Zhang Shengyi

A novel hydrogen peroxide biosensor based on the BPT/AuNPs/graphene/HRP composite

A novel hydrogen peroxide biosensor based on the BPT/AuNPs/graphene/HRP composite was developed. Firstly, graphene was prepared under the protection of polyvinylpyrrolidone (PVP), and then the AuNPs/graphene composite was synthesized via in situ decoration. Using biphenyldimethanethiol (BPT) as a connector, the AuNPs/graphene composite was immobilized on the surface of the Au electrode, and whereafter the horseradish peroxidase (HRP) was decorated on the surface of the composite by adsorption. The morphology and structure of the products were characterized by XRD, SEM, TEM and UV-visible spectroscopy. The electrocatalytic performance of the resulting BPT/AuNPs/grapheme/HRP composite (namely, biosensor) was studied by electrochemical instrument. The results show that the biosensor has high sensitivity and fast response to H2O2. In the solution of pH 7.4 with potential −0.2 V, the linear response of the biosensor to H2O2 ranges from 5.0×10−6 to 2.5×10−3 M with the detection limit of 1.5×10−6 M.