A fluorescence polarization immunoassay method for detection of the bisphenol A residue in environmental water samples based on a monoclonal antibody and 4 '-(aminomethyl)fluorescein

摘要

Based on a sensitive monoclonal antibody against bisphenol A (BPA) and a new tracer named BVA-AMF, a homogeneous fluorescence polarization immunoassay (FPIA) was developed and applied in the determination of bisphenol A in environmental water samples. BVA was selected as the hapten to couple with bovine serum albumin and the conjugate was used as the immunogen for the monoclonal antibody production. Three fluorescein-labeled BVA tracers with different structures (BVA-AMF, BVA-EDF, and BVA-lysFITC) were synthesized. Under the same optimal conditions, BVA-AMF showed the highest sensitivity for FPIA and the detection of BPA exhibited a limit of detection of 5.60 ng mL(-1), an IC50 of 140 ng mL(-1) and a dynamic range of 11.32-904.21 ng mL(-1) approximately. In this assay, the monoclonal antibody against BPA showed high specificity towards BPA with less than 0.15% cross-reactivity against several other similar compounds. Four different kinds of water samples were analyzed, with recoveries being 87.91-114.28%. The detection standard curve of BPA exhibited a good linearity (R-2 = 0.9913, n = 3). Compared with ELISA and HPLC methods, FPIA showed reliability and a high correlation with ELISA of 0.9964 and HPLC of 0.9971. The proposed immunoassay technique is suitable for detection of BPA in authentic environmental water samples.