Sensitive determination of kojic acid in foodstuffs using PVP (polyvinylpyrrolidone) modified acetylene black paste electrode

The voltammetric behaviors of kojic acid (KA) were investigated at polyvinylpyrrolidone (cross-linked) modified acetylene black paste electrode (denoted as PVP/ABPE) in 0.1 mol/L, pH 5.0 HAc-NaAc buffer. A well-defined and sensitive oxidation peak appears at 0.84 V. Compared with an unmodified acetylene black paste electrode (ABPE), the PVP/ABPE remarkably enhances the oxidation peak current of kojic acid, indicative of good potential in sensitive determination of kojic acid. After optimization of experimental conditions, a fast and sensitive electrochemical method was developed for the determination of kojic acid. This method exhibits good linearity over the range from 1.0 x 10(-6) mol/L to 1.0 x 10(-4) mol/L, and the detection limit is as low as 5.0 x 10(-7) mol/L. In order to validate the feasibility of this proposed method, it was used for quantitative analysis of kojic acid in some food samples and the results were satisfying. (c) 2006 Elsevier Ltd. All rights reserved.