[Studies on polysaccharide peptide with high performance gel permeation chromatography]

High performance gel permeation chromatography (HPGPC) has been widely used in the fraction and molecular-weight (MW) estimation of polysaccharides. In this paper, we estimated the MW of major component of polysaccharide-peptide from Corilous versicolor (PSP). These three-components were separated by using two column system (TSK-40 and TSK-50 gel columns) and different NaCl concentration in mobile phase. Calibration curve was prepared from the known MW Dextran T-system. It was found that the MW of PSP was changed in accordance with ion concentration of mobile phase. The MWs of the main component are more than 500000, 120000-19000 and less than 10000 respectively as the NaCl concentrations in mobile phase were less than 0.002, 0.006-0.04 and more than 0.06mol/L. The results showed that the MW of polysaccharide-peptide determined by HPGPC is a relative value that is changed with the concentration of mobile phase. The reason is that the molecular configuration and size of polysaccharide-peptide are changed along with electrolyte concentration in mobile phase. That is, the lower the electrolyte concentration is, the larger the molecular size of polysaccharide-peptide is. We suggest that it is still useful for quality control of PSP as the mobile phase is fixed.