Polymer mixtures of anionic and cationic polysaccharides and use thereof

摘要

Described in the present application are compositions comprising mixtures of polyanionic polysaccharides and polycationic polysaccharides consisting of oligosaccharide derivatives of chitosan. In the compositions of the invention said mixtures have proven to be soluble in aqueous environments, despite ionic complexes forming between the acid polysaccharides and chitosan derivatives. Said compositions have also demonstrated significant rheological behavior with an unexpected increase in viscosity and viscoelasticity, although the polysaccharides used have relatively low average molecular weights. The said solubility and rheological behavior renders the compositions of the invention particularly advantageous from the biomedical application viewpoint, in particular for viscosupplementation and particularly in the field of articular pathologies and of ophthalmic surgery.

主权项

1. A polysaccharide composition comprising aqueous solutions of mixtures of at least one anionic polysaccharide and at least one oligosaccharide derivative of chitosan, wherein the at least one anionic polysaccharide has a molecular weight of at least 100 kDa;
the chitosan derivatives have a degree of derivatization of at least 40% and the aqueous solutions have an ionic strength of at least 50 mM and not greater than 175 mM and a pH of at least 7 and wherein the at least one anionic polysaccharide and the at least one oligosaccharide derivative of chitosan remain in solution without phase separation and without formation of coacervates and the polysaccharide composition exhibits a synergistic increase of viscosity and viscoelasticity in comparison to the anionic polysaccharide.