title: Development of enzyme-linked immunosorbent assays for the organophosphorus insecticide EPN.
abstract: Competitive enzyme-linked immunosorbent assays (ELISAs) in indirect and direct format were developed for the quantitative detection of the organophosphorus insecticide EPN. Five EPN derivatives (haptens) were synthesized and coupled to carrier proteins to use as an immunogen or as a competitor. Rabbits were immunized with two of the five haptens coupled to KLH for production of polyclonal antibodies, and the sera were screened against one of the haptens coupled to ovalbumin (OVA). Using the serum with the highest specificity and a coating antigen (hapten-OVA conjugate), an indirect (antigen-coated) ELISA was developed, which showed an IC(50) of 5.6 ng/mL with a detection limit of 0.2 ng/mL (20% inhibition). A direct (antibody-coated) ELISA using an enzyme tracer (hapten-enzyme conjugate) was also developed, which showed an IC(50) of 8.4 ng/mL with a detection limit of 0.9 ng/mL (20% inhibition). The antibodies showed negligible cross-reactivity with other organophosphorus pesticides except with the insecticide parathion-ethyl only in the direct ELISA. The recoveries of EPN from spiked samples determined by the indirect ELISAs were between 37 and 164%.
authors.affiliation: Department of Food Science and Nutrition, Kyungpook National University, Daegu 702-701, Korea.
authors.forename: Jee Youn
authors.initials: JY
authors.lastname: Shim
authors.forename: Young Ah
authors.initials: YA
authors.lastname: Kim
authors.forename: Eun Hye
authors.initials: EH
authors.lastname: Lee
authors.forename: Yong Tae
authors.initials: YT
authors.lastname: Lee
authors.forename: Hye-Sung
authors.initials: HS
authors.lastname: Lee
mesh_terms: D000818:Animals; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006241:Haptens / Q000032:analysis / Q000737:chemistry / Q000276:immunology; D007114:Immunization; D007306:Insecticides / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D009943:Organophosphorus Compounds / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D011817:Rabbits
chemical_list: D006241:Haptens; D007306:Insecticides; D009943:Organophosphorus Compounds