Prepared Hydrogel Dressing Based On Hyaluronic Acid For Combining With Cell Sheet And Anti-bacteria

Wounds usually refers to the damage of living skin or tissue.It is generally caused by external injury factors such as surgery,external forces,heat,current,chemicals,low temperature,and internal factors such as local blood supply disorders.In the process of wound repair,a wound dressing that protects the wound bed,promotes skin regeneration,and treats or prevents infections is urgently needed to maintain a suitable microenvironment around the wound interface so that cells can adhere and proliferate correctly to accelerate wound healing.As an ideal dressing,hydrogel has suitable viscosity and mechanical properties,and can absorb the exuded tissue fluid in time and keep the wound moist.Hydrogels based on natural polysaccharides have received extensive research attention due to their advantages of good biocompatibility and non-sensitization.In the first part of this paper,we use hyaluronic acid and soluble glycol chitosan as raw materials for large-scale burn wounds.The cross-linked structure is formed via schiff base reaction between the aldehyde group in the oxidized polysaccharide and the amino group in the glycol chitosan,which is used as a self-healing hydrogel system that can be combined with epidermal cell sheets.The internal morphology of the hydrogel,rheological properties,moisturizing properties,the activity of the cells co-cultured with the epidermal cell sheets,and the changes of the EGF content secreted by the cells were evaluated.Because of its good biocompatibility,it is expected to be used in combination with epidermal cell membrane in wound repair.In the second part of this article,a hyaluronic acid is used as the polysaccharide backbone to graft polyethylene glycol onto its side chain,and a kind of pH sensitive antibacterial hydrogel is constructed by the supramolecular interaction between polyethylene glycol and cyclodextrin,which realizes the controlled release of antibacterial drugs.The rheological properties of hydrogels,sustained release of antibacterial drugs in vitro,blood compatibility,cytotoxicity and antibacterial properties were studied.The results show that the constructed hydrogel has a good pH response behavior in the slightly acid environment generated by bacterial reproduction,and has an excellent bactericidal effect by continuously and effectively releasing antibacterial drugs.