Development of a rapid magnetic bead-based immunoassay for sensitive detection of zearalenone.

Here we demonstrate a novel magnetic bead-based enzyme-linked immunosorbent assay (MB-ELISA) for zearalenone (ZEN) detection. Firstly, an anti-ZEN monoclonal antibody (mAb) was prepared by hybridoma technique, and immobilized on carboxyl modified MBs to obtain mAb-MBs. In addition, the biotinylated ZEN-BSA was labelled by streptavidin-HRP for use as competitor. Based on the mAb-MBs and streptavidin-HRP labelled ZEN-BSA, a MB-ELISA which contains only one 20 min antigen-antibody reaction step and takes no more than 45 min for dozens of samples analysis was developed. The half maximal inhibitory concentration (IC50) and limit of detection (LOD) of the MB-ELISA are 1.78 ng/mL and 0.13 ng/mL, respectively. And the MB-ELISA working range for corn samples analysis is from 5.0 μg/kg to 255.2 μg/kg. The recoveries for ZEN spiked corn samples ranged from 82.3 to 110.5% with coefficient of variation (CV) under 8.9%. For natural corn samples analysis, the results of MB-ELISA showed good agreement with the results of conventional direct competitive ELISA (R2 = 0.9742).