The direct competitive ELISA based on monoclonal antibody for detecting okadaic acid in seafood

Okadaic acid (OA), a key diarrheic shellfish poisoning (DSP) toxin will possibly arouses DSP symptoms by consuming the contaminated shellfish. The DSP toxins are stable at high temperatures, and long-term DSP toxicity is carcinogenic. Therefore a fast and reliable analytical method for the detection of OA and analogues in shellfish is worth developing. In this paper, a direct competitive ELISA (dcELISA) for detecting OA in seafood was developed based on monoclonal antibody (McAb). The regression equation of direct competitive ELISA was y=-38.831X+130.25 with a coefficient correlation of R²=0.989 8. The linear range and the limit of detection (LOD) were 1.56-75 ng/mL and 1.09 ng/mL, respectively. The average recovery of OA-spiked sample was 86.05% with the coefficient of variation (CV) of 7.83%. The results indicated that the developed dcELISA is a fast, sensitive and convenient assay and could be used for detecting of OA in seafood.