RP-HPLC method for simultaneous estimation of propranolol hydrochloride and flunarizine dihydrochloride in their combined dosage formulation

Aim: A simple, precise and accurate RP-HPLC method with UV-Visible detector has been developed and subsequently validated for the simultaneous determination of propranolol hydrochloride (PRP) and flunarizine dihydrochloride (FLU) in their combined dosage formulation. Materials and Methods: The separation was based on the use of a Kromasil C8 analytical column (150 × 4.6 mm, i.d., 5 μm). The mobile phase consisted of a mixture of 70 volumes of methanol and 30 volumes of 10 mM phosphate buffer (pH 3.8). The separation was carried out at 40°C temperature with a flow rate of 0.8 ml/ min. Result and Conclusion: Quantitation was achieved with UV detection at 242 nm, with linear calibration curves at concentration ranges of 32-72 μg/ml for PRP and 8-18 μg/ml for FLU. The recoveries obtained were 98.97-101.10% and 98.86-102.27% for PRP and FLU, respectively. The method was validated according to the ICH guidelines in terms of linearity, accuracy, precision, specificity, robustness, limits of detection, limit of quantitation, and system suitability of analytical method validation.