Development of an immunochromatographic assay for hexestrol and diethylstilbestrol residues in milk

Abstract

ABSTRACTHexestrol (HES) and Diethylstilbestrol (DES) are synthetic hormones, which have been found abuse use in animal-origin food production. We developed an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and immune-chromatographic strip to detect these compounds based on monoclonal antibody. Under optimized conditions, the half-inhibition concentration (IC50) values of ic-ELISA were 0.15 µgL−1 and 0.23 µgL−1 for HES and DES, respectively. Spiked milk samples were analyzed. The recovery of both synthetic hormones in the milk samples was 60.48–102.19% (HES) and 89.34–100.16% (DES). In immune-chromatographic assay, the visual cutoff values at 0.5 and 1.0 µgL−1 respectively for HES and DES, which allow us to detect milk samples of a concentration low to 10 µgL−1 for HES and 15 µgL−1 for DES.