TY - JOUR A1 - Ecke, Alexander A1 - Westphalen, Tanja A1 - Hornung, J. A1 - Voetz, M. A1 - Schneider, Rudolf T1 - A rapid magnetic bead-based immunoassay for sensitive determination of diclofenac N2 - Increasing contamination of environmental waters with pharmaceuticals represents an emerging threat for the drinking water quality and safety. In this regard, fast and reliable analytical methods are required to allow quick countermeasures in case of contamination. Here, we report the development of a magnetic bead-based immunoassay (MBBA) for the fast and cost-effective determination of the analgesic diclofenac (DCF) in water samples, based on diclofenac-coupled magnetic beads and a robust monoclonal anti-DCF antibody. A novel synthetic strategy for preparation of the beads resulted in an assay that enabled for the determination of diclofenac with a significantly lower limit of detection (400 ng/L) than the respective enzyme-linked immunosorbent assay (ELISA). With shorter incubation times and only one manual washing step required, the assay demands for remarkably shorter time to result (< 45 min) and less equipment than ELISA. Evaluation of assay precision and accuracy with a series of spiked water samples yielded results with low to moderate intra- and inter-assay variations and in good agreement with LC–MS/MS reference analysis. The assay principle can be transferred to other, e.g., microfluidic, formats, as well as applied to other analytes and may replace ELISA as the standard immunochemical method. KW - Immunoassay KW - Magnetic beads KW - Diclofenac KW - Water analysis KW - LC-MS/MS PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542346 DO - https://doi.org/10.1007/s00216-021-03778-7 SN - 1618-2650 VL - 414 SP - 1563 EP - 1573 PB - Springer CY - Heidelberg AN - OPUS4-54234 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Devi, Sarita A1 - Riedel, Soraya A1 - Döring, Sarah A1 - Hiller, Lukas A1 - Kaliyaraj Selva Kumar, Archana A1 - Flemig, Sabine A1 - Singh, Chandan A1 - Konthur, Zoltán A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf T1 - Antibodies Functionalized Magnetic Fe-Metal-Organic Framework Based Biosensor for Electrochemical Detection of Tetanus Neurotoxin N2 - This work presents a metal-organic framework (MOF)-integrated microfluidic flow-cell (MFC) based immunodetection of the tetanus toxoid (TT) using electrochemical technique for the first time. The magnetic property of Fe-MOF helped to hold them on the working electrode at detection zone of MFC surpassing the requirement of additional conjugation chemistry, whereas the conductive property was utilized to observe the change in signal efficiency in the presence of TT. The one-pot hydrothermal synthesis of a magnetic and conductive iron-based MOF (Fe-MOF) was performed using the Fe3 +/Fe2+ precursors as 1.2/1 mmol and dual ligands, i.e., tetrahydroxy-1,4-benzoquinone and 2-aminobenzene-1,4-dicarboxylic acid. The Fe-MOF was conjugated with L-phenylalanine (Fe-MOF/Phe) to increase its electric conductivity owing to the enhanced electron flow rate. The human monoclonal antibody SA13 against TT (anti-TT mAb) was conjugated on the Fe-MOF/Phe surface with the help of ethylenediamine (Fe-MOF/Phe/EDA/anti-TT mAb). The binding affinity of Fe-MOF/Phe/EDA/anti-TT mAb for the TT antigen was evaluated using cyclic voltammetry technique. The limit of detection of the Fe-MOF/Phe/EDA/anti-TT mAb-based biosensor for TT was 9.4 ng/ml in spiked buffer. This study shows the applicability of these Fe-MOFs in the detection of various other microbial toxins or other biomolecules. KW - Antikörper KW - Elektrochemischer Immunoassay KW - Molecular Organic Framework (MOF) KW - Microfluidics KW - Rekombinant PY - 2025 DO - https://doi.org/10.1016/j.snb.2025.137381 SN - 0925-4005 VL - 431 SP - 1 EP - 12 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-62673 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, Rudolf T1 - Antikörperbasierte vor-Ort-Analytik für das Monitoring der Eliminierung von Spurenstoffen in Kläranlagen N2 - Die Überwachung der Eliminierung von Spurenstoffen in Kläranlagen, wie sie die Neufassung der Kommunalabwasserrichtlinie vorschreibt, ruft einen Bedarf an vor-Ort-Analytik in den Kläranlagen hervor. Immunanalytische Methoden können vor Ort, z.B. in Form von Schnelltests, durchgeführt werden, ideal aber wären kontinuierlich arbeitende (Immuno-Bio)Sensoren. Antikörperbasierte Verfahren weisen als Flaschenhals immanent die Einschränkung auf, dass pro Analyt ein Antikörper zum Einsatz kommen muss und dass daher nur eine kleinere Anzahl von Substanzen analysiert werden kann. Die Indikatorenliste der Abwasserrichtlinie liefert hier einen Anhaltspunkt. Der Artikel weist schon bisher existierende Schnell- und Hochdurchsatzverfahren aus, ebenso wie Forschungsansätze für eine Sensorik, die online einsetzbar wäre und gibt einen Überblick über Defizite und Entwicklungen. KW - Antikörper KW - Immunoassay KW - Schnelltests KW - Biosensor PY - 2025 SN - 1618-3258 VL - 31 IS - 1 SP - 12 EP - 14 AN - OPUS4-63510 LA - deu 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 - Riedel, Soraya A1 - Hülagü, Deniz A1 - Bennet, Francesca A1 - Carl, Peter A1 - Flemig, Sabine A1 - Schmid, Thomas A1 - Schenk, J. A. A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf T1 - Electrochemical Immunomagnetic Ochratoxin A Sensing: Steps Forward in the Application of 3,3’,5,5’- Tetramethylbenzidine in Amperometric Assays N2 - Electrochemical methods offer great promise in meeting the demand for user-friendly on-site devices for Monitoring important parameters. The food industry often runs own lab procedures, for example, for mycotoxin analysis, but it is a major goal to simplify analysis, linking analytical methods with smart technologies. Enzyme-linked immunosorbent assays, with photometric detection of 3,3’,5,5’-tetramethylbenzidine (TMB),form a good basis for sensitive detection. To provide a straightforward approach for the miniaturization of the detectionstep, we have studied the pitfalls of the electrochemical TMB detection. By cyclic voltammetry it was found that the TMB electrochemistry is strongly dependent on the pH and the electrode material. A stable electrode response to TMB could be achieved at pH 1 on gold electrodes. We created a smartphonebased, electrochemical, immunomagnetic assay for the detection of ochratoxin A in real samples, providing a solid basis forsensing of further analytes. KW - Ochratoxin A KW - Amperometry KW - Cyclic voltammetry KW - Electrochemistry KW - Immunoassay PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530421 DO - https://doi.org/10.1002/celc.202100446 N1 - Geburtsname von Riedel, Soraya: Höfs, S. - Birth name of Riedel, Soraya: Höfs, S. VL - 8 IS - 13 SP - 2597 EP - 2606 AN - OPUS4-53042 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Riedel, Soraya A1 - Jaut, Valerie A1 - Schneider, Rudolf T1 - Ergometrine sensing in rye flour by a magnetic bead-based immunoassay followed by flow injection analysis with amperometric detection N2 - A certain group of mycotoxins, the ergot alkaloids, has caused countless deaths throughout human history. They are found in rye and other cereals and ingesting contaminated foods can cause serious health problems. To identify contaminated food exceeding the legal limits for ergot alkaloids, a portable and cost-effective test system is of great interest to the food industry. Rapid analysis can be achieved by screening for a marker compound, for which we chose ergometrine. We developed a magnetic bead-based immunoassay for ergometrine with amperometric detection in a flow injection system using a handheld potentiostat and a smartphone. With this assay a limit of detection of 3 nM (1 μg/L) was achieved. In spiked rye flour, ergometrine levels from 25 to 250 μg/kg could be quantified. All results could be verified by optical detection. The developed assay offers great promise to meet the demand for on-site ergometrine detection in the food industry. KW - Ergot alkaloids KW - Amperometry KW - Magnetic beads KW - Immunoassay KW - Food analysis KW - Fow injection analysis KW - Mycotoxins PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565906 DO - https://doi.org/10.1016/j.talanta.2022.124172 SN - 0039-9140 N1 - Geburtsname von Riedel, Soraya: Höfs, S. - Birth name of Riedel, Soraya: Höfs, S. VL - 254 IS - 124172 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-56590 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ecke, Alexander A1 - Westphalen, Tanja A1 - Retzmann, Anika A1 - Schneider, Rudolf T1 - Factors affecting the hydrolysis of the antibiotic amoxicillin in the aquatic environment N2 - The environmental fate of the frequently used broad-spectrum β-lactam antibiotic amoxicillin (AMX) is of high concern regarding the potential evolution of antimicrobial resistance (AMR). Moreover, it is known that AMX is prone to hydrolysis, yielding a variety of hydrolysis products (HPs) with yet unknown effects. Studies to identify those HPs and investigate their formation mechanisms have been reported but a long-term study on their stability in real water samples was missing. In this regard, we investigated the hydrolysis of AMX at two concentration levels in four distinct water types under three different storage conditions over two months. Concentrations of AMX and four relevant HPs were monitored by an LC-MS/MS method revealing pronounced differences in the hydrolysis rate of AMX in tap water and mineral water on the one hand (fast) and surface water on the other(slow). In this context, the occurrence, relative intensities, and stability of certain HPs are more dependent on the water type than on the storage condition. As clarified by ICP-MS, the main difference between the water types was the content of the metals copper and zinc which are supposed to catalyze AMX hydrolysis demonstrating an effective method to degrade AMX at ambient conditions. KW - β-lactam KW - Stability KW - Degradation KW - Hydrolysis products KW - LC-MS/MS KW - ICP-MS PY - 2023 DO - https://doi.org/10.1016/j.chemosphere.2022.136921 SN - 0045-6535 VL - 311 SP - 136921 PB - Elsevier Ltd. AN - OPUS4-56124 LA - eng 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 T1 - How can antibodies help us in the risk assessment of pharmaceuticals in the environment? N2 - The widespread use of pharmaceuticals has led to their persistent presence in various environmental compartments, raising concerns about ecological and human health risks since they pose a significant threat to non-target organisms and human health, necessitating robust methods for environmental risk assessment.   Traditional analytical methods, such as liquid chromatography-mass spectrometry (LC-MS), offer high sensitivity and specificity but are often resource-intensive, require complex sample preparation, limiting their applicability for large-scale or real-time monitoring. In this context, antibody-based analytical techniques present a promising complementary approach for the detection and quantification of pharmaceutical residues in environmental matrices.   Antibodies, due to their high specificity and affinity, enable the development of immunoassays such as ELISA, lateral flow assays, fluorescence-based formats, and electrochemical sensors that are rapid, cost-effective, and adaptable to field conditions. These methods can be tailored to target a wide range of pharmaceutical compounds, including antibiotics and endocrine disruptors. Moreover, antibody-based assays facilitate high-throughput screening and can be integrated into portable platforms for on-site analysis, thereby enhancing temporal and spatial resolution in environmental monitoring.   This presentation explores the potential of antibodies in environmental risk assessment, focusing on their application in detecting trace levels of pharmaceuticals in water, soil, and biota. They are presented as a complementary and powerful tool for rapid, cost-effective screening in the lab and that also can be deployed for on-site analysis in the field.   The talk also discusses recent advances in antibody engineering, multiplexing capabilities [1], and the integration of immunoassays with sensor technologies [2].   Case studies illustrate how immunoanalytical data can help in finding potential contamination hotspots [3], hazard identification, pollution source tracking, and the generation of crucial data for predictive models on environmental fate and effects. Antibody-based methods can also help in early warning systems and the evaluation of mitigation strategies, contributing to a more comprehensive and proactive risk assessment framework, eventually to regulatory decision-making, ultimately aiding in the protection of ecosystems and public health. T2 - ICRAPHE - 6th International Conference on Risk Assessment of Pharmaceuticals in the Environment CY - Aveiro, Portugal DA - 20.10.2025 KW - Antibodies KW - Immunoassay KW - Microfluidics KW - Electrochemical detection KW - Biosensor PY - 2025 AN - OPUS4-64922 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Rudolf T1 - Immunochemical sensing of key pollution indicators in the water cycle N2 - Organic micropollutants - often termed emerging contaminants - are increasingly detected throughout the water cycle, from drinking water to wastewater. Monitoring their distribution requires trace analytical methods that are fast, cost-effective, matrix-tolerant, and ideally portable. Immunoanalytical techniques, using antibodies, nanobodies, or fragments, offer high selectivity and sensitivity, though typically in single-analyte or oligoplexing formats. To maximize their utility, environmentally relevant indicator compounds should be selected to reflect pollutant input, partial removal during treatment, and persistence in wastewater and surface water. ELISA remains a robust method for high-throughput analysis. We have assays available for the com-pounds carbamazepine, diclofenac, cetirizine, estrone, sulfamethoxazole, caffeine, cocaine, bisphenol A, and isolithocholic acid. Simpler formats like fluorescence polarization immunoassays (FPIA) and lateral flow immunoassays (LFIA)—familiar from COVID-19 rapid tests — enable on-site screening. Multiplexing is feasible with bead-based microarrays and electrochemical sensors on microfluidic platforms, which additionally offer portability and the latter even independence from optical systems. Despite these advances, the development of highly selective, high-affinity binders remains a critical bottleneck. Promising strategies to overcome this include computational hapten design, nanobody engineering, and in silico optimization of binder sequences—enhanced by artificial intelligence for targeted database mining. These approaches, coupled with scalable recombinant expression, are poised to expand the binder repertoire essential for any immunoanalytical platform. This growing repository will be key to advancing immunochemical diagnostics across the water cycle. T2 - 5th International Symposium on Nanobody for Immunological Analysis and Application CY - Guangzhou, China DA - 15.11.2025 KW - Antibodies KW - Immunoassay KW - Microfluidics KW - Biosensor KW - Trace substances KW - Electrochemical detection PY - 2025 AN - OPUS4-64923 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -