A NOVEL METHOD FOR CLEANUP OF COAL-TAR DY ES USING A QUATERNARY AMINECARTRIDGE

A simple, rapid, and reliable clean-up method has been developed for i dentification of the 12 coal tar dyes permitted in Japan by using a qu aternary amine cartridge. The dyes were directly extracted from a samp le with an appropriate solvent such as water, ethanol, and ammoniacal ethanol without elimination of fat contained in the sample. The extrac t was directly applied to a Sep-pak QMA cartridge without pH adjustmen t or elimination of ethanol. The dyes retained on the cartridge were e luted with 3% hydrochloric methanol solution and the eluate was analyz ed by high performance liquid chromatography and thin layer chromatogr aphy after neutralization of the eluate with aqueous ammonia. Recoveri es of the 12 permitted coal tar dyes from white chocolate fortified at levels of 5 ppm and 10 ppm were 86.8 approximately 97.9% and 83.3 app roximately 95.6%, respectively.