Abstract: The fluorescence response signals of supramolecular inclusion complexes of AFG1 with β-cyclodextrin or its derivatives were studied. The fluorescence response signal of AFG1-HE-β-CD reaction system was significantly enhanced compared with AFG1, which reached maximum level after 3 min reation in 2% methanol solution HE-β-CD at the HE-β-CD cocnentration of 0.05 mol/L. According to the Benesi-Hidebrand equation, an inclusion complex was formed from AFG1 and HE-β-CD at a ratio of 1:1. UV spectroscopic, infrared spectroscopic and thermodynamic analyses and KI quenching experiments showed that AFG1 entered the cavity of HE-β-CD so that its fluorescence intensity was protected. An excellent linear relationship with fluorescence intensity was observed in the AFG1 concentration of 2－40 μg/kg (r = 0.9998). The detection limit was 0.079 μg/L. Therefore, the application of HE-β-CD can permit the accurate and precise analysis of AFG1 in peanut samples.

Key words: β-cyclodextrin, aflatoxin G1, fluorescence enhancement, supramolecular inclusion