An Injectable Thermosensitive Hydrogel Potentially Used for Wound Dressing with Self-adhesive Properties

Wound healing is a complex process, and different kinds of materials are tried to achieve rapid healing. Among them, hydrogel is one of the best candidates for would dressing due to its distinctive properties, such as high biocompatibility, flexibility, and sensitivity to physiological environments. Injectable hydrogels can be facilely delivered in vivo without massive impairment to the body, as no surgical incision is needed for hydrogel embedment. This is highly consistent with the need of minimal invasion on human body. Multiple stimuli could be applied to achieve its injectability, including pH, temperature, light, ions in body fluids. Thermosensitive hydrogel is commonly used due to its high retention of cells and drugs in the local sites. Poly (N-Isopropylacrylamide) (PNIPAM) could be applied because PNIPAM-based polymers can achieve fast gelling at body temperature. Additionally, the introduction of dopamine could provide self-adhesive property for wound dressing applications because of possible bonds with cells, tissues and inorganics. In this thesis, a series of PNIPAM-based, dopamine-modified hydrogels are prepared. They show rapid gelation, high water content, degradability, no cytotoxicity of degradation product to cells, and high in vivo biocompatibility. These hydrogels could also improve cell adhesion as well as promoting cell growth and proliferation. Moreover, the hydrogels could potentially present anti-bacterial properties when silver could be coated onto the hydrogel, which could provide further advantages in would dressing