Spectrophotometric method is described for the simultaneous determination of binary mixtures of eosin and erythrosine in pharmaceutical and food samples, without prior separation steps, using mean centering of ratio spectra. The method is based on the difference in the absorption spectra for the products of the reaction of eosin and erythrosine with Cr(VI) in the presence of CPB micellar media at pH 6.0. The method allows rapid and accurate determination of eosin and erythrosine. The results showed that the method was capable to simultaneous determination of 1.24-6.86 µg/mL and 1.47- 8.06 µg/mL each of eosin and erythrosine. The proposed method was successfully applied to the simultaneous determination of eosin and erythrosine in pharmaceutical and food samples.
Eosin, Erythrosine, Cr(VI), CPB, Mean Centering of ratio spectra