Electrochemical Determination of Carbendazim in Food Samples Using an Electrochemically Reduced Nitrogen-Doped Graphene Oxide-Modified Glassy Carbon Electrode

Nitrogen-doped graphene oxide (NGO) was synthesized via pyrolysis of graphene oxide and urea and was characterized by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). An electrochemically reduced nitrogen-doped graphene oxide-modified glassy carbon electrode (ERNGO/GCE) was developed for the determination of carbendazim (CBZ) in food samples. The surface morphology of the modified electrode was characterized by scanning electron microscopy (SEM). Cyclic voltammetry and electrochemical impedance spectroscopy were employed to demonstrate the large electrode surface and fast electron transfer of the ERNGO/GCE. Electrochemical behaviors of CBZ at different electrodes were studied by voltammetry. Experimental results showed that the ERNGO/GCE achieved better performance for the electrochemical oxidation of CBZ than either the bare glassy carbon electrode (GCE) or the nitrogen-doped graphene oxide-modified GCE (NGO/GCE). Under optimized conditions, the ERNGO/GCE exhibited a wide linearity of 5.0~850 μg/L with a detection limit of 1.0 μg/L (signal-to-noise ratio = 3). Application of our proposed method in food products was shown to be practical and reliable.