Fabrication of a novel blended membrane with chitosan and silk microfibers for wound healing: characterization, in vitro and in vivo studies.

Pure chitosan membranes present insufficient mechanical properties and a high swelling ratio, which limits their application in biomedical field. In this study, silk microfibers were obtained by chemical hydrolysis, and a novel type of chitosan/silk microfiber (CS/mSF) blended membrane was reported and its multiple physical properties were evaluated. The mechanical properties were significantly improved after blending silk microfibers with a chitosan matrix, while the swelling ratio was decreased. Observation of the surface microstructures of the blended membranes via scanning electron microscopy showed abundant embedding of mSF into the CS matrix, as well as connections among mSF. In vitro cytocompatibility was also investigated, and the blended membranes exhibited significant cytocompatibility, which was demonstrated by cell proliferation and cell morphology. Furthermore, the in vivo healing effects of the blended membrane as a wound dressing were determined on a full-thickness skin wound model of rats. Animal studies revealed that the membranes containing mSF exhibited increased wound healing efficiency compared with pure CS membranes and treatment without wound dressing. From an examination of histological changes, a higher level of epithelialization and collagen formation was observed with treatment of CS/mSF blended membranes after a 21 day repair period. In conclusion, our results indicated that the blended membranes with CS and mSF might be a potential candidate material for wound healing.