Modified multiwalled carbon nanotubes paste electrode as a sensor for the electrocatalytic determination of N-acetylcysteine in the presence of high concentrations of folic acid

Abstract

A new vinylferrocene modified-multiwalled carbon nanotubes paste electrode was prepared and used for the determination of N-acetylcysteine (N-AC) and folic acid (FA). Using the modified electrode, a highly selective square wave voltammetric method for the simultaneous determination of N-AC and FA was developed. The peak currents of N-AC and FA increased linearly with their concentration in the ranges of 0.1–662 and 10.0–900 μmol L⁻¹, respectively, with corresponding detection limits of 0.09 and 7.0 μmol L⁻¹. The RSD% for 0.7 μmol L⁻¹N-AC was 1.5%, whereas for 15.0 μmol L⁻¹ FA, it was 1.9%. Well separated oxidation peaks of N-AC and FA were obtained at pH 7.0 with this modified electrode. The modified electrode was successfully applied for the simultaneous determination of N-AC plus FA in real samples.