TY - CONF A1 - Ramos, I. I. A1 - Carl, Peter A1 - Schneider, Rudolf A1 - Segundo, M. A. T1 - Automated bead-based immunoassay for the determination of carbamazepine in wastewater N2 - The improvement of immunoanalytical methods for the determination of pharmaceuticals in wastewaters is a crucial yet challenging endeavor. In this work, the development of an automated miniaturized ELISA based on micro-Bead Injection Spectroscopy (μ-BIS) [1] for the determination of carbamazepine, a widely employed anti-epileptic drug and emergent pollutant [2], was pursued. The experimental workflow comprised the offline functionalization of Sepharose beads with specific anti-CBZ antibodies via affinity immobilization using protein G, and 3 online steps inside the microfluidic analyzer lab-on-valve (LOV): I) packing of the bead column into the detection unit; II) sequential percolation of sample and a CBZ competitor- labeled with horseradish peroxidase (tracer) through the bead column; and III) on-column colorimetric detection employing the enzyme substrate 3,3’,5,5’-tetramethylbenzidine. After each analysis, the bead column was discarded, and the flow cell was washed before receiving new beads. The elimination of manual washing steps is a novel feature compared to batch-wise ELISA, making the method less error-prone and therefore more robust. The replacement of the solid support prevents memory effects and cross-contamination between runs. The use of microparticles as solid support for the molecular recognition elements accounts for high area-to-volume ratios, and low molecular diffusion distances. For that reason, time-to-result was reduced from several hours to less than 10 min. The consumption of reagents was also very low. For instance, only ca. 200 μg of solid support and 900 ng of anti-CBZ antibody were required per determination. At last, the versatility of the LOV platform offers the possibility of adapting the assay to other relevant pharmaceuticals and anthropogenic markers in water. Acknowledgements: Inês I. Ramos thanks FCT (Fundação para a Ciência e a Tecnologia) and POPH (Programa Operacional Potencial Humano) for her grant (SFRH/BD/97540/2013). This work received financial support from the European Union (FEDER funds POCI/01/0145/FEDER/007265) and National Funds (FCT/MEC - Ministério da Educação e Ciência) under the Partnership Agreement PT2020 UID/QUI/50006/2013. Financial support from Deutscher Akademischer Austauschdienst and from Fundação das Universidades Portuguesas under the protocol CRUP-DAAD (Ações Integradas Luso-Alemãs nºE-20/16) is also acknowledged. [1] Gutzman, Y.; Carrol, A. D. Analyst 2006, 131, 809. [2] Murray, K. E.; Thomas, S. M.; Bodour, A. A. Environ. Pollut. 2010, 158, 3462. T2 - ANALÍTICA – 2018 CY - Porto, Portugal DA - 26.03.2018 KW - Lab-on-valve KW - Emerging pollutants KW - Immunoassay KW - Automation PY - 2018 AN - OPUS4-44592 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -