A facile electrochemiluminescence glucose biosensor based on GOX/Ni(OH)2/Ni foam modified electrode

Selectivity and sensitivity are two important parameters for glucose sensing in clinical and food applications. Glucose oxidase (GOx) which is used for the enzymatic glucose detection, plays a significant role in the selectivity of the biosensor, due to its specific interaction with glucose. The enzymatic glucose biosensors have been developed in three generations during three decades [1-3]. In this study, a new electrochemiluminescence (ECL) glucose biosensor based on immobilization of glucose oxidase into the nickel foam modified electrode was fabricated. Nickel hydroxide was formed on the surface of 3-D Ni foam by a successive scan of cyclic voltammetry in an alkaline solution. The structural characterization of the modified electrode was carried out by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). The electrochemiluminescence method was used for determination of glucose in the aqueous solutions. The fabricated ECL biosensor, GOX/Ni(OH)2/Ni-foam electrode, exhibited excellent electrocatalytic properties toward the detection of glucose in 0.1 M phosphate buffer solution (pH 7.4). The linear range and limit of detection were evaluated to be 2.7×10-9 to 4.5×10-3 M, and 2.0 ×10-9 M (S/N = 3) respectively. The present ECL biosensor exhibited good reproducibility, stability and has been used for determination of glucose concentrations in blood serum samples in the presence of the interference species with the satisfactory results.