HPLC determination of the dissolution of compound amlodipine,valsartan and hydrochlorothiazide tablets

Objective: To establish an optimized HPLC method to determine the dissolution of compound amlodipine,valsartan and hydrochlorothiazide tablets and simultaneously determine the dissolution of three components amlodipine,valsartan and hydrochlorothiazide. Methods: The method was carried on the Zorbax SB-C18( 3. 0 mm ×150 mm,5 μm) column,using gradient elution of the mobile phase of water containing 0. 1% triethylamine( p H2. 8),methanol and acetonitrile. The flow rate was 0. 8 m L·min-1at the detection wavelength of 230 nm. Results:The method was of good system suitability and the three components were separated completely. The blank excipients and degradation products did not interfere with the determination of the three components. The linearity and range were 2. 8-17. 3 μg·m L-1( r2= 0. 999 9) for amlodipine,32. 0-200. 2 μg·m L-1( r2= 0. 999 4) for valsartan,and 2. 5-15. 6 μg·m L-1( r2= 0. 999 6) for hydrochlorothiazide. The average recoveries( n = 9) of amlodipine,valsartan and hydrochlorothiazide were 100. 6%( RSD = 1. 1%),100. 8%( RSD = 0. 62%) and 101. 0%( RSD= 0. 70%); LOQs were 0. 33,0. 13 and 0. 12 μg·m L-1; LODs were 0. 10,0. 03 and 0. 03 μg·m L-1,respectively. The solution was stable within 72 h with good durability. The dissolutions were 92%,94% and 91% of labeled amount for amlodipine,valsartan and hydrochlorothiazide by the method. Conclusion: The method is suitable to determine the dissolution of compound amlodipine,valsartan and hydrochlorothiazide tablets.