SPECTROPHOTOMETRIC AND STABILITY INDICATING RP-HPLC METHOD FOR ESTIMATION OF RANOLAZINE IN TABLET DOSAGE FORM

A spectrophotometric and reverse phase high performance liquid chromatography methods has been developed for the estimation of Ranolazine in bulk and pharmaceutical dosage form. For UV spectrophotometric method Ranolazine shows maximum absorbance at 273 nm with the concentration ranges of 20-150 µg/mL. The detection limit and quantification limit were found to be 1.23 and 5.21 µg/mL, respectively. Accuracy was in the range of 99.8-100.2%. Intraday and interday precision was in the range 0.16- 0.38% and 0.50-0.82% respectively. The RP-HPLC separation was achieved by using Phenomenex Gemini C₁₈ (100mm X 4.6mm), 3μm column and buffer: acetonitrile (60:40, v/v), (1.0 mL of triethylamine in 1000 mL milli- Q water, pH adjusted to 6 using dilute o-phosphoric acid solution) as mobile phase. The flow rate was 1.0 mL/min and effluents were monitored at 224 nm. The retention time was 5.08 min. The linearity was in the range of 20-150 µg/mL. The detection limit and quantification limit were found to be 1 and 4 µg/mL, respectively. Accuracy was in the range of 99.9-100.1%. Intraday and interday precision was in the range 0.29- 0.75% and 0.51-0.95% respectively. Ranolazine were subjected to acidic, alkali, oxidative, photolytic and dry heat degradation. The degraded product peaks were well resolved from the pure drug peak. The proposed methods were validated and successfully applied to the estimation of Ranolazine in tablet formulation.