JOURNAL OF ELECTROANALYTICAL CHEMISTRY, cilt.694, ss.94-103, 2013 (SCI-Expanded)
A modified electrode was fabricated by over-oxidation of polymer film after electropolymerization of p-aminophenol on a bare glassy carbon surface. A higher catalytic activity was obtained for electrocatalytic oxidation of ascorbic acid (AA), epinephrine (EN), and uric acid (UA) in pH 7.4 phosphate buffer solution (PBS) at over oxidized poly(p-aminophenol) film modified glassy carbon electrode (Ox-PAP/GCE) due to an enhanced peak current and well-defined peak separations compared with both bare glassy carbon electrode (GCE) and poly(p-aminophenol) film modified GCE (PAP/GCE). The electrode surfaces were characterized by scanning electron microscopy (SEM) and Atomic Force Microscopy (AFM). Individual and simultaneous determination of AA, EN, and UA were carried out by differential pulse voltammetry. The detection limits were individually calculated for ascorbic acid, epinephrine, and uric acid as being 1.0 x 10(-6) M, 6.5 x 10(-9) M, and 1.8 x 10(-7) M, respectively. (c) 2013 Elsevier B.V. All rights reserved.