Electrocatalytic synthesis of poly(2,6-diaminopyridine) on reduced graphene oxide and its application in glucose sensing

Reduced graphene oxide (RGO) was prepared via electrochemical reduction of graphene oxide (GO), and it can effectively catalyze the polymerization of 2,6-diaminopyridine. Poly(2,6-diaminopyridine) (PDAP) deposited on RGO (PDAP-RGO) has good electroactivity in a wide pH range until pH 11.0. Due to the electrocatalytic reduction of H2O2 at the PDAP-RGO, a platform for glucose sensing was constructed by immobilizing glucose oxidase (GOD) into the PDAP-RGO. The proposed glucose sensor exhibited a wide linear range from 0.05 to 6.65 mM, a low detection limit of 0.142 mu M, a good reproducibility and stability. The apparent Michaelis-Menten constant of GOD was also calculated based on the relationship between steady-state current and glucose concentration.