Biotin-Streptavidin Enzyme-linked Immunosorbent Assay for the Determination of Dibutyl Phthalate in Beverages and Drinking Water Using a Specific Polyclonal Antibody

摘要

A specific polyclonal antibody targeting dibutyl phthalate (DBP) was obtained, and a sensitive indirect competitive biotin-streptavidin enzyme-linked immunosorbent assay (BA-ELISA) was developed for the determination of DBP in beverages and drinking water. Under optimal conditions, good linearity was achieved within a range of 0.02 to 8.97 μg · L−1. The limit of detection (IC10) was 5 ng · L−1, and the median inhibitory concentration (IC50) was 0.36 μg · L−1. The BA-ELISA was highly selective, with lower cross-reactivity values with DBP analogues (lower than 4 %). Finally, the concentrations of DBP in beverages and drinking water by this method ranged from 0.45 to 7.06 μg · L−1. Satisfactory recoveries (89.5 to 109.5 %) and variation coefficient values (6.0 to 8.7 %) were obtained. The consistency between the results obtained from BA-ELISA and gas chromatography-mass spectrometry (GC-MS) was 98.8 %, which further confirmed that this proposed BA-ELISA immunoassay was reliable, rapid, sensitive, and accurate for monitoring DBP in the environmental samples.