to nonprimed PP. KW - Polymers KW - Polypropylene KW - Glue KW - Plastics KW - Surface Activation KW - Primer KW - Peptide Library KW - Epoxy KW - Solid-binding Peptides KW - Functionalization KW - Polymer-binding Peptides KW - Adhesion KW - Material-binding Peptides KW - Adhesives PY - 2020 U6 - https://doi.org/10.1021/jacs.0c03482 SN - 0002-7863 SN - 1520-5126 VL - 142 IS - 24 SP - 10624 EP - 10628 PB - ACS CY - Washington, DC, USA AN - OPUS4-51123 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Celasun, S. A1 - Remmler, D. A1 - Schwaar, Timm A1 - Weller, Michael G. A1 - Du Prez, F. A1 - Börner, H. G. T1 - Digging into the sequential space of thiolactone precision polymers: A combinatorial strategy to identify functional domains N2 - Functional sequences of precision polymers based on thiolactone/Michael chemistry are identified from a large one-bead one-compound library. Single-bead readout by MALDI-TOF MS/MS identifies sequences that host m-THPC that is a second Generation photo-sensitizer drug. The corresponding Tla/Michael-PEG conjugates make m-THPC available in solution and drug payload as well as drug release kinetics can be fine-tuned by the precision segment. KW - Combinatorial chemistry KW - Combinatorial polymer libraries KW - Sequence-defined oligomer KW - Precision polymer sequencing KW - Pseudo peptides KW - MALDI-TOF KW - ESI MS KW - Mass spectrometry KW - Sequencing KW - PEG KW - Polyethylene glycol KW - Solubilizer KW - Drug KW - Conjugates PY - 2019 U6 - https://doi.org/10.1002/anie.201810393 SN - 1521-3773 VL - 58 IS - 7 SP - 1960 EP - 1964 PB - Wiley-VCH CY - Weinheim AN - OPUS4-47323 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwaar, Timm A1 - Lettow, Maike A1 - Remmler, Dario A1 - Börner, H. G. A1 - Weller, Michael G. T1 - Efficient Screening of Combinatorial Peptide Libraries by Spatially Ordered Beads Immobilized on Conventional Glass Slides N2 - Screening of one-bead-one-compound (OBOC) libraries is a proven procedure 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 traditional peptide screening involves tedious steps such as affinity selection, bead picking, sequencing, and characterization. Herein, we present a high-throughput “all-on-one chip” system to avoid slow and technically complex bead picking steps. On a traditional glass slide provided with an electrically conductive tape, beads of a combinatorial peptide library are aligned and immobilized by application of a precision sieve. Subsequently, the chip is 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, high-affinity binders are directly and unambiguously sequenced with high accuracy without picking of the positive beads. The use of an optimized ladder sequencing approach improved the accuracy of the de-novo sequencing step to nearly 100%. The new technique was validated by employing a FLAG-based model system, identifying new peptide binders for the monoclonal M2 anti-FLAG antibody, and was finally utilized to search for IgG-binding peptides. In the present format, more than 30,000 beads can be screened on one slide. KW - Peptide library KW - HTS KW - Target KW - MALDI KW - Mass spectrometry KW - Biochip KW - Lab-on-a-Chip KW - Array KW - Screening KW - Ladder sequencing KW - Binder KW - Pharmaceutical PY - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-478973 UR - https://www.mdpi.com/2571-5135/8/2/11 VL - 8 IS - 2 SP - 1 EP - 15 PB - MDPI CY - Basel AN - OPUS4-47897 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bahlmann, Arnold A1 - Carvalho, José Joao A1 - Weller, Michael G. A1 - Panne, Ulrich A1 - Schneider, Rudolf T1 - Immunoassays as high-throughput tools: monitoring spatial and temporal variations of carbamazepine, caffeine and cetirizine in surface and wastewaters N2 - Carbamazepine (CBZ), caffeine and cetirizine were monitored by enzyme-linked immunosorbent assays (ELISAs) in surface and wastewaters from Berlin, Germany. This fast and cost-efficient method enabled to assess the spatial and temporal variation of these anthropogenic markers in a high-throughput screening. CBZ and cetirizine were detected by the same antibody, which selectively discriminates between both compounds depending on the pH value used in the incubation step. To our best knowledge, this is the first dual-analyte immunoassay working with a single antibody. The frequent sampling with 487 samples being processed allowed for the repeated detection of unusually high concentrations of CBZ and caffeine. ELISA results correlate well with the ones obtained by liquid chromatography tandem mass spectrometry (LC-MS/MS). Caffeine concentrations found in surface waters were elevated by combined sewer overflows after stormwater events. During the hay fever season, the concentrations of the antihistamine drug cetirizine increased in both surface and wastewaters. Caffeine was almost completely removed during wastewater treatment, while CBZ and cetirizine were found to be more persistent. The maximum concentrations of caffeine, CBZ and cetirizine found in influent wastewater by LC–MS/MS were 470, 5.0 and 0.49 µg L-1, while in effluent wastewater the concentrations were 0.22, 4.5 and 0.51 µg L-1, respectively. For surface waters, concentrations up to 3.3, 4.5 and 0.72 µg L-1 were found, respectively. KW - ELISA KW - Carbamazepine KW - Caffeine KW - Cetirizine KW - Environmental monitoring KW - Anthropogenic markers PY - 2012 U6 - https://doi.org/10.1016/j.chemosphere.2012.05.020 SN - 0045-6535 SN - 0366-7111 VL - 89 IS - 11 SP - 1278 EP - 1286 PB - Elsevier Science CY - Kidlington, Oxford AN - OPUS4-26187 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Carvalho, José Joao A1 - Walter, Astrid A1 - Baermann, Yvonne A1 - Weller, Michael G. A1 - Panne, Ulrich A1 - Schenk, J.A. A1 - Schneider, Rudolf T1 - Non-invasive monitoring of immunization progress in mice via IgG from feces N2 - A non-invasive method to monitor the humoral immune response in mice after immunization is described. From fecal pellets of an individual mouse, a sufficient amount of active immunoglobulins or their fragments can be extracted to perform a regular examination of the status of the immune response by immunoassay. Hapten-specific antibodies from the feces of mice from three immunization trials showed very similar characteristics to those obtained from serum at a given date. Therefore, it can be suspected that some serum IgG enters the intestinal lumen and ends up in the feces, where they appear to be considerably stable. Hapten-specific IgAs were not found in the feces. Being able to analyze antibody titers in feces could be an interesting animal welfare refinement to standard practice that does not entail repeated blood sampling. KW - Immunization monitoring KW - IgG KW - Coproantibodies KW - Feces KW - Animal welfare KW - 3R concept PY - 2012 UR - http://iv.iiarjournals.org/content/26/1/63.full.pdf+html SN - 0258-851x VL - 26 IS - 1 SP - 63 EP - 70 PB - In vivo CY - Athens AN - OPUS4-25283 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weller, Michael G. T1 - A unifying review of bioassay-guided fractionation, effect-directed analysis and related techniques N2 - The success of modern methods in analytical chemistry sometimes obscures the problem that the ever increasing amount of analytical data does not necessarily give more insight of practical relevance. As alternative approaches, toxicity- and bioactivity-based assays can deliver valuable information about biological effects of complex materials in humans, other species or even ecosystems. However, the observed effects often cannot be clearly assigned to specific chemical compounds. In these cases, the establishment of an unambiguous cause-effect relationship is not possible. Effect-directed analysis tries to interconnect instrumental analytical techniques with a biological/biochemical entity, which identifies or isolates substances of biological relevance. Successful application has been demonstrated in many fields, either as proof-of-principle studies or even for complex samples. This review discusses the different approaches, advantages and limitations and finally shows some practical examples. The broad emergence of effect-directed analytical concepts might lead to a true paradigm shift in analytical chemistry, away from ever growing lists of chemical compounds. The connection of biological effects with the identification and quantification of molecular entities leads to relevant answers to many real life questions. KW - Toxicity KW - Drug discovery KW - Natural products KW - Environmental analysis KW - Lead identification PY - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-262960 SN - 1424-8220 VL - 12 IS - 7 SP - 9181 EP - 9209 PB - MDPI CY - Basel AN - OPUS4-26296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -