Analytical Sciences

Abstract − Analytical Sciences, 23(5), 563 (2007).

Self-doped Anthranilic Acid-Pyrrole Copolymer/Gold Electrodes for Selective Preconcentration and Determination of Cu(I) by Differential Pulse Anodic Stripping Voltammetry
Department of Chemistry, Azad University, Yazd Branch, Yazd, Iran
Electropolymerization of anthranilic acid/pyrrole (AA/PY) at solid substrate electrodes (platinum, gold, and glassy carbon) gave stable and water-insoluble films under a wide range of pH. Combining high conductivity of the polypyrrole (PPY) and pH independence of the electrochemical activity of the self-doped carboxylic acid-substituted polyaniline allows us to prepare an improved functionalized PPY-modified electrode to collect and measure Cu(I) species. The differential pulse stripping analysis of the copper ions using a polyanthranilic acid-co-polypyrrole (PAA/PPY)-modified electrode consisted of three steps: accumulation, electrochemical reduction to the elemental copper and stripping step. Factors affecting these steps, including electropolymerization conditions, accumulation and stripping medium, reduction potential, reduction time and accumulation time, were systematically investigated. A detection limit of 5.3 × 10-9 M Cu(I) was achieved for a 7.0 min accumulation. For 12 determinations of Cu(I) at concentrations of 1.0 × 10-8 M, an RSD of 3.5% was obtained. The log Ip was found to vary linearly with log[CuI] in the concentration range from 7.0 × 10-9 to 1.0 × 10-5 M.