Continuous wavelet transform applied to the simultaneous spectrophotometric determination of valsartan and amlodipine in tablets

Abstract

A new signal procesing approach based on continuous wavelet transform (CWT) was proposed for the simultaneous spcetroptometric determination of valsartan and amlodipine in tablets without making use of any chemical separation procedure. After the CWT method was applied to the analyzed spectra, the results were plotted in wavelet domain. Several CWT families were tested and Daubechie10 (db10-CWT) and DMeyer (dmey-CWT) were found suitable for the determination of VAL and AML. The procedure of the selection of CWT family was based on the recovery results of signal analysis. Calibration graphs obtained by the linear regression analysis were performed by measuring the CWT amplitudes at 258.5 and 263.3 nm for VAL by using dmey-CWT and db10-CWT and at 265.7 and 270 nm for AML by using dmey-CWT and db10-CWT respectively. Linear calibration ranges were considered as 2-42 mu g/mL for VAL and 2-32 mu g/mL for AML respectively. The validation treatments for the proposed CWT methods were performed by analyzing various synthetic mixtures and by using the standard addition technique. Successful determination results were obtained by applying db10-CWT and dmey-CWT methods to the tablet analysis