SIMULTANEOUS DETERMINATION OF TARTRAZINE AND BRILLIANT BLUE IN COSMETIC PRODUCTS BY FIRST-DERIVATIVE SPECTROPHOTOMETRY

A new method for simultaneous determination of tartrazine (TT) and bri lliant blue FCF (BE), two synthetic colouring materials present in cos metic products, is proposed. The colourings were extracted from a mixt ure EtOH/H2O (70:30 v/v) using methylene chloride and their absorbance s were measured directly in the aqueous phase formed. The applicable c oncentration ranges were 0.5-10.0 mu g ml(-1) for tartrazine and 0.5-4 .0 mu g ml(-1) for brilliant blue FCF. Relative standard deviations (R SD) and detection limits were 0.9% and 0.8% and 19 ng ml(-1) and 7 ng ml(-1) for TT and BE respectively. The method was applied to determina tion of both compounds in colognes.