Preparation Of Skin Tissue Engineering Scaffolds By Electrospinning And Research On Biocompatibility

Skin wounds and extensive injuries take great pains to patients,so skin grafting have been a problem to researchers.With the development of tissue engineering,fabricating artificial scaffolds to solve skin grafting have potential applications.Electrospinning is widely used in tissue engineering,because it can produce fibers mimicking extracellular matrix which is conducive to cell growth and adhesion.In this paper,two tissue engineering skin scaffolds were prepared by electrospinning.The microstructures and other physical properties of the two scaffolds were further studied,and the cytotoxicity,cell proliferation and biocompatibility of the two skin scaffolds were investigated by in vitro or in vivo implantation experiments.The details are briefly summarized as follows;(1)The gelatin nano-fibers were prepared by electrospinning,and the gelatin skin scaffolds were obtained by chlorine dioxide steam treatment.The microstructure of the gelatin skin scaffolds were characterized by scanning electron microscope(SEM).The results show that homogeneous nano-fibers with a diameter of about 150nm.Moreover,water solubility test and mechanical properties test showed that the gelatin nano-fibers treated with chlorine dioxide could meet the requirements of skin scaffolds.The degradation rate of gelatin nano-fibers before and after treatment with chlorine dioxide were studied.The results showed that the weight loss rate of skin scaffolds were significantly decreasing after ClO2 treatment.Furthermore,cellular adhesion and proliferation was excellent on cross-linking gelatin nano-fibers.In rats models,frozen sections and H&E staining showed that the method possessed both outstanding biocompatibility and no immunological reactions and neovascularization,which further verified the excellent biocompatibility of scaffolds.(2)Nano-ZnO with antibacterial properties was prepared by liquid deposition method.The nano-ZnO with a diameter of about 20nm was successfully characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM)and particle size analyzer(DSL).Then,several amount of nano-ZnO doped CS/PLGA skin scaffolds were prepared by electrospinning.The microstructures of these skin scaffolds were characterized by scanning electron microscopy(SEM).AS shown,the nano-fibers were successfully prepared with uniform diameters.And the effect of doping amount of nano-ZnO on electrospinning fibers were studied,it was found that there was no fiber when the doping amount of nano-ZnO was 7%.The mechanical properties and in vitro degradation rate of four kinds of skin scaffolds were also discussed.The antibacterial activity test showed that the amount of nano-ZnO was positively correlated with the antibacterial activity.Besides the cell proliferation of the four skin scaffolds was analyzed,the results showed that the composite skin scaffolds doped with 1%nano-ZnO could promote cell proliferation.The growth of human skin fibroblasts in the skin scaffolds were observed by scanning electron microscope(SEM).As a result,the cells could proliferate,adhere and grow outside to inside on the scaffolds.In rats models,there was no rejection in the rat implantation experiment,which indicated that the scaffold had good biological activity.The results and conclusions of this paper show that the two skin scaffolds prepared by electrospinning have excellent biocompatibility and safety,so we provide two kinds of potential scaffolds for clinical applications.