TY - JOUR A1 - Martínez, N.A. A1 - Schneider, Rudolf A1 - Messina, G.A. A1 - Raba, J. T1 - Modified paramagnetic beads in a microfluidic system for the determination of ethinylestradiol (EE2) in river water samples N2 - In this work, we have developed and characterized a novel microfluidic immunoassay methodology for rapid and sensitive quantification of ethinylestradiol (EE2) in river water samples. The detection of EE2 was carried out using a competitive direct immunoassay method based on the use of anti-EE2 polyclonal antibodies immobilized on magnetic microspheres 3-aminopropyl-modified manipulated for an external removable magnet. The EE2 present in the water sample was allowed to compete with EE2-horseradish peroxidase (HPR) conjugated for the immobilized anti-EE2 antibody. The HPR, in the presence of hydrogen peroxide (H2O2) catalyzes the oxidation of catechol (Q) whose back electrochemical reduction was detected on gold electrode at 0.0 V. The response current obtained from the product of enzymatic reaction is inversely proportional to the amount of EE2 in the water sample. The electrochemical detection can be done within 1 min and total assay time was 30 min. The calculated detection limits for electrochemical detection and the ELISA procedure are 0.09 and 0.32 ng L-1 respectively and the intra- and inter-assay coefficients of variation were below 5.8%. Our electrochemical immunosensor showed higher sensitivity and lower time consumed than the standard spectrophotometric detection ELISA method, which shows the potential for assessment of EE2 in river water samples. KW - Enzyme immunoassays KW - Ethinylestradiol KW - Paramagnetic beads KW - Horseradish peroxidase KW - Microfluidic KW - Flow injection analysis PY - 2010 DO - https://doi.org/10.1016/j.bios.2009.10.031 SN - 0956-5663 SN - 1873-4235 VL - 25 IS - 6 SP - 1376 EP - 1381 PB - Elsevier CY - Barking, Essex, UK AN - OPUS4-22188 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lima, D.L.D. A1 - Silva, C.P. A1 - Schneider, Rudolf A1 - Esteves, V.I. T1 - Development of an ELISA procedure to study sorption of atrazine onto a sewage sludge-amended luvisol soil N2 - Pesticides may contaminate ground and surface waters and one of the major factors governing this property is soil sorption. Sorption can be assessed by batch equilibrium technique which produces lots of extracts with high dissolved organic carbon concentration in which the pesticide concentration has to be determined. We developed an ELISA procedure to analyse atrazine based on polyclonal antibodies (C193) for which tracer structure and dilutions of immunochemical reagents were adapted to fit the purpose. After a 1000-fold dilution (or after an SPE clean-up procedure) extracts of a sewage-sludge amended luvisol (used as an example application of the methodology developed) could be reliably analysed. The Freundlich model is able to describe adsorption for this system (r² = 0.977) delivering a distribution coefficient KF of 1.6 ± 0.2 (mg kg-1) (mg L-1)-N and an isotherm nonlinearity factor N of 0.70 ± 0.09. KW - ELISA KW - Atrazine KW - Sorption PY - 2011 DO - https://doi.org/10.1016/j.talanta.2011.06.024 SN - 0039-9140 VL - 85 IS - 3 SP - 1494 EP - 1499 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-24305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Calisto, V. A1 - Bahlmann, Arnold A1 - Schneider, Rudolf A1 - Esteves, V.I. T1 - Application of an ELISA to the quantification of carbamazepine in ground, surface and wastewaters and validation with LC-MS/MS N2 - Carbamazepine is a psychiatric pharmaceutical widely detected in aquatic environments. Due to its generalized occurrence and environmental persistence it might be considered as an anthropogenic pollution indicator. In this research, a previously developed enzyme-linked immunosorbent assay (ELISA), based on a commercial monoclonal antibody, was applied to the quantification of carbamazepine in ground, surface and wastewaters and results were validated by liquid chromatography–tandem mass spectrometry (LC–MS/MS). The performance of the applied ELISA methodology was tested in the presence of high concentrations of sodium chloride and dissolved organic matter. The method was not significantly affected by matrix effects, being adequate for the quantification of carbamazepine in environmental samples, even without sample pre-treatment. This method allows the quantification of carbamazepine in the range of 0.03–10 µg L-1, with a relative error lower than 30%. Due to a pH dependent cross-reactivity with cetirizine, an antihistaminic drug, the assay also enabled the quantification of cetirizine in the samples. The application of the developed method to the quantification of carbamazepine was performed by using environmental samples with very different matrices, collected in the geographical area of Ria de Aveiro, an estuarine system located in the North of Portugal. Carbamazepine was detected in all analyzed wastewater samples and in one surface water with concentrations between 0.1 and 0.7 µg L-1. Validation with LC–MS/MS revealed that results obtained by ELISA are 2–28% overestimated, which was considered highly satisfactory due to the absence of sample pre-treatments. KW - Immunoassay KW - Pharmaceuticals KW - Environment KW - Wastewater treatment plants KW - Matrix effects KW - Cetirizine PY - 2011 DO - https://doi.org/10.1016/j.chemosphere.2011.04.072 SN - 0045-6535 SN - 0366-7111 VL - 84 IS - 11 SP - 1708 EP - 1715 PB - Elsevier Science CY - Kidlington, Oxford AN - OPUS4-24306 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Immunoanalytical Methods for the Environmental Sciences T2 - Vortrag im Rahmen des Schwerpunktes "CITE - Chemicals In The Environment" CY - Leipzig, Germany DA - 2011-12-02 PY - 2011 AN - OPUS4-24947 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Entwicklung und Validierung von Immunoassays unterschiedlicher Formate T2 - zmdb-Workshop "Trends in Bioanalysis" CY - Wildau, Germany DA - 2011-05-26 PY - 2011 AN - OPUS4-24940 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Uncertainty in Measurement with Immunoassays T2 - EURACHEM/CITAC-Workshop: Recent Development in Measurement Uncertainty CY - Lisbon, Portugal DA - 2011-06-07 PY - 2011 AN - OPUS4-24941 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Identification of unknown contaminants and metabolites of pharmaceuticals in waste water by HR-MS analysis of chromatographic fractions pre-selected by ELISA T2 - 7th Annual LC/MS/MS Workshop on Environmental Applications and Food Safety CY - Buffalo, NY, USA DA - 2011-06-13 PY - 2011 AN - OPUS4-24942 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - LC-ELISA coupling for structure elucidation of transformation products of pharmaceuticals in surface water T2 - EmCon 2011 CY - Copenhagen, Denmark DA - 2011-08-25 PY - 2011 AN - OPUS4-24943 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Pharmazeutika im Abwasser- und Trinkwasserkreislauf T2 - GDCh Wissenschaftsforum Chemie 2011 CY - Bremen, Germany DA - 2011-09-06 PY - 2011 AN - OPUS4-24944 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Non-target Analysis of Emerging Contaminants by LC-ELISA and HR-MS T2 - ICCE 2011 - EuCheMS International Conference on Chemistry and the Environment CY - Zurich, Switzerland DA - 2011-09-12 PY - 2011 AN - OPUS4-24945 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Carvalho, José Joao A1 - Schneider, Rudolf ED - Preedy, V.R. T1 - Analysis of caffeine by immunoassay KW - Immunoassay KW - ELISA KW - Koffein KW - Getränke KW - Trinkwasser KW - Oberflächengewässer KW - Abwasser KW - Speichel PY - 2012 SN - 978-1-84973-367-0 SN - 2045-1695 N1 - Serientitel: Food and nutritional components in focus – Series title: Food and nutritional components in focus VL - 2 IS - Chapter 12 SP - 213 EP - 229 PB - RSC Publ. AN - OPUS4-26530 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Non-target analysis of emerging contaminants - harnessing antibody selectivity T2 - SETAC 2012 (6th SETAC World Congress and SETAC Europe 22nd Annual Meeting) CY - Berlin, Germany DA - 2012-05-20 PY - 2012 N1 - Geburtsname von Hoffmann, Kristin: Petsch, K. - Birth name of Hoffmann, Kristin: Petsch, K. AN - OPUS4-26648 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Vorkommen und Abbauverhalten von Carbamazepin und seinen Metaboliten in Abwasser, Oberflächenwasser und Trinkwasser T2 - GDch/SETAC: Erkennen, Untersuchen, Modellieren - Vom Nutzen des Verstehens; Gemeinsame Jahrestagung von SETAC GLB (German Language Branch) und fachgruppe Umweltchemie und Ökotoxikologie der GDCh CY - Leipzig, Germany DA - 2012-09-10 PY - 2012 AN - OPUS4-26651 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Application of an optimized ELISA assay in the assessment of 17?-estradiol levels in surface and waste waters from the Aveiro region T2 - 3rd Portuduese Young Chemists Meeting (3PYCheM) CY - Oporto, Portugal DA - 2012-11-09 PY - 2012 AN - OPUS4-26652 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Identification of Non-Target Analytes by LC-ELISAbFollowed by Accurate Mass Spectromentry T2 - PittCon 2012 CY - Orlando, FL, USA DA - 2012-03-11 PY - 2012 AN - OPUS4-26645 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, Rudolf T1 - LC-ELISA uncovers cetirizine - Pharmaceuticals in the environment N2 - A large number of pharmacologically active compounds have been detected in the aquatic environment during the last decade [1] and this gives rise to many concerns [2]. The substances have been disclosed by accident, clever search or elaborate mass spectrometry. Nowadays a broad spectrum of drug parent compounds can be screened for [3], yet the knowledge about the presence of isomers and transformation products (metabolites, conjugates, degradates) is still limited. KW - Immunoassay KW - ELISA KW - Carbamazepin KW - Cetrizin KW - Pharmazeutika KW - Abwasser KW - Oberflächengewässer PY - 2011 SN - 1434-2634 VL - 5-6 SP - 16 EP - 18 PB - GIT Verl. CY - Darmstadt AN - OPUS4-26565 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Immunoassays für das Monitoring von pharmakologisch wirksamen Stoffen im Wasserkreislauf bis hin zum Trinkwasser T2 - Trends und Perspektiven in der Lebensmittel- und Umweltanalytik CY - Potsdam, Germany DA - 2012-10-24 PY - 2012 AN - OPUS4-26836 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Albumin and monoclonal antibody conjugated porphyrin: synthesis, characterization and biological potential against human bladder cancer cell line T2 - 3rd National Meeting on Medicinal Chemistry of the Portuguese Chemical Society SPQ CY - Aveiro, Portugal DA - 2012-11-28 PY - 2012 AN - OPUS4-27469 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Environment Protection with Innovative Cavitation Technologies - Degradation of 17a-Ethynyl Estradiol by Hydrodynamic-Accoustic-Cavitation T2 - International Conference of Environment 2012 (ICENV) - Green Technology for Sustainable Tomorrow CY - Penang, Malaysia DA - 2012-12-11 PY - 2012 AN - OPUS4-27470 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Degradation of carbamazepine in environmentally relevant concentrations in water by Hydrodynamic-Acoustic-Cavitation (HAC) T2 - 3rd International Conference on Sustainable Pharmacy CY - Osnabrück, Germany DA - 2012-11-19 PY - 2012 AN - OPUS4-27471 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Immunanalytik für umweltchemische Fragestellung T2 - VDI Institutskolloquium des Instituts für Technische Chemie und Umweltchemie CY - Jena, Germany DA - 2013-01-29 PY - 2013 AN - OPUS4-27813 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Silva, C.P. A1 - Lima, D.L.D. A1 - Schneider, Rudolf A1 - Otero, M. A1 - Esteves, V.I. T1 - Development of ELISA methodologies for the direct determination of 17beta-estradiol and 17alpha-ethinylestraydiol in complex aqueous matrices N2 - This study comprises the development of enzyme-linked immunosorbent assays (ELISAs) for the quantification of 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) in complex aqueous matrices without any sample clean-up procedures. Salinity and dissolved organic matter were selected as potential interfering agents in the analysis of E2 and EE2. The optimization was performed in order to (i) overcome matrix effects, and to (ii) increase sensitivity. The addition of a sample buffer containing bovine serum albumin (BSA) prior to the sample was found to decrease the influence of matrix effects. Moreover, adjustments of this buffer's pH together with the optimization of tracer (T) dilution and incubation time were undertaken in order to lower the quantification range. The optimized methods allowed the quantification of E2 and EE2 in the ranges 0.03–200 µg L-1 and 0.02–10 µg L-1, respectively. The assays were applied to real aqueous samples. It was possible to do a first approach to the levels of E2 in Portuguese surface and waste waters; however, it was not feasible to detect EE2 in the samples tested. KW - Enzyme-linked immunosorbent assay KW - Endocrine disrupting compounds KW - 17beta-Estradiol KW - 17alpha-Ethinylestradiol KW - Surface water KW - Wastewater PY - 2013 DO - https://doi.org/10.1016/j.jenvman.2013.03.041 SN - 0301-4797 SN - 1095-8630 VL - 124 SP - 121 EP - 127 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-28516 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ecke, Alexander A1 - Bell, Jérémy A1 - Schneider, Rudolf T1 - A three-dimensional microfluidic flow cell and system integration for improved electrochemical substrate detection in HRP/TMB-based immunoassays N2 - Immunoassays, based on the recognition and capture of analytes by highly selective antibodies, are now used extensively in all areas of diagnostics, but the challenge is to further integrate them into online sensors. To improve the transition from laboratory immunoassays to immunosensors, we have developed a complete flow system, based on a microfluidic core flow cell to enable automated detection of one of the most commonly used immunoassay substrates, TMB, by chronoamperometry. The architecture and fluidic optimisation of the system showed that a specially designed 3D flow cell allows higher flow rates (500 μL min−1) than a standard enlarged microfluidic channel (50 μL min−1) resulting in a significantly shorter detection time of 30 seconds per sample and making the system more robust against interferences due to bubble formation in the chip. The electrochemical measurements showed an improved signal-to-noise ratio (SNR) and thus higher sensitivity for a model immunoassay for diclofenac (SNR = 59), compared to the analytical performance of a conventional laboratory microplate-based assay with optical detection (SNR = 19). In general, this system facilitates the conversion of any conventional immunoassay into an immunosensor with automatic and continuous detection. KW - Microfluidic KW - Immunoassay KW - Electrochemical KW - Mikrofluidik KW - Immunassay KW - Elektrochemie PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580159 DO - https://doi.org/10.1039/d3sd00095h VL - 2 SP - 887 EP - 892 PB - Royal Society of Chemistry CY - London, United Kingdom AN - OPUS4-58015 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Electrochemical immunosensing with a 3-dimensional microfluidic flow cell N2 - Immunoassays, based on analyte recognition and capture by highly selective antibodies with high affinity, are intensively used in all fields of laboratory diagnostics and in screen-ings of food and environmental samples. Yet, for many purposes, online sensors are desir-able, and, in principle, all immunoassay tech-niques can be integrated into lab-on-chip set-ups that can work as continuous monitoring devices. Yet, the challenge remains to devel-op platforms and elements that are fit for a quick transition of laboratory microplate as-says to immunosensors. T2 - European Biosensor Symposium CY - Aachen, Germany DA - 28.08.2023 KW - Biosensor KW - Antibodies KW - Microfluidics KW - Electrochemical detection PY - 2023 AN - OPUS4-59240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Electrochemical immunosensing with a 3-dimensional microfluidic cell N2 - The flash presentation give a quick overview of the work performed. T2 - European Biosensor Symposium CY - Aachen, Germany DA - 28.08.2023 KW - Biosensors KW - microfluidics KW - antibodies KW - Electrochemical detection PY - 2023 AN - OPUS4-59202 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Certified Reference Materials by BAM - Status and Perspectives T2 - ANALYTICA CY - Shanghai, China DA - 2008-09-23 PY - 2008 AN - OPUS4-18053 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf A1 - Konthur, Zoltán T1 - Bestimmung von anthropogenen Markerkonzentrationen im Abwasser mittels eines antikörperbasierten Verfahrens (ELISA) N2 - Im Rahmen des AMELAG Projektes wurden im Auftrag des Umweltbundesamtes (VH1804) unterschiedliche anthropogene Marker in Abwasserproben aus Brandenburg und Mecklenburg-Vorpommern gemessen. In dieser Präsentation wurden einige Ergebnisse vorgestellt. T2 - AMELAG Abschlussveranstaltung am Robort-Koch-Institut CY - Berlin, Germany DA - 13.12.2024 KW - Östron KW - Koffein KW - Carbamazepin KW - Clarithromycin PY - 2024 AN - OPUS4-62194 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Spurenstoffe im Rohabwasser: Möglichkeiten und Perspektiven für den One-Health-Ansatz N2 - Der One-Health-Ansatz hat die Gesundheit von Mensch, Tier und Umwelt im Fokus. Dazu ist eine interdisziplinäre Zusammenarbeit von Akteuren aus Human- und Veterinärmedizin sowie den Umweltwissenschaften notwendig. Ein Ineinandergreifen von methodischen Ansätzen und der Analytik wird angestrebt. Im Zuge der anstehenden Novellierung (2924) der EU-Kommunalabwasserrichtlinie (91/271/EWG) wird die Umsetzung eines One-Health-Ansatzes bereits adressiert. Dazu gehört zum einen der Ausbau und die Prozessüberwachung einer vierten Reinigungsstufe in Klärwerken. Zum anderen ist europaweit die Infrastruktur einer Abwassersurveillance zur Überwachung von Krankheitserregern zu gewährleisten. Dies wird aktuell in Deutschland mit dem Projekt AMELAG ("Abwassermonitoring zur epidemiologischen Lagebewertung") mit zwei Probennahmen pro Woche auf ca. 170 Kläranlagen umgesetzt. T2 - 6. Mülheimer Wasseranalytisches Seminar (MWAS 2024) CY - Mülheim an der Ruhr, Germany DA - 10.09.2024 KW - ELISA KW - Spurenstoffe KW - Koffein KW - Carbamazepin KW - Diclofenac KW - Immunoassay PY - 2024 AN - OPUS4-60993 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ecke, Alexander A1 - Bell, Jérémy A1 - Schneider, Rudolf T1 - From Laboratory Immunoassays to Immunosensors with an Integrated Microfluidic Flow System N2 - This research summary describe efforts to the development of a three-dimensional microfluidic flow cell for improved electrochemical substrate detection in HRP/TMB-based immunoassays. This work provides a valuable advancement in the sensitivity and integration of immunoassay technologies, aiding in the refinement of diagnostic tools. KW - Antikörper KW - Immunoassay KW - Microfluidics KW - Electrochemical detection KW - Biosensor PY - 2025 UR - https://www.elveflow.com/microfluidics-research-summaries/from-laboratory-immunoassays-to-immunosensors-with-an-integrated-microfluidic-flow-system/ SP - 1 EP - 4 CY - Paris AN - OPUS4-62674 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf A1 - Konthur, Zoltán A1 - Jaeger, Carsten T1 - Reference Material (IgG) for CCQM-PAWG Key Comparison N2 - BAM proposes a recombinant human IgG (anti-tetanus monoclonal antibody SA13) as candidate material for the 2027 CCQM-PAWG key comparison on antibody purity. The antibody is produced via hybridoma and recombinant expression systems, with detailed sequence and glycosylation profiling. Analytical methods include MALDI-TOF-MS, SEC, DLS, and UV-vis spectroscopy to assess purity, aggregation, and stability. Preliminary results show high purity, low heterogeneity, and consistent size distribution. A minimum of 40 mg IgG is required, with 100 mg preferred for deeper characterization. Production is expected to be completed by the end of 2026, with potential for a joint technical project. T2 - Spring Meeting of CCQM-PAWG CY - Sèvres, France DA - 06.04.2025 KW - Antibodies KW - Research Grade Test Material KW - Mass spectrometry KW - Affinity PY - 2025 AN - OPUS4-63503 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abdelshafi, Nahla A. A1 - Bell, Jérémy A1 - Rurack, Knut A1 - Schneider, Rudolf T1 - Microfluidic electrochemical immunosensor for the trace analysis of cocaine in water and body fluids N2 - Quick but accurate testing and on‐the‐spot monitoring of cocaine in oral fluids and urine continues to be an important toxicological issue. In terms of drug testing, a number of devices have been introduced into the market in recent decades, notably for workplace inspection or roadside testing. However, these systems do not always fulfill the requirements in terms of reliability, especially when low cut‐off levels are required. With respect to surface water, the presence of anthropogenic small organic molecules such as prescription and over‐the‐counter pharmaceuticals as well as illicit drugs like cannabinoids, heroin, or cocaine, has become a challenge for scientists to develop new analytical tools for screening and on‐site analysis because many of them serve as markers for anthropogenic input and consumer behavior. Here, a modular approach for the detection of cocaine is presented, integrating an electrochemical enzyme‐linked immunosorbent assay (ELISA) performed on antibody‐grafted magnetic beads in a hybrid microfluidic sensor utilizing flexible tubing, static chip and screen‐printed electrode (SPE) elements for incubation, recognition, and cyclic voltammetry measurements. A linear response of the sensor vs. the logarithm of cocaine concentration was obtained with a limit of detection of 0.15 ng/L. Within an overall assay time of 25 minutes, concentrations down to 1 ng/L could be reliably determined in water, oral fluids, and urine, the system possessing a dynamic working range up to 1 mg/L. KW - Cocaine PY - 2018 DO - https://doi.org/10.1002/dta.2515 VL - 11 SP - 492 EP - 500 PB - Wiley CY - Weinheim AN - OPUS4-48319 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Monitoring trace substances in wastewater and surface water by immunoanalytical assays and sensors N2 - Monitoring the elimination of trace substances in wastewater treatment plants, as required in the recast of the EU Urban Wastewater Treatment Directive and the new Kommunalabwasserrichtlinie (KARL), creates a need for on-site analyses in wastewater treatment plants. Immunoanalytical methods can be carried out on site, e.g. in the form of rapid tests, but continuously operating (immuno-bio)sensors would be ideal. And antibody-based methods have the inherent disadvantage that one antibody must be used per analyte and therefore only a small number of substances can be analysed. A set of indicators has been integrated in the directives in accordance with the list of the Kompetenzzentrum Spurenstoffe BW (KomS) and offer points of reference here. Yet, in order to be able to use immunoanalytical methods for their monitoring, (DIN/ISO) standards are required that define the necessary quality requirements and quality management measures for the sensors. In addition, for the larger part of the indicators, the required antibodies have yet to be developed and made commercially available in the long term. The talk will highlight our previous work on high-throughput methods, such as ELISA, regarding the presence of anthropogenic markers and some indicators as well as research approaches for sensor technology that could be used on-site, and will provide an overview of deficits and future efforts. T2 - Kolloquium der Abteilung Technische Umweltchemie und Sensortechnik CY - Stuttgart, Germany DA - 21.05.2025 KW - Antibodies KW - Immunoassay KW - Microfluidics KW - Biosensor KW - Trace substances PY - 2025 AN - OPUS4-63501 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Bestimmung von Spurenstoffen im (Roh-)Abwasser mittels ELISA N2 - Der Vortrag behandelt die Bestimmung von Spurenstoffen im Rohabwasser mithilfe von ELISA (Enzyme-Linked Immunosorbent Assay), einer immunanalytischen Methode, die sich durch hohe Sensitivität und Eignung für Hochdurchsatzanalysen auszeichnet. Im Rahmen der Projekte MARKERIA I & II wurden verschiedene anthropogene Marker wie Koffein, Carbamazepin, Diclofenac, Bisphenol A und Hormone wie Östron untersucht, um deren Eignung für die Abwassersurveillance zu bewerten. Die Ergebnisse zeigen, dass einige Substanzen wie Carbamazepin stabile Konzentrationen aufweisen und sich gut als Marker eignen, während andere wie Koffein starke Schwankungen zeigen. Einige Marker wie Isolithocholsäure werden zwar in hohen Konzentrationen gefunden, zeigen aber methodische Herausforderungen wie instabile Assays. Die Studie hebt hervor, dass es Hotspots mit erhöhten Konzentrationen gibt, aber insgesamt eine relativ geringe Variabilität zwischen verschiedenen Rohabwässern besteht. Zukünftige Entwicklungen sollen sich auf die Verbesserung von Antikörpern, die Entwicklung tragbarer Vor-Ort-Analysemethoden und die Standardisierung immunanalytischer Verfahren konzentrieren. T2 - AMELAG-Colloquium "Spurenstoffe im (Ab-)Wasser" CY - Online meeting DA - 20.06.2025 KW - Antikörper KW - Schnelltests KW - Abwasser KW - ELISA PY - 2025 AN - OPUS4-63500 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hoffmann, Holger A1 - Knizia, Christian A1 - Kuhne, Maren A1 - Panne, Ulrich A1 - Schneider, Rudolf T1 - LC–ELISA as a contribution to the assessment of matrix effects with environmental water samples in an immunoassay for estrone (E1) N2 - Estrone (E1), a metabolite of the estrogenic hormones 17β-estradiol (β-E2) and 17α-estradiol (α-E2), is itself a potent estrogen which can have a significant impact on the hormonal balance. Due to ist high potential for adverse effects on human health and aquatic life even at pg/L to ng/L levels, its appearance in water should be monitored. E1 has also been considered a marker substance for the presence of other estrogens. This study presents a newly developed direct competitive enzymelinked immunosorbent assay (ELISA) for quantification of E1 in environmental water samples using new monoclonal antibodies. The quantification range of the ELISA is 0.15 μg/L to 8.7 μg/L E1, and the limit of detection is around 60 ng/L for not pre-concentrated water samples. A pre-concentration step after careful selection of suitable phases for SPE was developed, too. The influence of organic solvents and natural organic matter on the ELISA was assessed. The high selectivity of the monoclonal antibody was demonstrated by determining the cross-reactivity against 20 structurally related compounds. For the assessment of matrix effects, a concept (“LC–ELISA”) is thoroughly exploited, i.e., separating complex samples by HPLC into 0.3 min fractions and determination of the apparent E1 concentration. Furthermore, fractions with interferences for nontarget/suspected-target analysis can be assigned. A dilution approach was applied to distinguish between specific interferences (cross-reactants) and non-specific interferences (matrix effects). In the determination of 18 environmental samples, a good agreement of the E1 concentration in the respective fractions was obtained with mean recoveries of 103 % to 132 % comparing ELISA to LC–MS/MS. KW - Validierung KW - Immunoassay KW - Matrixeffekte KW - Abwasser KW - Oberflächenwasser KW - ELISA KW - LC-MS/MS KW - Hormone KW - Endokrine Disruptoren PY - 2018 DO - https://doi.org/10.1007/s00769-018-1351-7 SN - 1432-0517 SN - 0949-1775 VL - 23 IS - 6 SP - 349 EP - 364 PB - Springer CY - Heidelberg AN - OPUS4-46891 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abdelshafi, Nahla A. A1 - Panne, Ulrich A1 - Schneider, Rudolf T1 - Screening for cocaine on Euro banknotes by a highly sensitive enzyme immunoassay N2 - This study focused on quantitative detection of cocaine on Euro banknotes in Germany. A sensitive direct competitive immunoassay was developed and optimized with a limit of detection (LOD) of 5.6 ng/L. Exhaustive cocaine extraction by solvent was tested using different methanol concentrations and buffered solutions. Crossreactivity studies were performed to determine the degree of interference of cocaine metabolites with the immunoassay. Sixty-five Euro banknotes obtained from different districts in Berlin were evaluated. A 100% contamination frequency with cocaine was detected. A comparison between the amount of cocaine extracted by cotton swabbing of one square centimeter of the banknote showed a good correlation for lower contamination levels. This assay showed high sensitivity of detecting pg of cocaine per 1 cm2 of one banknote by swabbing 1 cm2: 0, 14, and 21 pg/cm2. Moreover, three notes of different denominations revealed high cocaine concentration; 1.1 mg/note, and twice 55 μg/note. KW - Cocaine KW - Euro banknotes KW - Drugs on bills KW - Enzyme-Linked Immunosorbent Assay KW - ELISA PY - 2017 DO - https://doi.org/10.1016/j.talanta.2017.01.004 SN - 0039-9140 SN - 1873-3573 VL - 165 SP - 619 EP - 624 PB - Elsevier AN - OPUS4-39150 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schneider, Rudolf T1 - Wasserdiagnose durch die Verwendung von Markern N2 - Die Überwachung des gesamten Wasserkreislaufs auf Mikroverunreinigungen ist aus gesundheitlicher und ökologischer Hinsicht wünschenswert und gewinnt durch den Klimawandel und das zunehmende Erfordernis der Wiederverwendung des Brauchwassers weiter an Bedeutung. Die schnellen und kostengünstigen antikörperbasierten Methoden („Immunoassays“) können helfen, Informationslücken zu schließen und kürzere Reaktionszeiten zu ermöglichen. Von Labormethoden über tragbare Analysengeräte bis hin zu Online-Sensoren sind viele Formate möglich (u. a. ELISA, Abb. 1). Es muss zudem die Bereitstellung der notwendigen, hochqualitativen Antikörper gewährleistet werden. Da aber gilt „1 Analyt – 1 Antikörper“, ist die Herstellung eines Konsenses bezüglich der vordringlich zu bestimmenden Indikatoren/Marker notwendig. Auch die Normung der Verfahren ist parallel in Angriff zu nehmen. KW - Antikörper KW - Immunoassay KW - Abwasser KW - ELISA PY - 2025 UR - https://analyticalscience.wiley.com/content/article-do/wasserdiagnose-durch-die-verwendung-von-markern VL - 2025 IS - 1 SP - 1 EP - 4 PB - WILEY CY - Hoboken, NJ, USA AN - OPUS4-63508 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Keeping the Y N2 - The talk traces my career path and presents BAM as an attractive employer. It also offers advice on shaping one's own career after PhD. T2 - IWC Alumni Day 2025 CY - Garching bei München, Germany DA - 04.07.2025 KW - Antibodies KW - ELISA KW - Career PY - 2025 AN - OPUS4-63640 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Carl, Peter A1 - Schneider, Rudolf T1 - A wash-free, multiplex microbead assay for determination of emerging bioactive compounds in wastewater N2 - Pollutants of low molecular weight, such as drug residues, are in the focus of water quality assessment: some of them, like carbamazepine are only partially degraded in wastewater treatment plants. Thus, these pollutants can serve as marker substances for elimination efficiencies. Monitoring water quality demands for selective, high-throughput and multi-target analytical methods. Immunoassays, such as ELISA, offer the possibility to be highly sensitive and selective due to the specific recognition by high affinity of target molecules to antibodies (Abs). Batch-wise processing in microtiter plates allows for the necessary high-throughput, however only a single analyte can be determined within one measurement. To overcome these disadvantages, we developed a four-plex microbead-based flow cytometric assay, which is adaptable for the microtiter plate format. The modular and self-prepared bead support consists of polystyrene-core/silica-shell particles. While, the polystyrene core is used for encoding, by introducing different amounts of fluorescent dyes, the silica shell creates a solid support for the immunoassay: The target analytes, three drugs, carbamazepine, diclofenac and caffeine and the fecal marker isolithocholic acid are coupled covalently to the surface via NHS chemistry to amino groups on the surface. For determination of the pollutants, a mixture of specific Abs is incubated with the samples, to bind competitively on the “anchor” molecules on the surface of the beads or the analyte in solution. Bound antibodies are then visualized via fluorescent dye-labelled secondary Abs. Flow-cytometry allows for decoding of the beads and signal read-out, without washing the system. In order to decrease non-specific binding, we investigated different types of surface modifications, finding, that a PEG-based surface is suitable to support our immunoassay format. For maximum sensitivity, a design-of-experiment approach was chosen for optimization of the assay parameters. The resulting immunoassay is appropriate to quantify the pollutants in the low μg/L-range. T2 - EBS 2017 CY - Potsdam, Germany DA - 20.03.2017 KW - Immunoassay KW - Bead-based assay KW - Flow-cytometry PY - 2017 AN - OPUS4-39522 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Oberleitner, Lidia A1 - Grandke, Julia A1 - Mallwitz, F. A1 - Resch-Genger, Ute A1 - Garbe, L.-A. A1 - Schneider, Rudolf T1 - Fluorescence polarization immunoassays for the quantification of caffeine in beverages N2 - Homogeneous fluorescence polarization immunoassays (FPIAs) were developed and compared for the determination of caffeine in beverages and cosmetics. FPIAs were performed in cuvettes in a spectrometer for kinetic FP measurements as well as in microtiter plates (MTPs) on a multimode reader. Both FPIAs showed measurement ranges in the µg/L range and were performed within 2 and 20 min, respectively. For the application on real samples, high coefficients of variations (CVs) were observed for the performance in MTPs; the CVs for FPIAs in cuvettes were below 4%. The correlations between this method and reference methods were satisfying. The sensitivity was sufficient for all tested samples including decaffeinated coffee without preconcentration steps. The FPIA in cuvettes allows a fast, precise, and automated quantitative analysis of caffeine in consumer products, whereas FPIAs in MTPs are suitable for semiquantitative high-throughput screenings. Moreover, specific quality criteria for heterogeneous assays were applied to homogeneous immunoassays. KW - caffeine KW - Decaffeinated coffee KW - Fluorescence polarization immunoassay KW - Homogeneous immunoassay KW - Quality assurance criteria PY - 2014 DO - https://doi.org/10.1021/jf4053226 SN - 0021-8561 SN - 1520-5118 VL - 62 IS - 11 SP - 2337 EP - 2343 PB - American Chemical Society CY - Columbus, Ohio AN - OPUS4-30613 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grandke, Julia A1 - Oberleitner, Lidia A1 - Resch-Genger, Ute A1 - Garbe, L.-A. A1 - Schneider, Rudolf T1 - Quality assurance in immunoassay performance - carbamazepine immunoassay format evaluation and application on surface and waste water N2 - Carbamazepine (CBZ) is one of the most frequently detected pharmaceuticals in water samples. For the determination of this anthropogenic marker, various immunoassay formats were tested and evaluated in order to identify the most suitable one. For these direct competitive assays, the analyte was labelled with the enzyme horseradish peroxidase (HRP) or alkaline phosphatase (AP), and seven substrates with specific detection properties were used. The quality criteria for the standard curves were fulfilled by all HRP assays and the chemiluminescence AP format. Furthermore, intra- and inter-plate coefficients of variation as a measure of the achievable precision were determined for the samples. The application of the AP assays to surface water was unfeasible due to CBZ concentrations below the quantifiable concentration range. Surface as well as waste water samples could be analyzed with the HRP assays. Here, the HRP assay employing the chromogenic substrate 3,3',5,5'-tetramethylbenzidine yielded the best results. PY - 2013 DO - https://doi.org/10.1039/c3ay40702k SN - 1759-9660 SN - 1759-9679 VL - 5 IS - 15 SP - 3754 EP - 3760 PB - RSC Publ. CY - Cambridge AN - OPUS4-28860 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lima, D.L.D. A1 - Schneider, Rudolf A1 - Esteves, V.I. T1 - Development of an enzyme-linked immunosorbent assay for atrazine monitoring in water samples N2 - The implementation of the Water Framework Directive (2000/60/EC) requires the establishment of monitoring programs. However, conventional procedures for sample preparation prior to chromatographic analysis are rather expensive and time consuming, being the development of cost-effective and easy tool a necessity. The aim of this work was to develop an enzyme-linked immunosorbent assay (ELISA) able to determine atrazine in water samples. Matrix effects evaluation showed that the increase of humic acid (HA) concentration leads to flattened calibration curves and to the loss of the sigmoidal shape. However, such interference was overcome, by the presence of an environmental sample buffer, incubated together with the samples. Recoveries from 88.5 to 119.2 % were obtained in the presence of HA concentrations up to 20 mg-1. An analytical range from 0.003 to 1 µgL-1 was obtained, and atrazine was detected in a sewage treatment plant with concentrations ranging from 14 to 52 ngL-1. KW - Immunoassay KW - Atrazine KW - Surface waters KW - Wastewater treatment plants KW - Matrix effects PY - 2013 DO - https://doi.org/10.1007/s11356-012-1227-z SN - 0944-1344 SN - 1614-7499 VL - 20 IS - 5 SP - 3157 EP - 3164 PB - Ecomed Publ. CY - Landsberg AN - OPUS4-28299 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lima, D.L.D. A1 - Schneider, Rudolf A1 - Esteves, V.I. T1 - Sorption behavior of EE2 on soils subjected to different long-term organic amendments N2 - The transport and fate of hydrophobic organic contaminants in the environment involve complex phenomena that are influenced by many processes that include sorption by soil components. Sorption behavior of EE2 molecules onto different soil samples was studied and results correlated with the content and type of organic matter present. The highest Κ value, among all soils presented in this study, was obtained for soil fertilized with compost (1.22) which presented the highest organic carbon content. Also the sorption behavior depends greatly on the soil specific organic matter characteristics. A strong positive correlation was observed between aromatic and carboxylic units and ΚOC values. The results also suggested an association of the EE2 aromatic nuclei face to face with the surface and/or another EE2 molecule and also sorbent–sorbate interactions due to hydrogen or covalent bonding, likely to occur due to the presence of phenolic function at C-3 and hydroxyl function at C-17 of the EE2 molecules that can react with carboxylic functional groups of soil organic matter. The stronger EE2 sorbs to soil organic matter lower is the leaching into drinking water resources and runoff to rivers and surface water, minimizing its residual toxicity. KW - EE2 KW - Sorption KW - Soil KW - Deconvolution KW - Fluorescence PY - 2012 DO - https://doi.org/10.1016/j.scitotenv.2012.02.014 SN - 0048-9697 VL - 423 SP - 120 EP - 124 PB - Elsevier CY - Amsterdam AN - OPUS4-25739 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Martínez, N.A. A1 - Pereira, S.V. A1 - Bertolino, F.A. A1 - Schneider, Rudolf A1 - Messina, G.A. A1 - Raba, J. T1 - Electrochemical detection of a powerful estrogenic endocrine disruptor: ethylestradiol in water samples through bioseparation procedure N2 - The synthetic estrogen ethinylestradiol (EE2) is an active component of oral contraceptives (OCs), considered as an endocrine disrupting compound (EDC). It is excreted from humans and released via sewage treatment plant effluents into aquatic environments. EDCs are any environmental pollutant chemical that, once incorporated into an organism, affects the hormonal balance of various species including humans. Its presence in the environment is becoming of great importance in water quality. This paper describes the development of an accurate, sensitive and selective method for capture, preconcentration and determination of EE2 present in water samples using: magnetic particles (MPs) as bioaffinity support for the capture and preconcentration of EE2 and a glassy carbon electrode modified with multi-walled carbon nanotubes (MWCNTs/GCE) as detection system. The capture procedure was based on the principle of immunoaffinity, the EE2 being extracted from the sample using the anti-EE2 antibodies (anti-EE2 Ab) which were previously immobilized on MPs. Subsequently the analyte desorption was done employing a sulfuric acid solution and the determination of the EE2 in the pre-concentrated solution was carried out by square wave voltammetry (SWV). This method can be used to determine EE2 in the range of 0.035–70 ng L-1 with a detection limit (LOD) of 0.01 ng L-1 and R.S.D. < 4.20%. The proposed method has been successfully applied to the determination of EE2 in water samples and it has promising analytical applications for the direct determination of EE2 at trace levels. KW - Magnetic particles KW - Bioseparation KW - Ethinylestradiol KW - Electrochemistry KW - Immunoassay KW - Elektrochemischer Sensor KW - Endokrine Disruptoren KW - Hormone KW - EE2 KW - Östrogene PY - 2012 DO - https://doi.org/10.1016/j.aca.2012.02.033 SN - 0003-2670 SN - 1873-4324 SN - 0378-4304 VL - 723 SP - 27 EP - 32 PB - Elsevier CY - Amsterdam AN - OPUS4-25656 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Braeutigam, P. A1 - Franke, M. A1 - Schneider, Rudolf A1 - Lehmann, Andreas A1 - Stolle, A. A1 - Ondruschka, B. T1 - Degradation of carbamazepine in environmentally relevant concentrations in water by hydrodynamic-acoustic-cavitation (HAC) N2 - The antiepileptic drug carbamazepine is one of the most abundant pharmaceuticals in the German aquatic environment. The effect of low carbamazepine concentrations (1–50 µg L-1) is discussed controversially, but ecotoxicological studies revealed reproduction toxicity, decreased enzymatic activity and bioaccumulation in different test organisms. Therefore, as a preventive step, an efficient and cost-effective technique for wastewater treatment plants is needed to stop the entry of pharmaceuticals into the aquatic environment. Cavitation, the formation, growth, and subsequent collapse of gas- or vapor-filled bubbles in fluids, was applied to solve this problem. The technique of Hydrodynamic-Acoustic-Cavitation was used showing high synergistic effect. Under optimized conditions carbamazepine (5 µg L-1) was transformed by pseudo-first order kinetics to an extent of >96% within 15 min (27% by hydrodynamic cavitation, 33% by acoustic cavitation). A synergistic effect of 63% based on the sum of the single methods was calculated. Carbamazepine concentrations were monitored by a sensitive and selective immunoassay and after 60 min no known metabolites were detectable by LC-MS/MS. KW - Carbamazepine KW - Degradation KW - Hydrodynamic cavitation KW - Acoustic cavitation KW - ELISA PY - 2012 DO - https://doi.org/10.1016/j.watres.2012.02.013 SN - 0043-1354 VL - 46 IS - 7 SP - 2469 EP - 2477 PB - Elsevier CY - Amsterdam AN - OPUS4-25735 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Carvalho, J.J.D. A1 - Bahlmann, Arnold A1 - Schneider, Rudolf T1 - ELISA goes Berlin - Bestimmung von Carbamazepin, Cetrizin und Coffein in Berliner Gewässern N2 - Sensitive und selektive Immunoassays unterstützen Untersuchungen im Vollzug der EU Wasserrahmenrichtlinie. Sie erlauben, eine hohe Anzahl von Proben ohne Anreicherungsschritte zu untersuchen und ermöglichen daher den Aufbau eines zeitlich und räumlich engmaschigen Messnetzes. Mit Hilfe von ELISA (enzymelinked immunosorbent assay) wurde ein Gewässerscreening in Berlin durchgeführt. KW - ELISA KW - Koffein KW - Immunoassay KW - Oberflächenwasser KW - Wasseranalytik PY - 2012 SN - 0016-3538 VL - 4 SP - 278 EP - 281 PB - GIT-Verlag CY - Darmstadt AN - OPUS4-27518 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Carl, Peter A1 - Schneider, Rudolf T1 - Determination of pharmacologically active compounds in wastewater by a bead-based flow-cytometric immunoarray N2 - The assessment of water quality demands for multi-target compatible analytical methods. On the one hand, the influence of sewage on natural surface waters must be routinely monitored. On the other hand, estimation of removal efficiencies of pollutants, such as drug residues, is in the focus of industrial and public wastewater treatment. Immunoassays, such as ELISA, are often applied in this area, however, it is only possible to measure a single analyte in one measurement. In contrast, array technology is capable for measuring multiple substances in parallel. Here we present a four-plex bead-based flow cytometric assay for measuring three drugs (carbamazepine, an antiepileptic drug, diclofenac, an antiphlogistic and caffeine, a psychoactive substance) and the bile acid isolithocholic acid, which is proposed to be used as a fecal marker. In this suspension array core-shell particles, consisting of a polystyrene core and a silica shell, are used. They can be easily encoded with a fluorophore which is introduced to the core while the shell is functionalized with amino groups to which the analytes or their derivates are bound via NHS chemistry. They are the competitor binding sites for the antibodies. For the determination of the pollutants, the beads are incubated with a mixture of the analyte-specific antibodies. The molecules on the surface of the beads and the free analyte in solution compete for the binding sites of the antibodies. Bead-bound antibodies can then be visualized via dye-labelled secondary antibodies. For read-out a flow cytometer is used to virtually separate the differently encoded beads. In order to obtain highly selective binding of the antibodies, we investigated different types of surface modifications to overcome unspecific binding, finding that a PEG-based surface is suitable to support our immunoassay format. The resulting multiplexing assay is appropriate to detect the marker substances in the low µg/L range. T2 - Pittcon 2017 CY - Chicago, IL, USA DA - 05.03.2017 KW - Immunoassay KW - Bead-based assay KW - Flow-cytometry KW - Anthropogenic markers PY - 2017 AN - OPUS4-39524 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, Rudolf A1 - Grandke, Julia T1 - Temperatureinfluss auf Immunoassays N2 - Für Immunoassays ist die Temperatur ein wichtiger Parameter, denn sie beeinflusst Empfindlichkeit und Präzision des Tests. Niedrigere Temperaturen erhöhen die Nachweisempfindlichkeit, während bei Raumtemperatur das Messsignal am wenigsten schwankt. PY - 2012 SN - 1439-9598 SN - 1521-3854 VL - 60 IS - 11 SP - 1112 EP - 1113 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-26916 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abdelshafi, Nahla A. A1 - Bell, Jérémy A1 - Rurack, Knut A1 - Schneider, Rudolf T1 - Microfluidic electrochemical immunosensor for the trace analysis of cocaine in water and body fluids N2 - Quick but accurate testing and on‐the‐spot monitoring of cocaine in oral fluids and urine continues to be an important toxicological issue. In terms of drug testing, a number of devices have been introduced into the market in recent decades, notably for workplace inspection or roadside testing. However, these systems do not always fulfill the requirements in terms of reliability, especially when low cut‐off levels are required. With respect to surface water, the presence of anthropogenic small organic molecules such as prescription and over‐the‐counter pharmaceuticals as well as illicit drugs like cannabinoids, heroin, or cocaine, has become a challenge for scientists to develop new analytical tools for screening and on‐site analysis because many of them serve as markers for anthropogenic input and consumer behavior. Here, a modular approach for the detection of cocaine is presented, integrating an electrochemical enzyme‐linked immunosorbent assay (ELISA) performed on antibody‐grafted magnetic beads in a hybrid microfluidic sensor utilizing flexible tubing, static chip and screen‐printed electrode (SPE) elements for incubation, recognition, and cyclic voltammetry measurements. A linear response of the sensor vs. the logarithm of cocaine concentration was obtained with a limit of detection of 0.15 ng/L. Within an overall assay time of 25 minutes, concentrations down to 1 ng/L could be reliably determined in water, oral fluids, and urine, the system possessing a dynamic working range up to 1 mg/L. KW - ELISA KW - Kokain KW - Lab-on-chip KW - Speichel KW - Urin KW - Drogenanalytik KW - Schnelltest KW - Biosensor PY - 2018 DO - https://doi.org/10.1002/dta.2515 SN - 1942-7611 VL - 11 IS - 3 SP - 492 EP - 500 PB - Wiley-VCH CY - Hoboken, New Jersey, USA AN - OPUS4-46888 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf J. T1 - Evaluating the Normalization Potential of Anthropogenic Markers in Wastewater: Monitoring Influents of German Treatment Plants by ELISA N2 - Wastewater-based epidemiology (WBE) has emerged as a vital tool for pandemic preparedness, offering early warning capabilities and supporting public health interventions. In Germany, combined sewer systems are prevalent, leading to fluctuations in wastewater volume and com-position due to rainwater inflow, especially through street drains. This variability complicates the quantitative measurement of pathogens and pollutants in wastewater. While human excretion provides constant inputs, these parameters are often non-specific, lost, or degraded during transport. Pharmaceuticals—such as carbamazepine, diclofenac, and clarithromycin—as well as commonly consumed substances like caffeine, exhibit sufficiently high concentrations and good chemical stability in wastewater and are not subject to seasonal fluctuations. Antibody-based methods, particularly Enzyme-Linked Immunosorbent Assays (ELISA), offer a cost-effective alternative to complex chromatographic techniques for monitoring anthropogenic markers. They demonstrate superior normalization quality compared to the frequently used quantitative PCR-based marker Pepper mild mottle virus (PMMoV). T2 - 6th International Conference on Risk Assessment of Pharmaceuticals in the Environment - ICRAPHE CY - Aveiro, Portugal DA - 20.10.2025 KW - Carbamazepin KW - Koffein KW - Spurenstoffe KW - Anthropogener Marker Immunoassay PY - 2025 AN - OPUS4-64432 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Murine hybridoma cells can be specifically labeled and sorted by Flow Cytometry (FACS) in order to select clones for mab production T2 - Proteomics Forum CY - Berlin, Germany DA - 2011-04-03 PY - 2011 AN - OPUS4-24950 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -