Manipulation of different ratio dependent approaches for determination of pravastatin in the presence of pioglitazone in pharmaceutical preparation

Abstract

Objective: This study aimed to develop three simple UV spectrophotometric methods for determination of pravastatin sodium in the presence of pioglitazone hydrochloride without previous separation. Methods: Ratio spectra were developed for the interested methods. The first method is the ratio subtraction using 16µg/mL of pioglitazone hydrochloride as a divisor. The second method is an amplitude modulation using the normalized spectrum of pioglitazone hydrochloride as a divisor (1µg/mL) the peak amplitudes of ratio spectra were measured at isoabsorptivity point 251.4nm. The third method is the ratio difference using 14µg/mL of pioglitazone hydrochloride as a divisor, where the peak amplitudes of ratio spectra were measured at 240 and 246.4nm. Results and discussion: The calibration curve is linear over the concentration range of 2-20µg/mL, the proposed methods were validated according to International Conference on Harmonization (ICH) guidelines and successfully applied for the determination of pravastatin sodium in the presence of pioglitazone hydrochloride in their combined pharmaceutical formulation, Pravazon® capsules with high sensitivity. Conclusion: The proposed three methods are simple, rapid, economical, accurate and precise for determination of pravastatin sodium in the presence of pioglitazone hydrochloride without previous separation.