Simultaneous Voltammetric Determination of Gallic and Protocatechuic Acids in Mango Juice Using a Reduced Graphene Oxide-Based Electrochemical Sensor

Abstract A simple and sensitive reduced graphene oxide-modified glassy carbon electrode-based electrochemical sensor was used for the concomitant determination of gallic acid (GA) and protocatechuic (PA) acid. The prepared sensor showed a significant enhancement in synergetic electro-catalytic performance towards GA and PA oxidation. A good resolution of the voltammetry peaks was obtained and a method of square wave voltammetry was developed for detection. The modified electrode was characterized by electrochemical techniques. The optimal experimental parameters were considered. GA and PA exhibited a linear increase in the peak currents with their concentrations in the range from 20 to 144 μmol·L？1 for GA and from 20 to 166 μmol·L？1 for PA, with limits of detection (S/N = 3) of 30.8 μmol·L？1 for GA and 10.2 μmol·L？1 for PA. The sensor applicability was simultaneously tested for the analytical determination of GA and PA in mango juice and exhibited a robust functionality. View Full-Tex