Preparation,Antibacterial And Promoting Repair Effect Of SA/PVA-Based Aerogel Dressings

Based on the advantages of non-toxic,biodegradable and good biocompatibility of polyvinyl alcohol(PVA)and sodium alginate(SA),this paper used SA and PVA as raw materials,and prepared SA/PVA composite aerogels by a freeze-thawing cyclic process and freeze-dried molding.The effects of the number of freeze-thawing cyclic on its swelling and degradation properties were explored.The physical and chemical structure,physical and chemical properties,and biocompatibility of the composite aerogels were tested.The results showed that the composite aerogels prepared by three cyclic freeze-thawing had relatively good swelling and degradation properties.The composite aerogels had a three-dimensional network structure,which was beneficial to the growth and proliferation of fibroblasts.With the SA content increased,the water absorption,water retention and porosity of the composite aerogels were improved.The water absorption of PS4 aerogel could reach 1376%,and the porosity could reach 95.1%.The tensile strength of SA/PVA composite aerogels decreased from 1.84 MPa to 0.74 MPa.In addition,the slow degradation rate of the SA/PVA composite aerogels could ensure its stability during use.The SA/PVA composite aerogels was non-hemolytic materials with good biocompatibility,and had potential application value in wound healing.In order to improve the mechanical properties of SA/PVA composite aerogels,the SA/NCC/PVA composite aerogels was prepared by using SA and PVA as base materials and adding a certain content of NCC.The test results showed that with the NCC content increased,the water absorption of the composite aerogels increased and the porosity decreased.Compared with the control group,the composite aerogels could reduce the water vapor loss by 33.5%?38.8%.The addition of an appropriate amount of NCC significantly improved the mechanical strength of the composite aerogels.Compared with the SA/PVA composite aerogels,the tensile strength of the composite aerogels increased from 0.93 MPa to 1.79 MPa after adding 5 wt%of NCC.The sustained release properties of the AMX-containing composite aerogels made it had good antibacterial properties against E.coli and S.aureus,and could control wound infection and could be used as wound dressing.To improve the mechanical properties and biocompatibility of the composite aerogels simultaneously,the SA/GO/PVA composite aerogels were prepared by using SA and PVA as base materials and adding a certain content of graphene oxide(GO).The physical and chemical structure,physical and chemical properties,and biocompatibility and other in vitro tests and in vivo wound healing evaluation were tested.The results showed that the composite aerogels had a three-dimensional network structure,and as the GO content increased,the pore size of the composite aerogels gradually decreased.When the GO content was 0.5 wt%,the water absorption of the composite aerogels could reach 1361%.Compared with the control group,the addition of GO could reduce the water vapor loss rate of the composite aerogels and avoid excessive water dispersion,thereby providing a moist healing environment for the wounds.When the GO content increased from 0 wt%to 2 wt%,the tensile strength of the composite aerogels increased from 1.03 MPa to 1.91 MPa,and the prepared composite aerogels had good strength and toughness.The prepared composite aerogels were non-hemolytic material,and the addition of an appropriate amount of GO had a positive effect on cell activity,and the composite aerogels of 1 wt%GO content had the best effect in promoting cell proliferation.With the content of GO increased,the encapsulation efficiency and drug loading of the composite aerogels on norfloxacin(NFX)increased,and the drug-loaded composite aerogels had good antibacterial effect on E.coli and S.aureus.In vivo wound healing evaluation showed that NFX-loaded composite aerogels could accelerate the wound healing process effectively,and had the potential as a wound dressing.