A Graphene-Based Electrochemical Sensor for Sensitive Detection of Vanillin

A simple and rapid electrochemical method was developed for the determination of trace-level vanillin, based on the excellent properties of graphene. The graphene film-coated glassy carbon electrode (GCE) was constructed and the electrochemical behavior of vanillin at the electrode was investigated in detail. The results indicated that graphene modified GCE exhibited efficiently electrocatalytic oxidation for vanillin with relatively high sensitivity and stability. The electrocatalytic behavior was further exploited as a sensitive detection scheme for the analyte determinations by differential pulse voltammetry (DPV). Under the optimized conditions, the oxidation peak current was proportional to vanillin concentration in the range of 6.0×10−7 to 4.8×10−5 mol L−1 with the correlation coefficient of 0.9996 and the detection limit of 5.6×10−8 mol L−1 (S/N = 3). The proposed method was successfully applied to biscuits samples with satisfactory results. The recovery of the method was in the range of 97.9-103.5%.