Study Of Antibacterial Hydrogel Dressing Applied To Repair Burn Wounds

Skin wounds are a very common physiological phenomenon,and wound repair is a natural healing process,but this process is usually slow and prone to infection,and dressings are often used to help wound healing.Traditional medical dressings such as gauze do not keep the wound moist and the wound heals slowly.Hydrogel dressing is a new type of medical dressing,which is soft and elastic,can relieve pain,is transparent and breathable,easy to view the wound,and can maintain the moist environment required for wound healing.The antibacterial hydrogel dressing not only provides favorable wound healing environment,but also prevents microbial infections.In this research,two kinds of hydrogel dressings with antibacterial activities were designed and prepared and conducted systematic characterization.?I.Study of dextran-hyaluronic acid hydrogel scaffold loaded with Ag NPs In this study,a kind of dextran-hyaluronic acid(Dex/HA)hydrogel dressing with antibacterial function,which has antimicrobial properties by loading nanosilver,was been prepared and characterized.The hydrogel is composed of a three-dimensional network polymer with excellent hydrophilic properties,which can absorb the wound exudate while maintaining the moist environment of the wound and is beneficial to the healing of the wound.Ag NPs is chemically cross-linked by silver nitrate and Dex/HA,and silver ions in silver nitrate are reduced to elemental silver and loaded onto Dex/HA.The results of in vitro experiments show that the Dex/HA composite hydrogel has high porosity,good swelling ratio,uniform distribution of Ag NPs,and can be degraded,which can promote the proliferation of fibroblasts.In vitro antibacterial tests showed that this composite hydrogel has antibacterial function against S.aureus,P.aeruginosa and E.coli.Cytotoxicity results indicate that the antibacterial hydrogel scaffold has good biocompatibility.In vivo evaluation by establishing a rat full-thickness burn infection model,the animal study showed that it can promote epithelial regeneration and collagen fiber formation in homogeneous.The immunohistochemical results showed that it has good anti-inflammatory properties.This study indicates that the hydrogel has an inhibitory effect on S.aureus,P.aeruginosa and E.coli,and has a healing effect on burn wounds.?.Study of dextran-hyaluronic acid-chitosan quaternary ammonium salt hydrogel scaffoldOn the basis of the previous study,the quaternary ammonium chitosan(HACC)and Dex/HA scaffold were blended to prepare Dex/HA/HACC composite hydrogel.HACC itself has antibacterial properties,it is a kind of natural antibacterial materials,and so Dex/HA/HACC composite hydrogel also has antibacterial properties.The results of in vitro experiments show that the Dex/HA/HACC composite hydrogel has high porosity,good swelling ratio,and can be degraded,which can promote the proliferation of fibroblasts.In vitro antibacterial tests showed that the Dex/HA/HACC composite hydrogel has antibacterial function against S.aureus,P.aeruginosa and E.coli.Cytotoxicity results indicate that the antibacterial hydrogel scaffold has good biocompatibility.In vivo evaluation by establishing a rat full-thickness burn infection model,and the animal study showed that the composite hydrogel can promote epithelial regeneration and collagen formation.This study indicates that Dex/HA/HACC hydrogel has an inhibitory effect on S.aureus,P.aeruginosa and E.coli,and has a healing effect on burn wounds,however,the antibacterial effect is not as good as the previous hydrogel scaffold.