Determination of Amlodipine Besylate and Valsartan using the high performance Liquid Chromatography in their tablet form

A rapid, simple, sensitive, and selective high-performance liquid chromatography method was developed for Amlodipine Besylate and Valsartan in their pharmaceutical forms. The two drugs were separated with a short retention time, using a C18 (15 cm * 4.5 mm) as a separation column, and a mobile phase consisting of water, acetonitrile, methanol, and acetic acid [0.1M], in ratios (30:30:30:10 v/v), respectively. The pH of the mobile phase was measured to be 3.2. The separation was performed at a flow rate of 0.8 mL/min, at laboratory temperature , with an injection volume of 20 μl, and a wavelength at 234 nm. Amlodipine Besylate (AMB) was separated, with a retention time of 2.762 minutes, and valsartan (VAL), with a retention time of 4.921 minutes. The linearity range of the method for Amlodipine Besylate was (2.5 - 100) µg/ml, the limit of detection (LOD) was 0.0413, and the limit of quantitation (LOQ) was 0.1376, the mean recovery percentage was 99.09% with a correlation coefficient 0.9999 , and the relative standard deviation (%RSD) was 0.5506% . For valsartan, the linearity range of the method was (5 - 240) µg/ml, the limit of detection (LOD) was 0.1032 , the limit of quantitation ( LOQ ) was 0.3441, whether separately or together in their pharmaceutical preparations, and it was of high accuracy and consistent. So the study aimed to develop a new method for determining amlodipine, besylate, and valsartan using high performance liquid chromatography.