Biomimetic Enzyme-linked Immunosorbent Assay Using a Hydrophilic Molecularly Imprinted Membrane for Recognition and Fast Determination of Trichlorfon and Acephate Residues in Vegetables

This study describes the development of a new direct competitive enzyme-linked immunosorbent assay method with a hydrophilic imprinted film as biomimetic antibody for determining multi-pesticide residues. The imprinted film, which can selectively recognize trichlorfon and acephate, was synthesized directly on the surface of a 96-well plate using 4-(dimethoxyphosphorothioylamino) butanoic acid as the template molecule. This film exhibited antibody-like recognition ability, fast adsorption-desorption dynamics and good stability. Under optimal conditions, the sensitivity (IC50) of the biomimetic enzyme-linked immunosorbent assay (BELISA) method was 12.0 mg/L for trichlorfon and 30.0 mg/L for acephate. The limit of detection (LOD, IC15) was 8.0 mu g/L for trichlorfon and 12.0 mu g/L for acephate. The developed method was applied to the determination of the trichlorfon and acephate in the spiked asparagus and cucumber samples with recoveries ranging from 72.1 to 92.0 % for trichlorfon and 70.0 to 85.0 % for acephate.