Simultaneous Estimation of Antihypertensive and Antidiabetic Drugs by HPLC
A simple, fast and economic reversed phase high performance liquid chromatographic (HPLC) method has been successfully developed and validated for simultaneous determination of an antihypertensive and an antidiabetic drug namely, valsartan and glimepiride in pure form (as API). Before the method development with HPLC, a complexation study was carried out with these drugs by DSC which demonstrated no complexation among these drugs. Therefore, a simple HPLC method was developed and validated according to the guidelines of ICH, FDA and USP with respect to accuracy, precision and linearity. For method development a C-18 bonded silica column (250 x 4.6 mm, 5μ, Phenomenex, Inc.) and the mobile phase comprising 3% aqueous acetic acid in acetonitrile (60:40, v/v) at a flow rate of 0.7 ml/min were used. For accuracy, the recovery was found to be more than 99% for each of valsartan and glimepiride. Intra-day and inter-day precisions of the new method were less than the maximum allowable limit (RSD%ï£ 2.0) according to FDA guidelines. The method showed linear response with correlation coefficient of 0.9993 for valsartan and 0.9981 for glimepiride. Therefore, the developed method was found to be simpler, accurate, reproducible, efficient and less time consuming and can be successfully applied for the simultaneous estimation of valsartan and glimepiride.
Mohammad Farhadur Rahman, Md. Zakir Sultan, Asma Rahman, Md. Anisur Rahman and Md. Abdus Salam