Towards Detection of Total Antioxidant Concentrations of Glutathione, Cysteine, Homocysteine and Ascorbic Acid Using a Nanocarbon Paste Electrode

Abstract

The electrocatalytic reaction between catechol and the antioxidants, glutathione, cysteine, homocysteine and ascorbic acid is studied at a nanocarbon paste electrode and used to measure the total antioxidant concentration in aqueous solution. Two different approaches are described: one in which catechol is dissolved in solution and the second in which catechol is dissolved into the nanocarbon paste electrode. Similar limits of detection of 2.0μM and 1.9μM and sensitivities of 8.8×10-3μA/μM and 0.11μM-1 are reported, respectively at nanocarbon and nanocarbon-catechol paste electrodes. Three different commercial multivitamin drug samples were analysed and the results were in a good agreement with those from independent analysis. © 2014 The Authors