Rapid and simple screening analysis for residual imidacloprid in agricultural products with commercially available ELISA

A recently developed monoclonal antibody-based ELISA kit for neonicotinoid insecticide imidacloprid was evaluated for its reproducibility, accuracy, and comparability to results from a conventional high-performance liquid chromatography (HPLC) technique for the determination of residual imidacloprid in agricultural products (cucumber, eggplant, lettuce, and green pepper). A method in which imidacloprid is extracted from each agricultural sample as simple, rapid, and efficient as possible was examined for application to screening field analysis, finally. When each extract was diluted 10-fold and over with water prior to ELISA determination, no significant matrix interference was observed besides spinach. The recovery values from fortified samples and reproducibility were very good (average recovery values greater than or equal to 85.3%; CV values less than or equal to24.0%). The correlation between methods was excellent (r greater than or equal to 0.91). The ELISA kit is a suitable screening method for quantitative and reliable determination of imidacloprid in vegetables even without sample clean-up, which saves time and money and considerably increases sample throughput. (C) 2004 Published by Elsevier B.V.