The Application of Alumina for Electroanalytical Determination of Gallic Acid

A novel and simple electrochemical sensor for the determination of gallic acid is presented. The alumina sample was characterized by X-ray diffraction, FTIR, and particle size distribution analysis. The carbon paste electrode was modified with alumina and used as a sensor. The performances of the sensor were assessed by cyclic voltammetry and square-wave voltammetry techniques. The oxidation of gallic acid on alumina-modified carbon paste electrode was an irreversible diffusion-controlled process. The linear relationship of peak current and concentration was obtained for the concentration range of 1.4 to 115 µM with the limit of detection of 0.8 µM. The sensor’s ability to test gallic aid in real systems was successfully tested in wine samples.