Centre National De La Recherche Scientifique

Rhone-poulenc Sante

Societe De Developpement Des Utilisations Du Cuir - Saduc

Christian Gagnieu

Hugues Porte

Odile Damour

Christine Franzoni

Frederique Poinsignon

Jacques Marichy

Christian Echinard

Christian Collombel

Michel DuBois

This biomaterial comprises at least a compound consisting of an association of collagen, chitosan acetylated to a degree of acetylation between about 10 and about 40% and of glycosaminoglycans. It has its application in orthopedics and plastic surgery and for making extracellular matrices for regeneration of nerve cells and bones as well as biocompatible envelopes. A particular application is the making of artificial skin consisting of a dermal layer of the velvet type obtained from biomaterials such as those described above. The process of obtaining this dermal layer consists in adding a collagen solution of the chitosan, then in adding to the collagen-chitosan a mixture of chondroitins 4- and 6-sulfate.

Biomaterials with a base of mixtures of collagen, chitosan and

The present invention relates to a process for purifications of natural or synthetic polymers in solution, water-soluble or soluble in water-alcohol medium and comprising sulfate groups, the process consisting essentially, on the one hand, of a selective precipitation in which the sulfated polymers to be purified are complexed in acid medium with a polyamine insoluble at a pH greater than 7 and, on the other hand, after isolation of the complex thus formed, of a progressive solubilizing of the sulfated polymers.

Process for separation of sulfated glycosaminoglycans

Novel organosoluble derivatives of chitosan, useful in coating biologically active feedstuff additives intended for ruminants, to provide coatings which are stable at a pH greater than 5 and which release the biologically active substance at a pH below 3.5, consist of a random chain of units represented by the formulae: ##STR1## in which: R.sub.1 represents an alkylcarbonyl radical (2 to 4 carbon atoms), R.sub.2 represents an alkyl radical (2 to 21 carbon atoms) or an optionally substituted phenyl radical, and R.sub.3 and R.sub.4 represent a hydrogen atom or alkylcarbonyl radicals (2 to 4 carbon atoms).

Chitosan derivatives useful in compositions for coating feedstuff

Growing community of inventors

Lyon, France

Christian Gagnieu