Jens Schwentner

Separation of peracetylated mono- and disaccharides and quantitative analysis of guaran by high-performance liquid chromatography on silica gel

Abstract High-performance liquid chromatography on silica gel was successfully applied to the separation of 15 monosaccharide peracetates. The solvent system acetone-n-hexane gave the most efficient separations at the optimal flow-rate. Dependences of retention times or capacity factors on flow-rate or pressure were determined for all derivaties. The chromatograms obtained showed clear separations of all derivatives, including epimers and anomers. Similarly, 12 disaccharide peracetates were analysed. The best solvent system was acetone-n-pentane, and again the resulting chromatograms showed excellent separations. For detection both a UV photometer and a refractive index detector can be used, depending on the eluent. Acid cleavage and subsequent peracetylation of the polysaccharide guaran gave a mixture of peracetylated monosaccharides. The interpretation of the chromatogram led to qualitative results and, after careful calibration, to quantitative results for the ratio of galactose to mannose residues in guaran.