A Stability Indicating ultra Performance Liquid Chromatography Method for Simultaneous Estimation of Verapamil Hydrochloride and Trandolapril in Combined Dosage Formulations

An accurate, rapid, specific and stability indicating ultra performance liquid chromatographic method was developed and validated for the simultaneous estimation of Verapamil and Trandolapril in a combined pharmaceutical dosage form. The chromatographic separation was attained on Phenonemex Luna C18 (4.0 x 100 mm, 2.6mm) column by isocratic mode with the mobile phase components as 0.03M monobasic potassium phosphate buffer (pH6.5) and acetonitrile (70: 30v/v) at a flow rate of 1.0 mL/min and quantified at 210 nm. The average retention times for Trandolapril and Verapamil were 0.60 and 1.14 min, respectively. The UPLC method proposesoutstanding separation of two drugs with a good resolution of greater than 2.0 and tailing factor less than 2.0 with a run time of 3 minutes. The method shows linearity over the concentration range of 9-45 µg/mL for Verapamil and 0.1-0.5 µg/mL for Trandolapril with a correlation ≥ 0.999. The method is accurate with recoveries in the range of 98.0 -101.0% and precise with %RSD value lesser than2.0% for both the drugs. This method is very fast, cost saving, accurate and specific for the assay of commercially available tablets.