6-oxychitins, novel hyaluronan-like regiospecifically carboxylated chitins

Crustacean chitins and fungal chitin-glucan complexes are subjected to regi ospecific oxidation at C-6 with NaOCl in the presence of Tempo(R) and NaBr at 25 degrees C in aqueous solution. The resulting products have anionic ch aracter and are fully soluble over the entire pH range; they lend themselve s to metal chelation, polyelectrolyte complex formation with a number of bi opolymers including chitosan, and to microsphere and bead formation. 6-Oxyc hitin coagulates papain, lysozyme and other hydrolases active on chitosans. 6-Oxychitins of fungal and animal origins, in the form of free acids, salt s and esters, might find use as surrogates of hyaluronans and of bacterial antigens in medical and health care products. (C) 1999 Elsevier Science Ltd . All rights reserved.