Anticoagulant activity of a sulfated chitosan

摘要

Chitin prepared from the shells of rice-field crabs (Somanniahelphusa dugasti) was converted into chitosan with a degree of acetylation of 0.21 and then sulfated with chloerosulfonic acid in N,N-dimethylformamide under semi-heterogeneous conditions to give 87% of water-soluble sulfated chitosan with degree of substitution (d.s.) of 2.13. ~1H NMR revealed the sulfate substitution at C-2, C-3 and C-6. Gel fitration on Sepharose CL-6B of the sulfated chitosan gave three fractions with average molecular weights of 7.1, 3.5, and 1.9 X 10~. The three sulfated chitsoan preparations showed strong anticoagulant activities, with the same mechanism of action observed for standard therapeutic heparin.