An in situ gel-forming system composed of rutin- and tyramine-conjugated chitosan derivatives, horseradish peroxidase (HRP), and hydrogen peroxide (H(2)O(2)) was prepared and applied to dermal wound repair. Rutin was employed to enhance production and accumulation of extracellular matrix in the healing process. In vitro study demonstrates that released rutin significantly enhanced cell proliferation as compared with media without rutin. In vivo wound healing study was performed by injecting hydrogels on rat dorsal wounds with a diameter of 8 mm for 14 days. Histological results demonstrated that rutin-conjugated hydrogel exhibited enhancement of wound healing as compared with treatments with PBS, hydrogel without rutin, and a commercialized wound dressing (Duoderm). More specifically, rutin-conjugated hydrogels induced better defined formation of neo-epithelium and thicker granulation, which is closer to the original epithelial tissue. As a result, this study suggests that the in situ gel-forming system can be a promising injectable gel-type wound dressing.

Fast in situ forming supramolecular hydrogels consisted of the tyramine-conjugated supramolecular structures and chitosan derivative were prepared via an enzymatic reaction with horseradish peroxidase (HRP) and hydrogen peroxide (H(2)O(2)). The gel formation was varied within a time period of 5 s to 10 min by controlling the concentrations of HRP, H(2)O(2), and polymers. Tyramine conjugation at different sites of the supramolecular structure resulted in significant changes in physical properties and the degradation time of the hydrogels that were confirmed by water uptake, compressive strength and degradation tests. In addition, the hydrogels showed a good cytocompatibility in vitro. These hydrogels could be promising injectable biomaterials with adjustable degradation times to control both the cellular behaviors as a regenerative cell matrix and the drug release behavior as a drug delivery vehicle.

No abstract

No abstract