A Sensitive and Specific Monoclonal Antibody Based Enzyme-Linked Immunosorbent Assay for the Rapid Detection of Pretilachlor in Grains and the Environment

Pretilachlor is a chloroacetamide herbicide mainly used for weed and broadleaf weed control in rice, that is widely utilized in China. In order to detect the residue of pretilachlor in the environment and food, a highly sensitive and specific monoclonal antibody (mAb) against pretilachlor was prepared, and the half maximum inhibitory concentration (IC50) of the monoclonal antibody was validated to be 31.47 ± 2.35 μg/L. An indirect competitive ELISA (ic-ELISA) based on the antibody with a linear range of 6.25~100 μg/L was developed. The specificity of the antibody was explained by computer simulations and experimental validation. The mAb exhibited negligible cross-reactivity towards alachlor, acetochlor, propisochlor, butachlor, and metalaxyl, and the limits of detection (LOD) for pretilachlor in lake, rice, and soil samples were 4.83~5.23 μg/L. The recoveries of all samples were 78.3~91.3%. The reliability of the ic-ELISA method for residue detection of pretilachlor in the environment and grains was confirmed using high performance liquid chromatography.