Electrochemical sensing based on graphene oxide/Prussian blue hybrid film modified electrode

Abstract

A novel graphene oxide (GO)/Prussian blue (PB) hybrid film was constructed by electropolymerizing Prussian blue onto the GO modified glassy carbon electrode, and its electrochemical behaviors were studied. Raman spectra were used to investigate the successful formation of the GO/PB hybrid film. Electrochemical experiments showed that the graphene oxide greatly enhanced electrochemical reactivity of the PB. Moreover, a much higher Prussian blue (PB) loading (6.388 × 10 −8 mol cm −2) is obtained as compared to the bare glass carbon surface (3.204 × 10 −9 mol cm −2). The GO/PB hybrid film modified electrode was used for the sensitive detection of hydrogen peroxide. The sensor exhibited a wide linearity range from 5.0 × 10 −6 to 1.2 × 10 −3 M with a detection limit of 1.22 × 10 −7 M (S/N = 3), high sensitivity of 408.7 μA mM −1 cm −2 and good reproducibility. Furthermore, with glucose oxidase (GOD) as a model, the GO/PB/GOD/chitosan composite-modified electrode was also constructed. The resulting biosensor exhibited good amperometric response to glucose with linear range from 0.1 to 13.5 mM at 0.1 V, good reproducibility and detection limit of 3.43 × 10 −7 M (S/N = 3). In addition, the biosensor presented high selectivity and long-term stability. Therefore, the PB/GO hybrid films-based modified electrode may hold great promise for electrochemical sensing and biosensing applications.