Rapid detection of adulteration of dehydroepiandrosterone in slimming products by competitive indirect enzyme-linked immunosorbent assay and lateral flow immunochromatography

ABSTRACT In this study, dehydroepiandrosterone (DHEA) hapten and high sensitivity polyclonal antibody against DHEA were prepared, a competitive indirect enzyme-linked immunosorbent assay (ciELISA) and lateral flow immunochromatography (LFA) for the determination of DHEA in slimming products were developed for the first time. The sample pretreatment was very simple and fast, the limit of detection (LOD) of the ciELISA for DHEA in slimming products was 9.6 μg/kg. The average recoveries of slimming tea, slimming tablets and slimming capsules ranged from 93.2% to 99.4%, 86.8% to 100.0%, and 80.5% to 115.4%, respectively, with the coefficient of variations (CVs) between 7.7% and 14.1%, 2.7% and 11.0%, and 2.2% and 8.6%, respectively. The pAb had negligible cross-reactivity to the structural and functional analogs of DHEA. Simultaneously, the LFA showed a cut-off value of 500 μg/kg in slimming products, and the results could be attained within 3 min. A parallel HPLC analysis in 30 commercial slimming products validated a good agreement with the proposed ciELISA and LFA. GRAPHICAL ABSTRAC