Analysis by capillary electrophoresis-laser-induced fluorescence detection of oligosaccharides produced from enzyme reactions.

Six structurally similar, fluorescently labeled oligosaccharides were baseline resolved by capillary electrophoresis (CE); laser induced fluorescence (LIF) detection gave detection limits of 50 molecules for the oligosaccharides. A simple design of the LIF detector that incorporates the advantages of high sensitivity, stability and ease of operation is described. The system was used to monitor enzyme products formed during the incubation of yeast cells with alpha-D-Glc(1-->2)alpha-D-Glc(1-->3)alpha-D-glc-O(CH2)8CONHCH2CH2NHCO - tetramethylrhodamine. This fluorescent trisaccharide is enzymatically hydrolyzed to fluorescent disaccharide, monosaccharide and the free linker arm that is used to conjugate the saccharides with the fluorophore tetramethylrhodamine.