Development of Electrochemical Method for the Determination of Chlorzoxazone Drug and its Analytical Applications to Pharmaceutical Dosage Form and Human Biological Fluids

The electrochemical behavior of chlorzoxazone drug at glassy carbon electrode has been investigated for the first time using cyclic and square wave voltammetric techniques. The dependence of the current on pH, concentration, and scan rate was investigated to optimize the experimental conditions for determination of chlorzoxazone. The anodic peak was characterized and the process was diffusion-controlled. The number of electrons transferred in the oxidation process was calculated and a plausible oxidation mechanism was proposed. In the range of 8.0 x 10(-7) to 1.0 x 10(-5) M, the current measured by square wave voltammetry presents a good linear property as a function of the concentration of chlorzoxazone with a detection limit of 4.41 x 10(-8) M with good selectivity and sensitivity. The proposed method was successfully applied to chlorzoxazone determination under physiological condition in pharmaceutical samples and for the detection of chlorzoxazone in human biological fluids. This method can be employed in clinical analysis, quality control, and routine determination of drugs in pharmaceutical formulations.