SIMULTANEOUS DETERMINATION OF SIMVASTATIN AND EZETIMIBE IN
PHARMACEUTICAL FORMULATION USING HIGH PERFORMANCE LIQUID
CHROMATOGRAPHIC, SPECTROPHOTOMETRIC AND CHEMOMETRIC-ASSISTED
SPECTROPHOTOMETRIC METHODS
Hesham Salem, Sara Salah, Siola Samir, Mohammed Abdullah and Nader Sharaf Eldin
Five methods were developed for simultaneous determination of Simvastatin and Ezetimibe without previous separation. In the first method (HPLC), a reversed-phase column was used to separate both drugs. In the second method both drugs were determined using first derivative UV spectrophotometry, with zero crossing measurement. The third one depend on isosbestic points. The fourth method describes the use of multivariate spectrophotometric calibration for the simultaneous determination of the analyzed binary mixture where the resolution is accomplished by using classical least squares (CLS) regression analysis. Although the components show high degree of spectral overlap, they were simultaneously determined with high accuracy and without interference of pharmaceutical dosage form excipients. All the proposed methods were extensively validated. They have the advantage of being economic and time saving. All the described methods can be readily utilized for the analysis of pharmaceutical formulations. The results obtained by adopting the proposed methods were statistically analyzed and compared with those obtained by official methods.
Keywords: Simvastatin, Ezetimibe, HPLC, First derivative spectrophotometry, Isosbestic point, Multivariate and pharmaceutical dosage form.