RP-HPLC METHOD FOR SIMULTATANEOUS DETERMINATION OF ATORVASTATIN CALCIUM, OLMESARTAN MEDOXOMIL, CANDESARTAN, HYDROCHLOROTHIAZIDE AND CHLORTHALIDONE – APPLICATION TO COMMERCIALLY AVAILABLE DRUG PRODUCTS

A simple, precise and stability-indicating HPLC method was developed and validated for the simultaneous determination of anti-hypertensive drugs Atorvastatin Calcium, Olmesartan Medoxomil, Candesartan, diuretics Hydrochlorothiazide and Chlorthalidone. The separation was achieved on Cosmosil PAQ (Length 150 mm × Diameter 4.6 mm Particle size 5 μm) column with gradient flow. The mobile phase at a flow rate of 1.0 mL min 1 consisted of 0.05 M sodium dihydrogen phosphate buffer and acetonitrile (Gradient ratio). The UV detection was carried out at 220 nm. The method was successfully validated in accordance to ICH guidelines. Further, the validated method was applied for commercially available pharmaceutical dosage form.