Development of polyclonal antibody based enzyme-linked immunosorbent assay for the analysis of the agricultural insecticide imidacloprid: food quality and safety.

In order to develop an indirect competitive enzyme-linked immunosorbent assay (ELISA) for the insecticide imidacloprid, the anti-imidacloprid polyclonal antibody was produced and the affinity of three different coating antigens with the polyclonal antibody was compared. The antigenic determinant in antigen aiming at the polyclonal antibody was raised and analyzed. The standard curve for imidacloprid had been developed. The effects of organic solvents and buffer ionic strength on the ELISA for insecticide were studied and conditions of analysis were also optimized in this research. Experiment result showed that the coating antigen IMMP-OVA ,whose binding ratio was 14:1, had stronger affinity with the anti-imidacloprid polyclonal antibody than IMMB-OVA and IMEB-OVA ; the IC50 value in the standard curve was 995.4 ng.mL-1 and the limit of detection (LOD) was 30 ng.mL-1; the cross reaction ratios with nitenpyram and acetamiprid were 5.73% and 11.31% respectively.