MULTIDIMENSIONAL MAPPING OF PYRIDYLAMINE-LABELED N-LINKED OLIGOSACCHARIDES BY CAPILLARY ELECTROPHORESIS

A simple, sensitive and reproducible multi-dimensional capillary elect rophoresis (CE) oligosaccharide mapping method is reported. The struct ures of 20 identified N-linked oligosaccharides have been assigned map ping positions from which co-migrating unknown oligosaccharides can be characterized. The separation protocols developed have been demonstra ted to separate both charged and neutral oligosaccharides. One dimensi on involves electroendosmotic flow-assisted CE in a sodium acetate buf fer, pH 4.0. A second dimension involves separation based on berate co mplexation electrophoresis in a polyethylene glycol-containing buffer. A third dimension developed specifically for neutral oligosaccharides , using a sodium phosphate buffer, pH 2.5, has been shown to resolve n eutral species not able to be separated by the other two dimensions. T hus, a three-dimensional map was generated to facilitate structural ch aracterization of these oligosaccharides.