A nanocomposite electrocatalyst for the electro-oxidation of isoproterenol and its application as a sensor

A novel nanocomposite (GCE/AuNP-DAT) was fabricated via the self-assembly of a thiophenol derivative (3,4-dihydroxyphenyl-azo-2-thiophenol, DAT) on a gold nanoparticle (AuNP)-modified glassy carbon electrode (GCE). This novel modified electrode was investigated using cyclic voltammetry, and the electrode was applied for the electrocatalysis of isoproterenol (IP). The electrocatalytic activity of this nanocomposite was studied, and the reaction mechanism and catalytic rate constant were determined for IP. The GCE/AuNP-DAT did not show any electrocatalytic activity for the oxidation of uric acid, and the oxidation signal for IP was therefore not affected by the presence of uric acid at this electrode; any interference from uric acid in the detection of IP was eliminated by the modified electrode. This electrode was applied as a sensor, and differential pulse voltammetry data obtained using this sensor exhibited a linear dynamic range of 1–1500 μmol/L and a detection limit of 0.46 μmol/L for IP.

Graphical AbstractA nanocomposite electrocatalyst was prepared by immobilizing 3,4-dihydroxyphenyl-azo-2-thiophenol (DAT) on a gold nanoparticle-modified glassy carbon electrode (GCE/AuNPs). The electrocatalyst catalyzed the electrochemical oxidation of isoproterenol via a mediating electrocatalysis mechanism.Figure optionsDownload as PowerPoint slide