Preparation and characterization of new hydrogels based on hyaluronic acid and α,β-polyaspartylhydrazide

Hyaluronic acid (HA) has been crosslinked with alpha,beta-polyaspartylhydrazide (PAHy). The crosslinking reaction has been performed in acidic medium in the presence of various amounts of N-ethyl-N'-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC). All obtained samples have been characterized by FT-IR analysis and swelling measurements in double distilled water that have confirmed the occurrence of a chemical linkage between two polymers and the affinity towards aqueous medium of HA-PAHy networks, respectively. In vitro degradation assays have been performed in simulated physiological conditions as well as in the presence of hyaluronidase. Experimental data evidenced that HA-PAHy samples undergo a poor chemical and a reduced enzymatic degradation unlike native HA. (C) 2007 Elsevier Ltd. All rights reserved.