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 U6 - 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 -