SPECTROPHOTOMETRIC DETERMINATION OF ATORVASTATIN CALCIUM AND VALSARTAN IN BULK AND TABLET DOSAGE FORMS USING 1,2-NAPHTHOQUINON-4-SULPHONATE

A simple and sensitive spectrophotometric method is described for determination of atorvastatin calcium and valsartan in bulk and tablet forms. The method is based on the formation of colored chromogen between atorvastatin calcium or valsartan and 1,2-naphthoquinon-4-sulphonate (NQS) and the reaction mixture exhibits maximum absorbance at λ max 464 and 466 nm for atorvastatin calcium and valsartan, respectively. Under the indicated conditions, this method was linear over the concentration range of 2-14 μg/mL and 10-120 μg/mL for atorvastatin calcium and valsartan, respectively. The results were statistically processed to evaluate the method for determining the drugs in both bulk and tablet forms. Results were compared with reference methods, and no significant difference was obtained. The proposed method was validated in terms of linearity, accuracy, precision and limits of detection and quantitation according to ICH.