Separation and quantitative analysis of the composition of low molecular weight sulfated polysaccharides by size exclusion chromatography

Abstract

As the composition of low molecular weight sulfated polysaccharides is very complex, the quantitative analysis of their compositions is very important for understanding their bioactivity and the purpose of the quality control. A method was developed for the separation and quantitative analysis of the composition of low molecular weight sulfated polysaccharides. The effects of the parameters, such as the mobile phase constitution including ionic strength and pH, column length and temperature, flow rate of the mobile phase on the separation were systematically investigated. The obtained optimal conditions were as follows: two TSK-GEL G2000 SWxl columns (300 mm x 7.8 mm) coupled together; mobile phase, 100 mmol/L Na2HPO4-NaH2PO4(pH 7.0); flow rate, 0.5 mL/min; column temperature, 35 degrees C; injection volume, 5 microL; sample concentration, 10 g/L. The method was validated in terms of its reproducibility and robustness. Under the optimized chromatographic separation conditions, each composition of the low molecular weight sulfated polysaccharide can be clearly separated, and their distribution ratios were quantitatively analyzed. The composition profilings of the samples from United States pharmacopoeia (USP), the two commercial available samples and two home-made samples were quantitatively compared. The method can be used for the quality control of the drugs based on low molecular weight sulfated polysaccharides.