Preparation of biocompatible PVA hydrogels as wound dressings by gamma irradiation

Hydrogels have emerged as a new class of materials that are capable of providing appropriate moist environment for wound healing. In this report, gamma irradiation was utilized to prepare flexible, self-adhesive, and biocompatible hydrogel sheets from polyvinyl alcohol (PVA) as wound dressings. The PVA concentrations ranged from 6-10 % (w/v) and gamma doses from 10-80 kGy were first varied to optimize the formation of crosslinked, three-dimensional structure of hydrogels. Based on swelling behavior, the 10% (w/v) PVA solution crosslinked at the dose of 40 kGy was selected to fabricate prototypic hydrogel sheets that could conform over skin contour. The extraction-based MTT assay showed that the hydrogel sheets were cytocompatible with L929 cells. When applied on full-thickness defects in rat model, the hydrogel sheets could facilitate re-epithelization to complete wound closure. These results demonstrate that our PVA hydrogel sheets developed by gamma irradiation can serve as a suitable candidate for wound dressings.