Abstract
Fumonisin FB is produced by Fusarium moniliforme Sheld, of which FB(1) is the most common and the most toxic. The establishment of a rapid detection method is an important means to prevent and control FB(1) pollution. A highly sensitive fluorescent sensor based on an aptamer for the rapid detection of fumonisin B(1) (FB(1)) in corn was established. In this study, 5-carboxyfluorescein (FAM) was labeled on the aptamer of FB(1) (F10). F10 was adsorbed on the surface of graphene oxide (GO) by π-π stacking. The FAM fluorescence signal could be quenched by fluorescence resonance energy transfer between fluorescent molecules and graphene oxide (GO). In the presence of FB(1), the binding efficiency of the aptamer to GO was reduced. Therefore, the content of FB(1) in corn samples was determined by fluorescence measurements of mixed FAM-labeled F10, GO and corn samples. This method had a good linear relationship in an FB(1) concentration range of 0-3000 ng/mL. The equation was y = 0.2576x + 10.98, R(2) = 0.9936. The limit of detection was 14.42 ng/mL, and the limit of quantification was 43.70 ng/mL. The recovery of a spiked standard in the corn sample was 89.13-102.08%, and the time of detection was 30 min.