Preparation And Performance Study Of Graphene Oxide/Chitosan Film Skeleton-hyaluronic Acid Wound Dressing

Wound dressings play an important role in the wound healing process.With the development of biomedicine,the variety of wound dressings has also become diverse as well as functionalization.Such as film dressings have the advantages of light,thin,and convenient,hydrogel dressings have the advantages of high water absorption and moisture retention.In this paper,a composite film skeleton hydrogel wound dressing was designed and prepared by combining the film with the hydrogel.And then its water absorption,drug sustained release,hemocompatibility,cytotoxicity were tested and analyzed.And finally animal experiments were conducted to explore its effect on wound healing.In this paper,we first prepared graphene oxide by modified Hummers method.And then composite porous films were prepared by dispersing graphene oxide in chitosan solution using polyethylene glycol-20000 as porogen through casting film formation method.And the effects of porogen addition with graphene oxide on porogen residue,water permeability,porosity,mechanical properties,pore structure of porous films were investigated.The results were significant that the porogen residue and porosity of the indicated porous films increased with the increase of porogen.The addition of graphene oxide would then help porogen dissolution,increase porosity and increase water permeability.The effect on the mechanical properties of the porous films then showed a first increasing and then decreasing trend with the increase of graphene oxide content.In the second step of this work,the porous film was used as the skeleton and chitosan-hyaluronic acid hydrogel was fabricated by using EDC/NHS and genipin as the crosslinking agent,respectively.And the molecular groups and crystal structure of the composite film skeleton hydrogel were analyzed by using infrared absorption spectroscopy and X-ray diffraction.The swelling property and infrared photothermal effect of the composite film skeleton hydrogel were also analyzed.The results showed that the film skeleton could be well composited with the hydrogel.The composite film skeleton hydrogel prepared by different crosslinker systems did not have much difference in crystal structure due to the role of film skeleton.Graphene oxide within the film skeleton was better dispersed due to molecular segments rearranged when composite.The water absorption swelling property after the composite greatly improved compared with the film skeleton.And the composite film skeleton hydrogel had a certain photothermal effect under the infrared light irradiation at the band of 808 nm^-1.Finally,the drug sustained-release,hemocompatibility,cytotoxicity of the composite film skeleton hydrogel were tested.The results showed that the effective drug release time of the composite film skeleton hydrogel could reach 11h.The hemolysis rates were all under 5%,and the cell relative value-added rate was more than 75%,implying that it did not possess hemolysis versus potential cytotoxicity.The hydrogel with the best ratio of hemolysis and cytotoxicity was selected for animal experiments.And then,the film skeleton with the same content of graphene oxide and the composite film skeleton hydrogel without graphene oxide were selected as the sample control group to explore the water absorption and moisture retention of the dressing at the wound.As well as to pathologically analyze its wound healing.The results showed better effective moisture retention for the composite film framework hydrogel containing graphene oxide.And it can effectively promote the production of collagen,blood vessels and epidermis at the wound site,and promote wound healing.In this study,a composite film skeleton hydrogel was successfully prepared.Which possessed good drug sustained release properties,did not possess hemolysis and potential cytotoxicity,and met the requirements for use as a biomedical material.And animal experiments showed that it had good moisture retention,could maintain the healing of wounds in a good moist environment,and had a promoting effect on the healing of wounds.The composite film skeleton hydrogel simultaneously has the advantages of film and hydrogel wound dressing.Which provided a new method for protecting wound healing.