Amperometric biosensor based on electrochemically reduced graphene oxide/poly( m-dihydroxybenzene) composites for glucose determination

A novel amperometric biosensor was designed via immobilization of glucose oxidase (GOD) into the composite films of electrochemically reduced graphene oxide (RGO) and poly(m-dihydroxybenzene) (PmDB). PmDB was first electrodeposited onto the surface of a glassy carbon electrode by electrochemical polymerization of m-dihydroxybenzene in the presence of graphene oxide (GO). Next, the obtained GO/ PmDB composites were electrochemically reduced to RGO/PmDB at a negative potential. The RGO/ PmDB composites were characterized by scanning electron microscopy (SEM), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The RGO/PmDB composites exhibited high electrocatalytic activity towards the oxidation of hydrogen peroxide (H2O2), and therefore, they were used for sensitive glucose determination by immobilizing GOD within the composite films. The as-prepared glucose biosensor exhibited a linear response ranging from 0.5 to 15 mM, a low detection limit of 0.023 mM (S/N = 3). Also, the RGO-/PmDB-based glucose sensor displayed excellent selectivity as well as good reproducibility and stability.