Poly-dianix blue/multi-walled carbon nanotube modified electrode for detection of levodopa in the presence of high concentrations of ascorbic and uric acids

Abstract

A selective and sensitive electrochemical sensor was studied for determination of levodopa (LD) in the presence of uric acid (UA) and ascorbic acid (AA) using poly-dianix blue and multi-walled carbon nanotubes (PDB/MWCNTs) modified glassy carbon electrode. Cyclic voltammetry, differential pulse voltammetry, and chronoamperometry methods were applied to investigate the electrocatalytic oxidation of LD, UA and AA in aqueous solutions. By DPV technique, LD, UA and AA give oxidation peaks at 0.380, 0.520 and 0.180 V, respectively. Under the optimized experimental conditions LD, UA and AA give a linear response in the range of 0.09-75 μmol L-1, 0.3-110 μmol L-1 and 10-160 μmol L-1, respectively. Accordingly, the obtained detection limits were 0.003, 0.002 and 0.023 μmol L-1. The method provides a simple electrochemical sensor for successful determination of LD in human blood serum samples.