TY - GEN A1 - Schneider, Rudolf T1 - Fluorescence polarization immunoassays - Comparison of platforms N2 - Immunoassays are in the majority of formats heterogeneous assays with one of the commodities – antibody or antigen – immobilized on a solid substrate or sometimes to nanoparticles or beads. All these formats require a washing step in order to separate bound from non-bound species before generating the measurement signal. Measuring fluorescence polarization is a method to distinguish between a fluorescent macromolecule and a low-molecular weight fluorophore. After irradiation of the sample with polarized light, a macromolecule like e.g. an antibody, will emit still highly polarized light (high polarization, resp. small difference in degree of polarization to the background). In a fluorescence polarization immunoassay, the fluorescence of an analyte surrogate (a fluorescence “tracer”) is followed. Depolarization is high and so the measured polarization is low. When antibody is added, the tracer is bound, depolarization decreases and the in polarization is high. Increasing amounts of analyte more and more impede the tracer being bound by the tracer and thus the decreases, the typical sigmoidal relationship is obtained (Fig. 1). We dispose of 5 polarization platforms reading in plate mode, strip mode and cuvette mode. One is able to register polarization changes with time and so allows for kinetic measurements another one is hand-held. We have been comparing FPIA formats before [1-4] and now a comprehensive view on sensitivities, the importance of fast vs. slow binding kinetics as well as the choice of format can be presented. T2 - BioSensor 2017 - 1st European and 10th German BioSensor Symposium CY - Potsdam, Germany DA - 20.03.2017 KW - FPIA KW - Immunoassay KW - Fluoreszenz PY - 2017 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/43523 AN - OPUS4-43523 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany