Fabrication Of Recombinant Human-source Collagen Nanofibrous Scaffold And Its Biocompatibility Testing

BackgroundAt present,more and more skin tissue engineering materials have been used in the treatment of burn wounds,and the development of dermal substitutes has become the focus of skin tissue engineering research.But the applied limited promotion of artificial leather,often because the scaffold vascularization is slow,poor biocompatibility,poor ability to resist infection and expensive price,at the same time how to simulate natural somatic cell matrix structure is still a hard point in the skin tissue engineering structure design.Therefore,the better scaffold structure design scheme and the selection of suitable biomaterials are two keys to develop new artificial dermal substitutes and simulate extracellular matrix.Bracket of the electrostatic spinning technique was used to prepare nanofibers with high specific surface area,high porosity and interconnected three-dimensional network structure,compared with the traditional technology of the preparation of materials can better simulate the natural extracellular matrix structure.Collagen as the main material of dermal substitute is widely used,and the recombinant human collagen used in this study by gene engineering design of collagen gene sequence and then translation production,compared to the extraction of collagen from the animal,has the advantages of hydrophilicity,no disease problems,and easy industrialization.This topic from the perspective of the scaffold structure choose electrostatic spinning technology design nano fiber scaffold with human recombinant collagen which is a new typed of bionic material,in order to prepare scaffolds for skin tissue engineering attributes better biocompatibility more satisfactory,lay the foundation for future clinical application to guide the development of a new generation of artificial dermal substitute.Part one : Preparation and characterization of recombinanthuman-source collagen nanofibers stents properties testingObjective: The electrospinning technology preparation of recombinant human-source collagen nanofibers stents,and through the characterization testing properties evaluation of the structural function,lay the foundation for the next step research.Methods: Electrospinning technique was used to prepare collagen nanofibers by the restructuring,and animal collagen nanofibers,restructuring lyophilized collagen sponge contrast,respectively for SEM observation of morphological structure and fiber diameter,porosity,mechanical property testing,contact Angle measurement,such as in vitro degradation experiment to evaluate human recombinant collagen nanofibers characterization properties.Results: Recombinant human-source collagen nanofibers diameter was appropriate,crosslinking before(1295±382)nm,while after crosslinking fibre diameter was(1225±0365)nm.High porosity,crosslinking before porosity was(93.32±1.13)%,after crosslinking porosity was(92.56±1.67).Good hydrophilicity,contact Angle was(13.85±3.03)°.Mechanics performance,crosslinking before average breaking elongation(5.19±3.45)%,the average breaking strength was(8.02±1.98)MPa,the average young’s modulus was(187±2.33)MPa.Conclusion: We have a certain understanding of the chemical and physical properties of collagen nanofibers,especially for the diameter,hydrophilicity,mechanics performance,degradation rate.the results for the optimization of recombinant human-source collagen tissue engineering scaffolds has a certain guiding role.Part two : Restructuring collagen nanofibers stents biocompatibility testingObjective: By in vitro biocompatibility test evaluation of the biocompatibility of the recombinant human-source collagen collagen nanofibers,clear it as the potential of tissue engineering scaffolds.Methods: According to national standard GB/T16886 restructuring collagen nanofibers were hemolysis test and cytotoxicity test.Extract the original generation of human fibroblasts and cultivation with nanofiber scaffold,respectively by SEM observation and determined by MTT method to detect cell adhesion and proliferation of c recombinant human-source collagen nanofiber scaffold.Rat subcutaneous experiment preparetions,contrast with degradable suture gut,evaluation of recombinant human-source collagen nanofibers caused by inflammation in the body.Wound implanted experiment through the histological examination to evaluate its effect on wound healing.Results: With cytotoxicity test and the hemolysis test results show that the material of cytotoxicity test and hemolysis test are in accordance with the national standard GB/T16886.SEM observation of the material planting fibroblasts and determined by MTT test results show that the cells on the scaffolds proliferation condition is obvious.Rat subcutaneous preparetions experimental results showed that restructuring is collagen nanofibers cause inflammation in the body is lower than the commercially available biodegradable suture gut,wound implant experiments show that recombinant human-source collagen nanofibers can promote wound healing,also promote vascularization effect.Conclusion: Recombinant human-source collagen nanofibers has good biocompatibility,and can be a potential application in tissue engineering.