Document Type : Original Article
Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Al-Azhar University,11751, Nasr City, Cairo, Egypt.
Three simple, accurate and precise multivariate calibration models, including classical least square (CLS), principal component regression (PCR) and partial least square (PLS-1), have been used for simultaneous determination of the components of recently approved fixed – dose combination tablet containing amlodipine / candesartan mixture in their pure forms and their pharmaceutical preparations, using spectral data in the range of (220nm-400nm). The CLS, PCR and PLS-1 models are useful in spectral analysis because the simultaneous employment of many spectral wavelengths instead of the single wavelength used in derivative spectrophotometry, which greatly improves the precision and predictive abilities of these multivariate calibrations. The developed methods were statistically compared with the reported spectrophotometric method and no significant differences were observed regarding both accuracy and precision, all the developed methods have been validated using external validation set. Moreover, the proposed models were successfully applied to the spectrophotometric determination of amolodipine besylate and candesartane cilexetil in Unisia® tablets.