Determination of etofibrate, fenofibrate, and atorvastatin in pharmaceutical preparations and plasma using differential pulse polarographic and square wave voltammetric techniques.

Etofibrate, fenofibrate, and atorvastatin were determined in their pharmaceutical preparations and human plasma using differential pulse polarographic and square wave voltammetric techniques by reduction at a dropping-mercury working electrode versus Ag/AgCl reference electrode. The reversibility of the electrode reactions was tested using cyclic voltammetry, and they were found to be irreversible reduction reactions. Optimum conditions such as pH, scan rate, and pulse amplitude were studied, and validation of the proposed methods was performed. The proposed methods proved to be accurate, precise, robust, and specific for determination of the 3 drugs. The relative standard deviation values were <2%, indicating that these methods are precise. Limits of detection and quantitation were in the ranges of 0.037-0.21 and 0.12-0.71 microg/mL, respectively, indicating high sensitivity.