Voltammetric determination of L-dopa using a carbon nanotubes-Nafion modified glassy carbon electrode

A method for determination of L-dopa by the adsorption stripping voltammetry (ASV) using a multiwalled carbon nanotubes (MWNTs)-Nafion modified glassy carbon electrode (GMGCE) was proposed. This chemically modified electrode (CME) shows a better stability. A sensitive oxidation peak was observed and the anodic peak potential is ca. 0.374V ( vs. SCE). The influences of various experimental parameters on the current peak were completely studied. Under the optimized condition, the method has been applied to the determination of L-dopa in samples. There is a good linear relationship between the peak current (i(p)) and L-dopa concentration in the range of 3.5 x 10(-7) similar to 1.5 x 10(-5) mol/L, with the limit of detection 5.0 x 10(-8) mol/L.