Electrochemical behavior and voltammetric determination of 4-aminophenol based on graphene–chitosan composite film modified glassy carbon electrode

The graphene–chitosan composite film modified glassy carbon electrode (GCE) was fabricated and used to determine 4-aminophenol (4-AP). In 0.1   M pH 6.3 phosphate buffer solution , the redox peak currents of 4-AP increased significantly and the peak-to-peak separation decreased greatly at graphene–chitosan composite film modified GCE compared with bare GCE and chitosan modified GCE, indicating that graphene possessed electrocatalytic activity towards 4-AP. The experimental conditions were optimized and the kinetic parameters were investigated. The oxidation mechanism was discussed. Under the optimal experimental conditions, the oxidation peak current was proportional to 4-AP concentration in the range from 0.2 to 550   μM with the correlation coefficient of 0.9930. The detection limit was 0.057   μM (S/N   =   3). Using the proposed method, 4-AP was successfully determined in water samples and paracetamol tablets with standard addition method, suggesting that this method can be applied to determine 4-AP in environments and pharmaceuticals.