A graphene oxide modified carbon ceramic electrode for voltammetric determination of gallic acid

In this paper, a new type of carbon ceramic electrode modified with reduced graphene oxide (RGO) was fabricated via sol-gel method. The constructed electrode was used in square wave voltammetric (SWV) determination of gallic acid (GA). The electrochemical properties of the fabricated electrode and voltammetric behavior of gallic acid were investigated by cyclic voltammetry (CV). The SWV investigation of GA was performed in Britton-Robinson buffer at pH2 as a supporting electrolyte. Under the optimized SWV mode parameters, the oxidation peak current (best measured at 0.57 V vs Ag/AgCl) increased linearly in the wide concentration range from 0.51 to 46.40 mu mol L-1. The calculated values of LOD and LOQ were 0.0867 and 0.263 mu mol L-1, respectively. The presented results were obtained without any preconcentration procedure. During the experiment, the effect of common interfering molecules was also investigated. Finally, the usability of the proposed method was verified by the quantitative analysis of GA in red wine, black tea and white tea samples.