Simultaneous Estimation of Aspirin and Atorvastatin Calcium in Capsule Dosage Form by Spectrophotometric Method

A simple, precise and economical procedure for the simultaneous estimation of Aspirin and Atorvastatin Calcium in capsule formulation has been developed. The first method employs simultaneous equations (Method I) which involve absorbance measurement at 225.5 nm (λ max of Aspirin) and 246.0 (λ max of Atorvastatin Calcium). Second method involves absorbance ratio (Method II), which uses the ratio of absorbances measured at two selected wavelengths, one at isoabsorptive point (232.5 nm) and other being the max of one of the two compounds. Third method involves measurement of area under curve (AUC). For this method wavelength ranges were chosen between 223.5-227.5 nm and 244-248 nm for Aspirin and Atorvastatin Calcium respectively. Results of analysis for methods were tested and validated for various parameters according to ICH guidelines, hence can be adopted for the routine analysis of Aspirin and Atorvastatin Calcium in tablet dosage form.