title: Enzyme-linked immunosorbent assay for the pyrethroid permethrin.
abstract: Permethrin is a predominant pyrethroid widely used in agriculture and public health. A competitive enzyme-linked immunosorbent assay (ELISA) for the detection of permethrin was developed. Two haptens, the trans- and cis-isomers of 3-(4-aminophenoxy)benzyl-3-(2, 2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate, were synthesized and conjugated with thyroglobulin as immunogens. Four antisera were generated and screened against six different coating antigens. The resulting ELISA has an I(50) value of 2.50 microg/L and relatively low cross-reactivities with other major pyrethroids, such as esfenvalerate, cypermethrin, deltamethrin, and cyfluthrin. Methanol was found to be the best solvent for this ELISA, with optimal sensitivity observed at a concentration of 40% (v/v). The assay parameters are unchanged at pH values between 5.0 and 8.0, whereas higher ionic strengths (>0.2 M PBS) strongly suppress the absorbances. River water samples fortified with permethrin were analyzed according to this method and validated by GC-MS. Good recoveries and correlation with spike levels were observed, suggesting this immunoassay is valuable for environmental monitoring and toxicological studies at parts per trillion levels of permethrin.
authors.affiliation: Department of Entomology and Department of Civil and Environmental Engineering, University of California, Davis, California 95616, USA.
authors.forename: G
authors.initials: G
authors.lastname: Shan
authors.forename: W R
authors.initials: WR
authors.lastname: Leeman
authors.forename: D W
authors.initials: DW
authors.lastname: Stoutamire
authors.forename: S J
authors.initials: SJ
authors.lastname: Gee
authors.forename: D P
authors.initials: DP
authors.lastname: Chang
authors.forename: B D
authors.initials: BD
authors.lastname: Hammock
mesh_terms: D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D007306:Insecticides / Q000032:analysis*; D026023:Permethrin; D011722:Pyrethrins / Q000032:analysis*; D015203:Reproducibility of Results
chemical_list: D007306:Insecticides; D011722:Pyrethrins; D026023:Permethrin