Enzyme-linked immunoassay for simultaneous detection of methyl parathion and sibutramine in apple cider vinegar

Methyl parathion, a highly toxic, efficient, and persistent organophosphorus pesticide, is widely used in China. Sibutramine, a non-amphetamine central nervous system depressant, helps lose weight by disrupting hormone regulation, stimulating sympathetic nerves, and suppressing appetite. However, some unethical businesses fail to properly handle raw materials in foods like apple cider vinegar, leading to residual methyl parathion in apples or illegal excessive addition of sibutramine. Therefore, it is imperative to develop an immunoassay for the rapid detection of methyl parathion and sibutramine. The corresponding two haptens were prepared and coupled with the carrier proteins according to methyl parathion-sulfur-bovine serum protein (BSA)/chicken ovalbumin (OVA)-sibutramine (20 : 1 : excess, 15 : 1 : excess, 10 : 1 : excess, and 5 : 1 : excess), and sibutramine-BSA/OVA-methyl parathion (20 : 1 : excess, 10 : 1 : excess: 5 : 1 : excess, and 0 : 1 : excess). The result shows that the inhibition rate of the antibody obtained by methyl parathion-BSA/OVA-sibutramine (20 : 1 : excess) was higher than that of sibutramine-BSA/OVA-methyl parathion, which was 67.93%, and the concentration of methyl parathion was 8.65 ng mL