Abstract
A simple, precise, sensitive and specific liquid chromatographic method was developed for the simultaneous estimation of olmesartan medoxomil (OLM), amlodipine besylate (AMLO) and hydrochlorothiazide (HCTZ) in tablet dosage form. Separation was achieved with Purospher ®-STAR, RP-C18, 5μ, 250 mm x 4.6 mm column, using simple isocratic mode with mobile phase containing acetonitrile: potassium dihydrogen orthophosphate buffer adjusted to pH 3.0 with orthophosphoric acid (48: 52 v/v). The flow rate for analysis was 1.0 mL/min andUV detection at 238nm for hydrochlorothiazide, amlodipine besylate and olmesartan medoxomil. The selected chromatographic conditions effectively separated hydrochlorothiazide, amlodipine besylate and olmesartan medoxomil with retention time of 3.3, 3.9 and 7.7 minutes, respectively. Percent release for all three drugs achieved in dissolution study was more than 92% of labeled amount upto 60 min under optimized dissolution conditions. The HPLC method and dissolution method were validated with respect to system suitability, specificity, linearity, precision, accuracy and robustness.The results of the method were acceptable confirming that these methods can be applicable, without any interference from the excipients. In conclusion, a novel, simple, accurate and reproducible high performance liquid chromatographic method was developed and can be useful in routine quality control, dissolution study and pharmaceutical dosage form analysis.
