Simultaneous detection of OTA and AFB ₁ in cereals based on bispecific monoclonal antibody using quantum dot nanobead lateral flow immunoassay

Abstract

Simultaneous contamination of ochratoxin A (OTA) and aflatoxin B1 (AFB1) in cereals are an ongoing global concern. For this reason, a sensitive method for the simultaneous detection of OTA and AFB1 in soybean, corn, and rice is required. Herein, we prepared a bispecific monoclonal antibody (BsMAb) that specifically recognized OTA and AFB1, and subsequently developed a quantum dot nanobead (QB) lateral flow immunoassay (QB-LFIA) based on BsMAb. The half-inhibitory concentrations (IC50) for OTA and AFB1 detection were 0.73 and 0.01 µg/kg in soybean, 1.14 and 0.03 µg/kg in corn, and 1.69 and 0.07 µg/kg in rice, respectively. The average recoveries of OTA and AFB1 were 80.20–130.05% with coefficients of variation below 11%. The performance of the proposed method was compared with that of traditional LFIA, and higher sensitivity was observed. The BsMAb-based QB-LFIA was sensitive and specific for the simultaneous detection of OTA and AFB1 in cereals.