Determination of dyes in foodstuffs by capillary zone electrophoresis

A rapid method based on capillary zone electrophoresis coupled with photodiode-array detection has been developed to determine the dyes Tartrazine E-102, Sunset Yellow FCF E110, Amaranth E-123, New Coccine E-124, Patent Blue V calcium salt E-131 and Allura Red AC E-129 in foodstuffs. Separation was done by using a Bare CElect-FS75 CE column, using a 10 mM phosphate buffer at pH 11.0. Hydrodynamic injections at 0.5 p.s.i. for 4 s (21 nl of sample) and 20 bV separation voltage were used. The quantitation limits for the six dyes ranged from 3 to 6 mug/ml. A linear relationship between 3 to 95 mug/ml, with correlation coefficient better than 0.995 was obtained. This method has been applied to the determination of the studied dyes in beverages, jellies and syrups. (C) 2000 Elsevier Science B.V. All rights reserved.