A Comprehensive Validation Method and Development of RP-HPLC for Simultaneous Estimation of Metoprolol, Telmisartan and Chlorthalidonein Bulk and its Formulation

Thepresent research work was aimed to develop a simple, precise, sensitive and reliable, gradient RP-HPLC method and to comprehensively validate as per the guidelines given under ICH Q2(R1) for simultaneous estimation of Metoprolol, Telmisartan and Chlorthalidone in their combined dosage form. A thorough computer assisted literature survey revealed that there is no HPLC method for aforementioned drugs. A new combination of Metoprolol, Telmisartan and Chlorthalidone is available in market as Met XL 3D and it is found to beneficial in the treatment of hypertension. HPLC separation was achieved by using Phenomenex C18 column (250×4.5mm, 5μ) with phosphate buffer (pH adjusted to 3.0): acetonitrile as mobile phase in gradient mode at a flow rate of 1ml/min and UV detection at 310 nm. Retention times were found to be 4.5, 7.2 and 11.01min for Metoprolol, Telmisartan and Chlorthalidone respectively. The drugs are found to be linear with correlation coefficient value was nearly 0.999. Percentage recoveries from recovery studies were found to be 99.22, 99.17 and 99.02% for Metoprolol, Telmisartan and Chlorthalidone individually. LOD and LOQ were found to be lower, hence the method is sensitive.