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 mu M with the limit of detection of 0.8 mu M. The sensor's ability to test gallic aid in real systems was successfully tested in wine samples.