9 research outputs found
RP-LC and HPTLC Methods for the Determination of Olmesartan Medoxomil and Hydrochlorothiazide in Combined Tablet Dosage Forms
Two new, rapid, precise, accurate and specific chromatographic methods were described for the simultaneous determination of olmesartan medoxomil and hydrochlorothiazide in combined tablet dosage forms. The first method was based on reversed phase liquid chromatography using an Eurosphere 100 RP C18 column (250Â ĂÂ 4.6Â mm ID, 5Â ÎŒm). The mobile phase was methanolâ0.05% o-phosphoric acid (60:40 v/v) at a flow rate of 1.0Â mLÂ minâ1. Commercially available tablets and laboratory mixtures containing both drugs were assayed and detected using a UV detector at 270Â nm. The second method involved silica gel 60 F254 high performance thin layer chromatography and densitometric detection at 254Â nm using acetonitrileâethyl acetateâglacial acid (7:3:0.4 v/v/v) as the mobile phase. Calibration curves ranged between 200â600 and 125â375Â ng spotâ1 for olmesartan and hydrochlorothiazide, respectively