Efficient electrocatalytic oxidation and selective determination of isoniazid by Fe(tmphen) 3 2+-exchanged Nafion®-modified electrode

Abstract

Cyclic voltammetry and electrochemical impedance studies of Fe(tmphen) 3 2+ (where tmphen=3,4,7,8-tetramethyl- 1,10-phenanthroline)-immobilized Nafion®-modified glassy carbon electrode (GC/Nf/Fe(tmphen) 3 2+) are carried out in 0.1 M Na 2SO 4 solution. Nafion-Fe(tmphen) 3 2+ complex exhibits efficient electrocatalytic oxidation of isoniazid. The linear double reciprocal plot of current and concentration of isoniazid shows a Michaelis-Menten-type catalytic process. The catalytic oxidation currents are proportional to the concentration of isoniazid and show a wide linear calibration range for the quantitative determination of isoniazid. Detection limit and sensitivity are found to be 13 μM and 2.5 μA mM -1, respectively. © Springer-Verlag 2012.