Discrete and continuous wavelet transforms for the multicomponent determination of sunset Yellow and tartrazine in their soft drink powders

Abstract

The multicomponent quantitative resolution of the binary mixtures containing, sunset Yellow (SN) and tartrazine (TR) without any pre-chemical treatment, in the presence of the overlapping signals was accomplished by the simultaneous use of the discrete and the continuous wavelet transform (CWT) followed by a zero crossing technique. We propose G transformation approach of signals in wavelet domain, based on both one-dimensional CWT and zero-crossing technique for obtaining a higher resolution of the binary mixtures. The application of this approach contains three steps: firstly, UV-recorded spectra were transferred into the wavelet domain and were subject to the one-dimensional discrete wavelet transform for obtaining an appropriated de-noising signal; secondly, CWT was applied on the de-noising signal and a new transformed signal was obtained so that it contains many zero-crossing points and higher peaks.; thirdly, a zero-crossing technique was applied to the transformed signal obtained in step two, The calibration graphs were drawn by choosing a one-dimensional continuous family, namely, Symlets2 (SYM2) and Gauss3 (GAUS3) followed by a zero-crossing technique. The quantitative analysis of the commercial product containing the above colorants was carried out by using this approach and successful results were obtained.