Development of photocrosslinkable hyaluronic acid-polyethylene glycol-peptide composite hydrogels for soft tissue engineering.

Hyaluronic acid (HA; also called hyaluronan) is a naturally derived, nonimmunogenic, nonadhesive glycosaminoglycan that has important roles in several wound-healing processes. In previous work, we created photocrosslinkable glycidyl methacrylate-HA (GMHA) hydrogel biomaterials that were cytocompatible, biologically active, and had a decreased rate of hyaluronidase degradation compared with native HA. The goal of the studies presented herein was to explore peptide conjugation techniques to further adjust the material and biological properties of the GMHA hydrogels. We conjugated GMHA with acrylated forms of polyethylene glycol (PEG) and PEG-peptides to yield GMHA-PEG-peptide composite hydrogels. By varying the reactant concentrations, we created stable hydrogels with high peptide conjugation efficiencies (up to 80%), controllable peptide concentrations (in the range of 1-6 micromol peptide per milliliter of hydrogel), and defined physicochemical properties (e.g., swelling ratio, enzymatic degradation rate). These composite hydrogels may prove to be a promising scaffolding biomaterial for a variety of soft tissue engineering applications.