Simultaneous Estimation of Aspirin, Atorvastatin Calcium and Clopidogrel Bisulphate in a Combined Dosage form by RP-HPLC

A rugged robust RP-HPLC method has been developed and validated for the simultaneous quantification of Aspirin (ASP), Atorvastatin calcium (ATO) and Clopidogrel bisulphate (CLO) in a combined dosage form. Optimized mobile phase composition of 25 mM KH2PO4: Methanol (20:80% v/v) pH 3.0 (adjusted with 20% o-phosphoric acid) isocratic mode with flow rate of 1 ml min-1, detection at 230 nm. Employed Princeton SPHER C18 (150 x 4.6 mm i.d. 5 µm) column for separation at ambient temperature with an isocratic flow. The linearity of each drug across the range of 0.5-32 µg/ml with correlation coefficient for ASP, ATO, and CLO in value of 0.979, 0.988 and 0.989 respectively. The retention time (min.) for ASP, ATO and CLO were found 1.85, 3.04 and 6.91 respectively. Limit of detection (LOD) of ASP, ATO and CLO - 0.04, 0.04, 0.08 (μg ml-1) respectively and Limit of Quantification (LOQ) of ASP, ATO and CLO- 0.14, 0.13, 0.28 (μg ml-1) in order. Performed analysis of marketed tablet formulation ASP (Ecosprin-75 mg), ATO (Aztor®40- 40 mg), CLO (Clopivas- 75 mg) found percentage recovery for ASP (99.93), ATO (100.00) and CLO (99.87). Performed stability studies found satisfactory results. Developed method has been validated, results of different parameter found in acceptable range. Chromatogram peaks are resolve, symmetric shape and without interference.