Development of Electrochemical Methods for Determination of Atorvastatin and Analytical Application to Pharmaceutical Products and Spiked Human Plasma

Abstract

Atorvastatin is a new synthetic inhibitor of HMG-CoA reductase that has been recently and intensively prescribed as an antihyperlipoproteinemic drug. The property was exploited in developing a highly sensitive stripping voltammetric procedure for the determination of the drug. The anodic current of adsorbed compound is measured by differential pulse and Osteryoung square wave adsorptive stripping voltammetry, preceded by a period of preconcentration. The effect of various parameters such as supporting electrolyte composition, pH, initial potential, scan rate, accumulation time, and ionic strength are discussed to characterize the interfacial and redox behavior. The methods were performed in Britton-Robinson buffer, and the corresponding calibration graphs were constructed and statistical parameters evaluated. Applying the differential pulse adsorptive stripping voltammetry and Osteryoung square wave adsorptive stripping voltammetric method at pH 2.0 linearity was achieved from 3.5 × 10⁻⁸ to 4.6 × 10⁻⁷ M for square wave adsorptive stripping voltammetry with limit detection and limit quantitation of 4.0 × 10⁻⁹ M, 2.0 × 10⁻⁹ M and 1.0 × 10⁻⁸ M, 2.0 × 10⁻⁸ M, respectively. Since the proposed methods enabled lower concentrations of atorvastatin to be determined, this method was tested for atorvastatin determination in pharmaceutical products and spiked human plasma.

Keywords:

• atorvastatin
• differential pulse adsorptive stripping voltammetry
• Osteryoung square wave adsorptive stripping voltammetry
• pharmaceutical product
• spiked human plasma

Acknowledgments

The author gratefully acknowledges Sanovel Pharm. Company, Istanbul, Turkey, for providing the reference substance and its pharmaceutical formulations.

Notes

^a Y = a + bC where C is concentration in M and Y in peak current units for voltammetric methods.

^a ATOR tablets were labeled to contain 20.0 mg atorvastatin per tablet.

^b Each value is the mean of 10 experiments.

^c RSD = Relative standard deviation.

^d Values in parentheses are the theoretical values at p = 0.95. Theoretical values at 0.95% confidence limits; t = 2.26.

^a x, mean; RSD, relative standard deviation; SE, standard error.