Development, Characterization and Application of a Carbon‐Based Nanomaterial Composite as an Electrochemical Sensor for Monitoring Natural Antioxidant (Gallic Acid) in Beverages

Abstract

Gallic acid (GA) is an important organic acid, found in many natural plants and in food beverages. Here in, we have developed a chemical sensor for the monitoring of GA in wine, green tea and fruit juices. The oxidation of GA was found to be an irreversible process and the corresponding mechanism was proposed. The effect of pH on the oxidation behavior was studied and pH‐6.0 was selected as an optimum pH. Based on the scan rate results a linear relation was observed between the square root of scan rate and peak currents for GA, confirming the oxidation of GA as a diffusion controlled process. The kinetic parameters such as diffusion coefficient, heterogeneous rate constant and charge transfer coefficient values were determined. The limit of detection (LOD) and quantification (LOQ) values were calculated as 4.39 × 10‐7 M and 1.46 × 10‐6 M. The repeatability, reproducibility and stability of the developed sensor were examined and the results confirmed that the developed sensor was in superior in condition. Finally, the practical application of the developed sensor was scrutinized for the quantitative estimation of GA in wine, green tea and fruit juices.

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