| Studies were undertaken to gain insight into the chemical structure of dermatan sulfate (DS) through the preparation and structural characterization of homogenous dermatan sulfate oligosaccharides. Oligosaccharides were prepared by partial, controlled, enzymatic digestion with chondroitin ABC lyase and their structures were determined by using strong anion exchange high performance liquid chromatography, capillary electrophoresis, electrospray ionization mass spectrometry, and 1D and 2D nuclear magnetic resonance spectroscopy.; A yeast-derived phosphomannan mixture was chemically sulfonated, affording phosphosulfomannan mixture, PI-88. Phosphosulfomannan components of PI-88 were obtained that differed in size from disaccharide to hexasaccharide, and in degree of sulfation. These fractions were characterized by chromatographic, electrophoretic and spectroscopic methods. The anticoagulant activities of PI-88 and its subfractions were investigated, and the structure-activity relationship established.; As part of our laboratory's ongoing research for improved methods for the analysis of bioactive sulfated carbohydrates, we undertook to systematically explore the application of ammonium, phosphonium, and basic peptide counter-ions in ESI-MS analysis. Sucrose octasulfate was chosen in this study as a model carbohydrate since it had an exceedingly high degree of sulfation. ESI-MS analysis was performed on each sample in the negative-ion and positive-ion modes. The positive-ion mode of analysis gave better sensitivity and less fragmentation in every salt form. The ideal counter-ion in these analyses appeared to be tetraethylammonium, with other quaternary ammonium and phosphonium salts also performing well. This work presents the first example of positive-ion ESI-MS spectra in the analysis of sulfated carbohydrates.; A capillary electrophoresis method for the separation of high molecular weight heparin oligosaccharides compatible with mass spectral detection was developed. To optimize the conditions, the coinjection of structurally defined homogenous fully sulfated heparin oligosaccharides ranging in size from tetra to tetradecasaccharide was used. Ammonium bicarbonate (30 mM, pH 8.50) running electrolyte gave good separation efficiency and resolution in the normal polarity mode. Application of this method for the separation of complicated heparin oligosaccharide mixtures required the addition of volatile electrolyte additives. Triethylamine (10 mM) ammonium bicarbonate (30 mM) showed the best combination of the additives used for the separation of these oligosaccharide mixtures. |
