Graphitic Carbon Nitride as a New Sensitive Material for Electrochemical Determination of Trace Amounts of Tartrazine in Food Samples

In this work, g-C3N4 was successfully fabricated by direct pyrolysis of the melamine, and then without any modification, was used to prepare g-C3N4/graphite pencil electrode. The maximum current at this working electrode was depended significantly by the pH value; thus, the g-C3N4/tartrazine interaction is pH-dependent and the best pH was obtained in an acidic medium at pH 2.1. Cyclic voltammetry and differential pulse voltammetry were used to investigate the electrochemical behavior of tartrazine. Differential pulse voltammetry under the optimized experimental conditions showed that the electrochemical current of the sensor was linear to the concentration of tartrazine in dynamic range of 1.0 x 10(-7) to 1.0 x 10(-5) mol L-1. The detection limit of tartrazine was found to be 0.21 mu mol L-1. In addition, this method is simple, environmental friendly, and economical for rapid and precision determination of trace amounts of tartrazine in real samples. This electrode has a good stability and repeatability.