Author(s): Madhuri A. Hinge*, Dipti Patel
In the present work, two different spectrophotometric methods for simultaneous estimation of Amlodipine Besylate and Candesartan Cilexetil in bulk and in formulation are described. Overlapped data(spectra) was quantitatively resolved by using two chemometric methods, Inverse least squares (ILS) and Classical least square method (CLS). The Calibration curves were plotted using the absorbance and concentration of the mixed solutions of two drugs. The drugs; Amlodipine Besylate and Candesartan Cilexetil were found to be linear in 5–15 and 8–24 µg/ml range. The data matrix of absorbance was generated by measuring the absorbance in the wavelength range from 300 to 360 nm. A Calibration set composition of the concentration of different mixture of Amlodipine Besylate and Candesartan Cilexetil was assembled in statistical way to optimize the particulate content from the spectra in way to get minimal errors in multivariate calibrations. The algorithms of CLS and ILS were applied to the spectra of the mixture of two drugs in calibration set and a suitable matrix was acquired. The model from CLS and ILS was selected by studying values of RMSEP. Then this algorithms was applied to the prediction set of different mixture of two drugs and marketed formulation. The results of recovery study of the marketed formulation were determined with great sensitivity in terms of limit of detection and limit of quantification. These CLS and ILS methods are validated and proposed methods were successfully employed for analyses of drugs in the mixtures of drugs and formulation.
