IMPROVEMENT IN THE DETERMINATION OF FOOD ADDITIVE DYESTUFFS BY CAPILLARY ELECTROPHORESIS USING BETA-CYCLODEXTRIN

The determination of seven food additive dyestuffs was investigated by capillary electrophoresis. When beta-cyclodextrin was introduced into the carrier electrolyte, the apparent mobility was increased, leading to 9.5-39% lower migration times due to the increase in the solute's mass after inclusion complex formation. The reproducibility and peak s hape were improved because interaction between the solute and the capi llary wall was alleviated. The effects of beta-cyclodextrin on the mig ration time, elution order, peak shape and reproducibility of food add itive dyestuffs are discussed in terms of providing a considerable adv antage for determining organic anions by capillary electrophoresis. Se quential injection of dyestuffs and beta-cyclodextrin into a capillary electrophoresis column was found to be a simple and rapid method for a qualitative comparative study of inclusion complexation phenomena.