Photocrosslinked hyaluronic acid hydrogels: Natural, biodegradable tissue engineering scaffolds

TLDR

Rationally designed tissue engineering scaffolds aim to promote natural wound healing and regeneration, and hyaluronic acid—an easily produced, hydrophilic, nonadhesive, naturally biodegradable polymer—plays a key role in wound‑healing processes such as angiogenesis. The study aimed to synthesize a biomimetic hyaluronic acid hydrogel to promote tissue repair. The authors prepared glycidyl methacrylate‑modified hyaluronic acid conjugates and photopolymerized them to produce crosslinked GMHA hydrogels. The GMHA hydrogels exhibited tunable degradation rates and modest changes in swelling and mesh size; higher methacrylate content increased crosslink density and slowed degradation without affecting endothelial cell cytocompatibility or proliferation, and subcutaneous implantation in rats showed good biocompatibility, minimal inflammation, and comparable vascularization to fibrin controls, indicating suitability for further modification with adhesive peptides for wound‑healing applications. © 2003 Wiley Periodicals, Inc., Biotechnol Bioeng 82: 578–589.

Abstract

Abstract Ideally, rationally designed tissue engineering scaffolds promote natural wound healing and regeneration. Therefore, we sought to synthesize a biomimetic hydrogel specifically designed to promote tissue repair and chose hyaluronic acid (HA; also called hyaluronan) as our initial material. Hyaluronic acid is a naturally occurring polymer associated with various cellular processes involved in wound healing, such as angiogenesis. Hyaluronic acid also presents unique advantages: it is easy to produce and modify, hydrophilic and nonadhesive, and naturally biodegradable. We prepared a range of glycidyl methacrylate‐HA (GMHA) conjugates, which were subsequently photopolymerized to form crosslinked GMHA hydrogels. A range of hydrogel degradation rates was achieved as well as a corresponding, modest range of material properties (e.g., swelling, mesh size). Increased amounts of conjugated methacrylate groups corresponded with increased crosslink densities and decreased degradation rates and yet had an insignificant effect on human aortic endothelial cell cytocompatibility and proliferation. Rat subcutaneous implants of the GMHA hydrogels showed good biocompatibility, little inflammatory response, and similar levels of vascularization at the implant edge compared with those of fibrin positive controls. Therefore, these novel GMHA hydrogels are suitable for modification with adhesive peptide sequences (e.g., RGD) and use in a variety of wound‐healing applications. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 82: 578–589, 2003.