The Resolution of Dye Binary Mixtures by Bivariate Calibration Using Spectrophotometric Data

A new, simple spectrophotometric method for resolution of dye binary mixtures is proposed in this work. A simple mathematical algorithm was designed, in which the data are used from four linear regression calibration equations: two calibrations for each component at two selected wavelengths. The method of Kaiser was applied for the selection of the optimum two-wavelength sets for all mixtures under study. The recovery experiments were carried out in ten mixtures of the following dyes: Tartrazine, Amaranth, Erythrosin B, Sunset Yellow and Allura Red. The obtained results were compared with the results of a commonly used derivative spectrophotometric procedure (zero-crossing technique). The statistical evaluation of the method bias was performed and it was concluded that the proposed methodology may be competitive with the derivative procedure for the resolution of such dye binary mixtures.