FAST SEPARATION OF UNDERIVATIZED CARBOHYDRATES BY COELECTROOSMOTIC CAPILLARY ELECTROPHORESIS

A method for the rapid quantitative analysis of underivatized acidic s ugars, monosaccharides and disaccharides using coelectroosmotic capill ary electrophoresis was developed. Indirect UV detection at 254 nm usi ng sorbate as background electrolyte was employed for monitoring the a nalytes, A highly alkaline pH value of the electrolyte system was chos en in order to achieve an electrophoretic mobility of the saccharides towards the anode. A dynamic reversal of the electroosmotic flow and, by this means, a codirectional movement of the negatively charged anal ytes and the electroosmotic flow is accomplished by employing a polyca tionic surfactant (hexadimethrine bromide), which is added to the back ground electrolyte. To further improve the resolution of specific carb ohydrates, acetone is used as organic modifier. A practical applicatio n of the developed method for the fast determination of fructose, gluc ose, and sucrose in various soft drinks is provided.