Development of an immunochromatographic strip test for the rapid detection of zearalenone in corn.

A rapid immunochromatographic test strip has been developed for the detection of zearalenone (ZEN) residues in corn. For this purpose, a specific anti-ZEN monoclonal antibody (mAb), 4A3-F9, was obtained and identified. ZEN coupled to bovine serum albumin (BSA) via 1,4-butanediol diglycidyl ether was prepared as immunogen. The mAb showed low cross-reactivity with five ZEN analogues. Using an antibody preparation with a titer of ≥1:5.12 × 10(5), the cross-reactivity (CR) of the anti-ZEN monoclonal antibody with four of the analogues was <4%, except for zearalanone, which was 53.121%. The recovery rates of ZEN in spiked corn samples were in the range of 91.30-97.07% with coefficients of variation <5.32%. An immunochromatographic strip was developed using the specific anti-ZEN monoclonal antibody and applied to the screening of corn samples for ZEN residues. The test could be accomplished within 5-10 min. The sensitivity of the test strip in corn sample extract was confirmed to be 20 μg/kg by unaided visual assessment, and the IC50 was calculated as 3.4 ng/mL using a test strip reader. The test strip, analyzed by unaided visual assessment and strip reader, showed very good agreement with competitive indirect ELISA and high-performance liquid chromatography (HPLC) analysis for naturally contaminated corn samples.