Investigation Of Graphene And Its Derivatives On The Schwann Cells Behaviors

Peripheral nerve injury(PNI)is a common clinical disease,current clinical techniques for PNI repair still limited,there is an urgent need for the corresponding PNI repair method.Neural tissue engineering technology based on biomaterials,seed cells and in vitro stimulation exhibits prospect in the field.Schwann cell is an important kind of glial cells found in peripheral nervous system.After PNI,a series of functions of promoting nerve regeneration are performed by Schwann cells.Based on the electrical nature and orientation topology of neural system,therefore,it's of great significance to study the effects of electrical stimulation(ES)and scaffold morphology on Schwann cells behavior.Based on the unique physical properties of graphene and its derivatives,the composites containing graphene(and its derivatives)were prepared.RSC-96 cells were used to study the effects of ES,physical and chemical properties of scaffolds on the behavior of RSC-96 cells.So as to provide theoretical scheme and support for PNI repair.The main results list as follows:1.Thermoplastic polyurethanes membranes doped with different concent of graphene were prepared by solution casting method.With the increased of graphene content,the conductivity and mechanical properties of the membranes increased first and then decreased.When the concent of graphene reached 4 wt%,the conductivity of the membranes reached 33.45±5.357 s/m.In vitro biological evaluation,the blood compatibility was lower than 5% of membranes.And 10 m V direct current stimulation could effectively promote the proliferation and growth of RSC-96 cells,and the overload of ES condition may inhibit the growth and spread of Schwann cells.2.Graphene oxide(GO)was prepared by Hummer method,and the fibrous membrane was coated by vacuum assisted filtration technology.The effect of GO coating on the morphology and properties of the scaffolds were studied.The hydrophilicity and mechanical properties of the membranes were significantly improved.When the concent of GO was 0.35 wt%,the orientation characteristics of the fibrous membrane surface remained intact.In vitro evoluation showed that the highly oriented fibrous characteristics led RSC-96 cells to extend and spread,and the presence of GO had no significant effect on the growth and proliferation of RSC-96 cells.3.The product of reduced graphene oxide(r GO)was obtained from reduction of GO by ascorbic acid.The fibrous membranes were prepared by electrospinning,and the electro-activity of fibrous membranes were achieved by r GO coating.The synergistic effect of ES and aligned orientation on RSC-96 cells behaviors was studied.The hydrophilicity,conductivity and mechanical properties of the membranes were enhanced with the coating of r GO.When the concentration of r GO was 0.1wt%,the membrane achieved certain electro-activity and the orientation characteristics were preserved completely.In vitro evaluation,under the ES of 10 m V,the synergism of fibrous orientation and ES enhanced the migration,proliferation and nerve growth factor expression of RSC-96 cells,and the cells spread well and orderly.The novelties of this study are as follows:(1)Neural engineering scaffolds with superior conductivity were prepared based on graphene,and the effect of ES on the behavior of Schwann cells was discussed;(2)By using the simple physical processing technology,the surface functionalization of the fibrous membranes was realized and the orientation characteristics of the fibrous membrane were effectively preserved;(3)The synergistic effects of ES and scaffolds morphology promoted the migration,proliferation and nerve growth factor secretion of Schwann cells.The above research provides strong support for the research and development of PNI repair technology.