Development of a class-specific immunoassay for the type I pyrethroid insecticides Original Research Article

A general enzyme-linked immunosorbent assay was developed for the type I pyrethroid insecticides, such as permethrin, phenothrin, resmethrin and bioresmethrin. Polyclonal antibodies were generated by immunizing with a permethrin derivative, 2,2-dimethyl-3-(5′-carboxy-pent-1′-en-yl)cyclopropanecarboxylic acid-(3-phenoxybenzyl)ester conjugated with thyroglobulin, bovine serum albumin or ovalbumin. Antisera were screened against eight different coating antigens. The antibody–antigen combination with the lowest background, and highest sensitivity for permethrin was further optimized and tested for solvent and detergent tolerance. The I50’s of the optimized immunoassay were 30 μg/l for permethrin and 20 μg/l for phenothrin, respectively. No cross-reactivities were measured to the type II pyrethroids, such as esfenvalerate, cyfluthrin, cypermethrin, deltamethrin, fenvalerate and fluvalinate. This assay can be used in monitoring studies to distinguish between types I and II pyrethroids.