Separation of aminated monosaccharides by capillary zone electrophoresis with laser-induced fluorescence detection

The six most abundant hexoses found in mammalian carbohydrates were derivatized to serve as standards for an oligosaccharide sequencing project. Glucose, galactose, mannose, and fucose were reductively aminated to produce 1-amino-1-deoxy alditols. Standards for N-acetylglucosamine and N-acetylgalactosamine were synthesized by reducing glucosamine and galactosamine to 2-amino-2-deoxy alditols. The monosaccharides were labeled with 5-carboxytetramethylrhodamine succinimidyl ester. By carefully adjusting the separation buffer, we have separated the sugar derivatives completely. The detection limit is 100 molecules of labeled sugar with a post-column laser-induced fluorescence detection in a sheath flow cuvette.