Voltammetric Determination of UricAcid on Poly(- Aminobenzene Sulfonic Acid)-Modified Glassy Carbon Electrode

Abstract

A stable modified glassy carbon electrode based on poly (p-aminobenzene sulfonic acid) (p-ABSA) film was prepared by electrochemical polymerization technique in phosphate buffer solution (PBS) (pH 7.0) and its electrochemical behavior were studied by cyclic voltammetry (CV). The polymer film-modified electrode has been used for investigation of the dermination of uric acid (UA). The peak potential values for the oxidation processes of 5x10-5 M UA on a bare glassy carbon electrode and the p-ABSA modified glassy carbon electrode surfaces has been obtained at about 509 mV and 309 mV by differential pulse voltammetry (DPV) technique, respectively. The modified glassy carbon electrode had an excellent response and specificity for the electrocatalytic oxidation of UA in PBS (pH 7.0). A linear calibration curve for DPV analysis was constructed in the uric acid concentration range 1x10-5- 1x10-4 M. Limit of detection (LOD) and limit of quantification (LOQ) at p-ABSA modified electrode were obtained as 1.125x10-6 M and 3.750x10-6 M, respectively. This electrode was used for UA determinations in human urine samples satisfactorily.