Abstract
A new sensitive and selective electrochemical sensor was developed for electrocatalytic determination of glutathione (GSH) in pharmaceutical and biological samples. GSH is a tripeptidethiol present in all eukaryotic and probiotic cells. A voltammetric study of GSH has been carried out at the surface of carbon paste electrode modified with multiwall carbon nanotubes in the presence of rutin as a mediator. The electrochemical oxidation of GSH was investigated by cyclic voltammetry, chronoamperometry and square wave voltammetry (SWV) techniques. Under the optimized conditions, the peak current was linear to GSH concentration over the concentration range of 0.3 to 180μmol L(-1) using SWV. The detection limit was 0.09μmol L(-1). The proposed method was successfully applied to the determination of GSH in the urine, tablet and hemolysed erythrocyte samples.