The Biocompatibility Of Graphene Oxide/chitosan 3D Composite Scaffold

Chitosan(CS)is the cationic polysaccharide in nature widely.It has some properties such as excellent biocompatibility,film-forming property,antimicrobial property and biodegradibility.With this unique advantages,chitosan has wide applicates in skin tissue engineering,bone tissue engineering,periodontal tissue engineering,neural tissue engineering,cartilage tissue engineering,myocardial tissue engineering,cornea tissue engineeringas the scaffold materials currently.However,chitosan has some disadvantages,such as insufficient mechanical strength and degradation rate can not match the rate of formation rate of tissue.Graphene oxide(GO)is a derivatives of graphene,the two-dimensional honeycomb lattice structure is arranged by carbon atoms sp2 conjugation,which is similar as graphene.Graphene oxide has a large number of oxygenic groups,larger surface area and abundant functional groups on the two-dimensional space extension surface with the consistance of a layer of carbon atoms.It is a new carbon material with excellent hydrophilicity to offer plenty of active sites for functional GO and is widely used in drug,gene delivery,biological imaging and tissue engineering.In this study,the pure chitosan scaffold was coated by graphene oxide using thermal and low temperature reduction method to research the biocompatibility of composite scaffold material.L929 cells and neuron cells were cultured at CS,0.02-GO/CS and 1.0-GO/CS composite scaffold materials to investigate the biocompatibility of GO/CS composite scaffold materials in this study.Cell viability was measured using CCK-8 after 48 h at450 nm wavelength.The cell morphology,adhesion and proliferation were observed by immunofluorescence staining under confocal laser scanning microscope.The adhesion position was detected by paraffin section.Then CS,0.02-GO/CS and1.0-GO/CS composite scaffold materials were transplanted into the subcutaneoustissue on the back of rat to investigate the biocompatibility in vivo.Finally,the feasibility of tissue engineering skin scaffolds was studied with the composite materials implanted into the wound skin.Results indicates that cells growth,adhesion and proliferation were along the direction of the surface of the entire scaffolds.The cell viability was the highest and best on 0.02-GO/CS composite material with cell spindle-like shape and spread out on the surface of the scaffold.Compared to the CS and 0.02-GO/CS composite materials,1.0-GO/CS inhibited the cell activity.After materials transplanted,the lymphocytes were rarely seen around the residual scaffolds.On the scaffolds transplanted for 30 days we can only see a small amount of fragments from 1.0-GO/CS sample,while CS and 0.02-GO/CS can be hardly seen.Wound transplantation results showed that all the GO/CS composite scaffold materials could combine with skin tissue and there was no obvious inflammatory reaction.Healing wound rate surrounding CS and 0.02-GO/CS was similar,while1.0-GO/CS was no change.All the results showed that the 0.02-GO/CS composite scaffolds had good biocompatibility and degradability,and could be the agency of tissue engineering skin scaffolds.