Electrocatalytic oxidation of NADH by poly-toluidine blue multiwall carbon nanotubes modified glassy carbon electrode

Abstract

This study investigates a new approach to the amperometric determination of NADH using a poly-toluidine blue multiwall carbon nanotubes modified glassy carbon electrode (PTB-MWCNTs/GCE). The currents obtained from the amperometric measurements at optimum conditions (phosphate buffer solution (pH 7.0) containing 0.1 M KCl and constant applied potential: +150 mV vs. Ag/AgCl/3.0 M KCl) were linearly correlated with the NADH concentrations. The calibration curve was obtained for NADH concentrations in a range of 0.1- 100×10–6 mol l–1. The precision of the method was investigated by repeated measurements (n = 10) of the 10 μmol NADH and the relative standard deviation (RSD) was found to be 1.5 %. The limit of detection was found to be 0.04×10–6 mol l–1 for amperometric method.