Novel bispecific monoclonal antibody-based dual-analyte immunochromatographic strip for the detection of aflatoxin B1 and ochratoxin A in cereal samples

We have developed a novel bispecific monoclonal antibody (mAb) for the simultaneous detection of aflatoxin B1 (AFB1) and ochratoxin A (OTA). The specific mAb was used to establish a sensitive competitive direct ELISA (cdELISA) and dual-analyte immunochromatographic strip (immunostrip). The cdELISA achieved IC50 values of 0.06 ng/mL for AFB1 and 1.02 ng/mL for OTA, with limits of detection (LOD) of 0.004 ng/mL and 0.24 ng/mL, respectively. The dual-analyte immunostrip exhibited visual detection limits of 0.5 ng/mL for AFB1 and 5 ng/mL for OTA. Recovery rates for spiked cereal samples ranged from 91 % to 110 % for AFB1 and from 99 % to 107 % for OTA. The analysis of 15 cereal samples using the cdELISA detected AFB1 and OTA contamination consistent with HPLC analysis, validating the reliability of both methods. This bispecific mAb offers a rapid and efficient approach for monitoring AFB1 and OTA in food, enhancing food safety efforts.