ANALYTICAL METHOD DEVELOPMENT FOR ESTIMATION OF S (-) AMLODIPINE BESYLATE & OLMESARTAN MEDOXOMIL BY UV SPECTROSCOPY
For simultaneous estimation of S (-) amlodipine besylate & olmesartan medoxomil, the simple, accurate, precise, reproducible and economic UV spectroscopic methods have been developed. The method A-Area Under curve method, method B- Absorption ratio method and method C- Dual wavelength method were developed by using JASCO double beam UV Spectrophotometer (model-V630). Simultaneous estimation of S(-) amlodipine Besylate and olmesartan medoxomil was carried out at wavelength 238 nm and 257 nm respectively. Both the drugs were showing linearity at 238 nm and 257 nm and obey Beer’s law in the concentration range of 5-20µg/ml with good correlation coefficient. In Area under curve method, wavelength selected for S (-) amlodipine besylate was from 227 to 249 nm and for olmesartan medoxomil was from 244 to 269 nm.It gives peak area of 1.9585 for S (-) amlodipine besylate and 2.1252 for Olmesartan medoxomil. Absorption ratio method involves formation of isoabsorptive point at 237 nm