Electrochemical Behavior of Atorvastatin at Glassy Carbon Electrode and its Direct Determination in Pharmaceutical Preparations by Square Wave and Differential Pulse Voltammetry

A simple and rapid electrochemical method for the determination of atorvastatin in pharmaceutical preparations was developed. The anodic peak at 1.07 V obtained in a buffer on glassy carbon electrode was used for analysis. The peak current and peak potential depends on pH, scan rate and initial potential. Decrease of the anodic peak with increasing pH, as well as deviations from linear plots of ip=f(C) and i=kv1/2 indicate that this peak at higher concentrations is affected by adsorption-desorption phenomena. The calibration curves were linear for atorvastatin at the concentration range of 1-50 μg/ml or square wave and differential pulse voltammetry methods, respectively. Intra and interday precision values for atorvastatin were less than 3.17, and accuracy (relative error) was better than 1.93%. The mean recovery of atorvastatin was 100.4% for pharmaceutical preparations. Limits of detection were 0.3 μg/ml and 0.2 μg/ml for square wave and differential pulse voltammetry, respectively. Developed methods in this study are accurate, precise and can be easily applied to Ator, Cholvast and Lipitor tablets as pharmaceutical preparation.