The Sulfonation of Chitosan

Abstract

Sulfation of chitosan with pyridine-chlorosulfonic acid yielded an amorphous sodium salt which had an anticoagulant activity of 56 I. U./mg. It had a molecular weight (by light scattering) of 456, 000 or a D. P. of 1280. It was approximately twice as toxic as heparin. A homogeneous sulfation method was established, using the sulfur trioxide-N, N-dimethylformamide complex in an excess of N, N-dimethylformamide. Sulfated chitosan thus obtained had an anticoagulant activity of 50 I. U./mg. and a D. P. (by light scattering) of 530. Its acute LD50 (mouse, intravenous) was about equal to that of heparin. © 1959, American Chemical Society. All rights reserved.