ABSTRACT
Objective:To establish an HPLC method for the simultaneous determination of olmesartan medoxomile, amlodipine be-sylate and hydrochlorothiazide in compound olmesartan medoxomile tablets. Methods:The desired chromatographic separation was a-chieved on a Phenomenex C18 (250 mm × 4. 6 mm, 5μm) column. With gradient elution, the optimized mobile phase consisted of ace-tonitrile as solvent A, and 50 mmol·L-1 potassium dihydrogen phosphate buffer (pH 3. 0, containing 0. 05% triethylamine) as sol-vent B. The flow rate was set at 1. 0 ml·min-1 , the column temperature was 30 ℃, the UV detection was carried out at 236 nm and the sample size was 20μl. Results:The compounds were separated well, the linearity between the peak area and the concentration was observed within the range of 4. 0-80. 0 mg·L-1(r=0. 999 9)for olmesartan medoxomile, 1. 0-20. 0 mg·L-1(r=0. 999 9)for amlo-dipine besylate and 1. 25-25. 0 mg·L-1(r=0. 999 9)for hydrochlorothiazide. The average recovery of olmesartan medoxomile, amlo-dipine besylate and hydrochlorothiazide was 99. 1%(RSD=1. 31%, n=9), 100. 3%(RSD=1. 21%, n=9) and 100. 2%(RSD=1. 06%, n=9), respectively. Conclusion:The method is specific and stable in the determination of olmesartan medoxomile, amlo-dipine besylate and hydrochlorothiazide in the tablets.