Development and validation of stability indicating RP-HPLC method for estimation of fluvastatin sodium in bulk and capsule dosage form

Abstract

A sensitive, specific and stability-indicating reversed phase high performance liquid chromatography-diode array detection method was developed for the quantitative determination of fluvastatin sodium in the presence of its degradation products. The chromatographic separation was performed on a Phenomenex Luna C18 column (150 X 4.0 mm, 5μm) in isocratic mode using acetonitrile and 0.02M potassium phosphate buffer (50 + 50, v/v, pH 5.0 adjusted with potassium hydroxide) as the mobile phase at a flow rate of 1.0 ml/min. The quantification was performed with a photodiode array detector at 235nm based on peak area. The method showed good linearity over the concentration range of 5-40 μg/mL with a detection limit of 1.1μg/mL and quantification limit of 3.3μg/mL. The proposed LC method was used to investigate the kinetics of acidic and oxidative degradation of fluvastatin sodium. The acidic and oxidative degradation had shown an apparent first-order kinetics and rate constants were found to be 0.0191μg/mL/min and 0.0048μg/mL/min, respectively.