Stimulation of wound healing by PU/hydrogel composites containing fibroblast growth factor-2

In this study, polyurethane (PU)/hydrogel composites were fabricated for wound healing applications. The hydrogel is a copolymer of thermosensitive N-isopropyl acrylamide (NIPAAm) and acrylic acid (AAc). γ-ray irradiation was employed to simultaneously copolymerize NIPAAm with AAc and graft the hydrogel onto porous PU. Fibroblast growth factor-2 (FGF-2) was incorporated into the composite to facilitate wound healing. The physical properties of the composites were characterized, the in vitro release of FGF-2 was examined, and in vivo tests were conducted. The results indicate that the thermosensitive hydrogel can absorb most of the wound exudates due to its high water uptake ability. Due to its thermosensitive properties, the PU/hydrogel composite is easier to strip off than that of commercial wound dressing, which prevents additional injury to the wound when replacing the wound dressing. In vivo results show that the PU/hydrogel composite incorporating FGF-2 could accelerate wound healing and reduce scar formation.