Development of a highly sensitive and specific monoclonal antibody-based immunoassay for detection of okadaic acid in oysters and green mussels

ABSTRACT Okadaic acid (OA), one of marine biotoxins produced by several species of dinoflagellates, can accumulate in marine animals. The consumption of OA-contaminated seafood can cause diarrhoeic shellfish poisoning. Many countries have established regulatory restriction to limit the level of OA in seafood. In the present study, we report a highly sensitive monoclonal antibody (mAb) against OA produced by a new immunogen. Two monoclonal hybridoma cell lines (M8 and M12) that producing mAb with the best sensitivity and specificity were obtained. The obtained mAb-M12 was used to develop an indirect competitive ELISA (icELISA) with 50% inhibition concentrations of 0.15 ng mL−1 and a working range of 0.02–2.74 ng mL−1. The developed icELISA was more sensitive than the previous reports. HPLC-MS confirmed the accuracy and the working range of icELISA, suggesting that the developed icELISA is suitable for the rapid detection of OA in oysters and green mussels.