Building an aptamer/graphene oxide FRET biosensor for one-step detection of bisphenol A

Bisphenol A (BPA) is an important industrial chemical for polycarbonate (PC) and epoxy resins in paper and plastic industries. In our work, a kind of new method for detection of BPA was designed based on graphene oxide and anti-BPA aptamer. The graphene oxide can specifically adsorb and quench the fluorescence of fluorescently modified ssDNA probes. Meanwhile, the BPA can combine with anti-BPA optamer and switch its configuration to prevent the aptamer from adsorbing on the surface of graphene oxide (GO). Under different concentrations of BPA, based on the target-induced conformational change of anti-BPA aptamer and the interactions between the fluorescently modified anti-BPA aptamer (FAM-ssDNA) and GO, the experimental results show that the intensity of the fluorescence signal was changed. A low limit of detection of 0.05 ng/mL was obtained in the range 0.1-10 ng/mL. In addition, the specificity was outstanding among analogues of BPA. The recovery rate in actual water samples spiked with BPA can be 96.0% to 104.5%. The developed method was successfully used to determine BPA in actual water samples.