The present invention relates to a purified, easily produced poly-.beta.-1.fwdarw.4-N-acetylglucosamine (p-GlcNAc) polysaccharide species. The p-GlcNAc of the invention is a polymer of high molecular weight whose constituent monosaccharide sugars are attached in a .beta.-1.fwdarw.4 conformation, and...http://www.google.ca/patents/US5624679?utm_source=gb-gplus-sharePatent US5624679 - Methods and compositions for poly-.beta.-1-4-N-acetylglucosamine biological barriers
