In previous studies, polyclonal antibodies against the organophosphorus insecticide fenthion were obtained and an indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed for this pesticide. In this study, using these antibodies and an enzyme tracer, direct competitive ELISAs for fenthion in microtiter plate and dipstick formats were developed. The microtiter plate ELISA showed an IC50 value of 1.2 μg/L with a detection limit of 0.1 μg/L. The antibodies showed negligible cross-reactivity with other organophosphorus pesticides. The use of the dipstick format using Immunodyne as a support membrane allowed the quick visual detection of fenthion in concentrations >10 μg/L. The IC50 value of the dipstick format using reflectance detection was 15 μg/L with a detection limit of 0.5 μg/L. The recoveries of fenthion from spiked vegetable samples using the two formats without any prior enrichment or cleanup steps were 87-116%.
- Enzyme-linked immunosorbent assay
ASJC Scopus subject areas
- Agricultural and Biological Sciences (miscellaneous)
- Food Science
- Chemistry (miscellaneous)