CAPILLARY ELECTROPHORESIS OF ANTHRAQUINON E PIGMENTS FOR FOOD

Capillary electrophoretic methods have been developed for analysis of the natural anthraquinone pigments (lac and cochineal pigments) for fo od. Lac and cochineal pigments were not separated by capillary zone el ectrophoresis (CZE) using 50 mM phosphate buffer nor by micellar elect rokinetic chromatography (MEKC) with 20 mM sodium dodecylsulfate. The pigments were successfully separated by MEKC with 2% butyl acrylate-bu tyl methacrylate-methacrylic acid copolymer sodium salts (BBMA). Howev er, this method did not give reproducible results on repeated runs. Ad dition of 1 mM EDTA to the BBMA solution improved the reproducibility. The lac and cochineal pigments extracted from foods (juice and jelly) with solid phase extraction cartridges were analyzed by the developed technique.