Study Of Antibacterial Skin Scaffolds Applied To Burn Wound Infection

Burn infection is still a challenge for clinic.Autologous transplantation combined with antibiotic is still used as the gold standard for large areas of damaged skin.Therefore,a functional skin tissue scaffold is the most promising method to solve the problem of donor deficiency,immunogenicity and infection.Nature biomaterials have good biocompatible property,degradable,abundant resource,which can be applied as skin substitute.Besides,the infection can be solved by carrying a kind of antibacterial agent.In this research,two kinds of bioactive skin scaffolds with antibacterial properties were designed and prepared for infected-burn wounds.?.Study of gentamicin sulfate-loaded collagen/nano-microcrystalline cellulose skin scaffold[1]In this study,a kind of antibacterial collagen(Coll)/cellulose nanocrystals(CNCs)scaffold was prepared and characterized,which can be applied in skin trauma as a promising dressing.In order to achieve the goal of antibacterial function for a long time,the Gentamycin sulfate(GS)was absorbed in the prepared gelatin microsphere(GMs)then doped in the porous Coll-CNCs freeze-drying scaffold.The CNCs had a width of 20-40 nm and length of 150-350 nm from electron microscopy(TEM),retained the basic chemical structure of cellulose observed from Fourier transform infrared,and increased the machinery properties of Coll scaffold from thermal property analysis.The mean pore size of the composite scaffolds was about 120?m with or without GMs from the SEM.The in vitro release profile of GS showed a sustained release of this GS/GMs/Coll-CNCs composite scaffold.The biological compatibility experiments showed the composite scaffold had low cytotoxicity of NIH-3T3 cells.The inhibition zones indicated the antibacterial efficacy of the composite scaffold against Escherichia coli and Staphylococcus aureus.?.Study of sanguinarine-loaded dextran-hyaluronic acid hydrogel skin scaffoldIn this study,we successfully fabricated dextran-hyaluronic acid(Dex-HA)hydrogel enriched with sanguinarine(SA)incorporate in the gelatin microsphere(GMs),which had high porosity,well swelling ratio,enhanced cell proliferation,and sustained SA release.The in vitro degradation results indicate the SA/GMs/Dex-HA hydrogel can be biodegraded and hydrolyzed.The in vitro antibacterial tests showed that the SA/GMs/Dex-HA hydrogel can inhibit the methicillin-resistant staphylococcus aureus(MRSA)and escherichia coli(E.coli).We evaluated the wound-healing effects and antibacterial properties of SA/GMs/Dex-HA hydrogels in a rat full-thickness burn infection model,the Biatain~?Alginate Ag was set as positive control.The SA/GMs/Dex-HA hydrogel of hematoxylin-eosin(H&E)and Masson's trichrome staining results showed that improved re-epithelialization,enhanced extracellular matrix remodeling,and immunohistochemistry results showed that the expression of TGF-?1 and TNF-?was decreased while the TGF-?3 expression was increased.Our findings suggest that the SA/GMs/Dex-HA hydrogel provides a potential way for infected burn treatment with high-quality and efficient scar inhibition.