Voltammetric determination of ascorbic acid in foodstuffs using modified carbon paste electrodes

Abstract

Application of differential pulse cathodic stripping voltammetry for determination of ascorbic acid in foodstuffs have been investigated using a carbon paste electrode modified by cobalt(II) phthalocyanine, which was found to facilitate its oxidation and to decrease the necessary overvoltage. The method showed a good linearity up to 70 ppm of ascorbic acid with a detection limit of 0.8 ppm. When applied to analyse the real samples (fruit juices), the results agreed well with those obtained by traditional titrimetric determination.