▎ 摘　　要

Aflatoxin as the potent carcinogenic mycotoxin had been received great attention for detection in food industry and safety. Due to low quantity of aflatoxin in food samples, there is a need to develop a sensitive method toward its detection. In the present study, an aflatoxin B1 (AFB1) specific aptasensor with internal complementary sequence was developed for detection of AFB1. The FAM-functionalized aptamer was deposited on the surface of graphene oxide decorated with gold nanoparticles (GO/AuNPs) and following formation of heteroduplex stem -loop structure led to fluorescence quenching of FAM-labeled aptamer. After incubation of proposed aptasensor with AFB1, the aptamer-AFB1 complex resulted to denaturation in stem-loop structure of aptamer which caused restoration of single strand aptamer and recovery of fluorescence. The assay showed a convenient detection response in the range of 0.5-20 pg/mL with a very low detection limit (0.1 pg/mL) and it was highly selective for AFB1 over other mycotoxins.