Gellan gum modified hyaluronic acid hydrogels as viscosupplements with lubrication maintenance and enzymatic resistance.

Osteoarthritis (OA) is a common disease caused by damage to articular cartilage and underlying bone tissues. Early OA can be treated by intra-articular injection of viscosupplements to restore the lost viscoelasticity and lubricity of synovial fluid. Hyaluronic acid (HA), as a most standard synovial fluid supplementation, can be easily degraded in vivo, bringing about lower viscoelasticity and increased injection frequency. In this study, we focus on products with reasonable viscoelasticity and long-lasting action time and develop a kind of polysaccharide-based hydrogel viscosupplement (HEG) based on HA chemically modified gellan gum (GG), which can maintain stable viscoelasticity with hyaluronidase for 1 week owing to the fact that the main component of GG still maintains a stable three-dimensional network structure after enzyme treatment. The as-developed injectable HEG hydrogel possesses good biocompatibility, excellent injectability, suitable viscoelasticity, satisfactory lubricity, and enzymatic resistance, demonstrating great potential to intervene in the development of OA.