New voltammetric strategy for simultaneous determination of N-acetylcysteine and folic acid using a carbon nanotube modified glassy carbon electrode

A novel 1-benzyl-4-ferrocenyl-1H-[1,2,3]-triazole (BFT)/carbon nanotube modified glassy carbon electrode (BFT-CNT-GCE) was prepared for the simultaneous determination of N-acetylcysteine (NAC) and folic acid (FA). Cyclic voltammetry (CV), chronoamperometry (CHA), and square wave voltammetry (SWV) methods were used to investigate the modified electrode for the electrocatalytic oxidation of NAC and FA in aqueous solutions. The separation of the oxidation peak potentials for NAC-FA was about 280 mV. The calibration curve obtained for NAC was in the range of 0.1-600.0 mu M. The detection limit (S/N = 3) was 62.0 +/- 2.0 nM for NAC. The diffusion coefficient and the catalytic rate constant for the oxidation of NAC at the modified electrode were calculated as (3.5 +/- 0.2) x 10(-5) cm(2) s(-1) and (9.85 +/- 0.4) x 10(-4) M-1 s(-1), respectively. The method was employed for the determination of NAC and FA in some real samples. (c) 2012 Elsevier B.V. All rights reserved.