DETERMINATION OF SYNTHETIC COLORANT FOOD-ADDITIVES BY CAPILLARY ZONE ELECTROPHORESIS

A capillary zone electrophoresis method for the separation of six synt hetic food colourants is proposed. A background electrolyte solution c onsisting of 20 mM berate buffer adjusted to pH 7-9 and electromigrati on injection at 4 kV for 14 s were utilized. A baseline separation of six synthetic colourants commonly used as food additives can be achiev ed within 10 min, and a linear relationship between the concentration and peak area for each of these pigments was obtained in the concentra tion range 2-50 ppm, with a correlation coefficient greater than 0.995 . The selection of the analytical conditions and the experimental repr oducibility are discussed.