Development and Validation of UV-Derivative Spectroscopic and RP-HPLC Methods for the Determination of Amlodipine Besylate and Valsartan in Tablet Dosage form and Comparison of the Developed Methods by Student’s T-Test

Introduction: Hypertension is directly responsible for 51% of all stroke deaths and 45% of all coronary heart diseases worldwide. Amlodipine besylate is a calcium channel blocker used as an anti-hypertensive agent. Valsartan is an angiotensin II receptor blocker used in the treatment of hypertension. Rationale: Fixed-dose combination products are becoming popular because of simplified dosage regimens, enhanced patient adherence and reduced costs. Therefore there is a need for analytical methods for consistent quality establishment throughout the shelf life of the product. Objective: To develop and validate UV derivative spectrophotometric and RP-HPLC methods for the simultaneous determination of Amlodipine besylate and Valsartan in tablet dosage form. To compare the developed methods by student’s t-test for their suitability and sensitivity in routine quality control. Methods: For the simultaneous estimation of Amlodipine besylate and Valsartan, first, second and third order derivatization was carried out in Agilent Cary 60 UV/Vis double beam spectrophotometer. HPLC method was carried out by using Agilent 1220 Infinity LC equipped with Eclipse XDB plus C18 Column (4.6 × 150 mm, 5 μm) with a mobile phase consisting of a mixture Methanol and Acetonitrile in the ratio of 70:30 % v/v at a flow rate of 1 ml/min. Results: The developed methods were validated as per ICH guidelines in terms of accuracy, precision, LOD and LOQ. The proposed methods were found to be suitable for simultaneous determination of Amlodipine Besylate and Valsartan in bulk and in pharmaceutical dosage forms. The results of the developed methods were then compared by student’s t test. Conclusion: The developed methods were found to be simple, accurate, precise and rapid for simultaneous estimation of the selected drugs. The null hypothesis from student’s t-test was found to be acceptable indicating no significant difference between the results of the proposed methods. Hence depending on the availability of instruments and reagents any of the proposed methods can effectively be applied for the routine analysis of Amlodipine besylate and Valsartan in bulk and in combined pharmaceutical dosage forms..