Simultaneous Determination of Amlodipine Besylate and Valsartan in Tablets by High Performance Liquid Chromatography with UV Detection

A simple, precise, accurate and sensitive high-performance liquid chromatography method with uv detection at 220 nm was developed for the simultaneous determination of amlodipine and valsartan drugs in pharmaceutical formulations. the present method presents a narrow range (19.6-78.4 (for amlodipine) and 32-128 (for valsartan) ƒêg/ml) of calibration curve and sensitivity. isocratic separation was employed on a c18 column (250*4.6 mm i.d., 5 μm) at ambient temperature. the mobile phase consisted of water, acetonitrile and glacial acetic acid (300:700:1 by volume). the drugs under investigation were found to be 93.101% recovery of their label claim in pharmaceutical formulations. the separation was completed within 6 minutes. the calibration curve was linear over the range of 19.6.78.4 μg/ml for amlodipine and over the range of 32 to 128 μg/ml for valsartan. the limits of quantification (loq) were chosen to be the lowest concentrations in the calibration curve (19.6 μg/ml) for amlodipine and (32 μg/ml) for valsartan. the limits of detection (lod) were 10 μg/ml and 16 μg/ml for amlodipine and valsartan, respectively. good method precision was demonstrated for the analysis with a coefficient of variation of 0.0049 and 0.002 for amlodipine and valsartan, respectively).