Electrochemical Behaviors of Methocarbamol at an Acetylene Black-Ionic Liquid Modified Carbon Paste Electrode and its Electrochemical Determination

Electrochemical behaviors of methocarbamol (MET) at the bare carbon paste electrode (CPE), acetylene black (AB) modified carbon paste electrode (AB/CPE), an ionic liquid 1-Benzyl-3-Methylimidazole hexafluorophosphate ([BnMIM]PF6) modified carbon paste electrode ([BnMIM]PF6/CPE) and AB-[BnMIM]PF6 modified carbon paste electrode (AB-[BnMIM]PF6/CPE) in PBS (pH = 6.8) were investigated by cyclic voltammetry (CV) and square wave voltammetric (SWV). The experimental results showed that MET at the above metioned four electrodes showed an irreversible electrochemical oxidation process, but at the AB-[BnMIM]PF6/CPE, the oxidation peak potential keep almost constant and the oxidation peak current of MET increased greatly. At the same time, the electrochemical kinetic parameters were determined. Under the optimized electrochemical experimental conditions, the oxidation peak currents were proportional to MET concentration range from 4.0 x 10(-6) to 1.0 x 10(-2) mol L-1 with the detection limit (S/N = 3) of 1.5 x 10(-6) mol L-1. The proposed method was successfully applied in the determination of MET content in commercial tablet samples.