| Abstract
| - Permethrin is the most popular synthetic pyrethroid insecticide in agriculture and public health. Forthe development of the enzyme-linked immunosorbent assay (ELISA) to evaluate human exposureto permethrin, the glycine conjugate (DCCA-glycine) of a major metabolite, cis/trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (DCCA), of permethrin was established asthe target analyte. Four different types of the cis- and trans-isomers of immunizing haptens weresynthesized as follows: N-(cis/trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carbonyl)glycine(hapten 3), N-(cis/trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carbonyl)-4-amino-l-phenylalanine (hapten 5), N-(N-(cis/trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carbonyl)glycine)amino-6-(2,4-dinitrophenyl)aminohexanoic acid (hapten 9), and N-(cis/trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carbonyl)glycine-4-oxobutanoic acid (hapten 24). Sixteen polyclonal antibodiesproduced against each cis- or trans-hapten−thyroglobulin conjugate as immunogens were screenedagainst numerous hapten−bovine serum albumin conjugates as coating antigens. Six ELISAs withboth a heterologous hapten structure and a heterologous hapten configuration (cis/trans or trans/cis)between antibody and coating antigen showed a high sensitivity for the target analyte. The IC50 was1.3, 2.1, and 2.2 μg/L for the trans-target analyte and 0.4, 2.3, and 2.8 μg/L for the cis-target analyte.The immunizing haptens, except for hapten 5, provided the target specific antibodies. Molecularmodeling of the haptens supported the selection of reasonable immunizing haptens that best mimickedthe target analyte. Hapten 5 was suitable as a coating antigen rather than as an immunogen sinceit had a different geometry. Very low cross-reactivities were measured to permethrin, its free metabolite(DCCA), PBA-glycine conjugate, and glycine. The ELISA will be optimized for the detection of totalcis/trans-DCCA-glycine in human urine samples. Keywords: ELISA; permethrin; glycine conjugate; human exposure; hapten
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