Preparation And Properties Of Composite Scaffolds For Vascular Tissue Engineering

Vascular disease is currently one of the common diseases in clinic, the pathological changes and the damage of blood vessel are caused by atherosclerosis, wound, hemangioma, aging and so on. Once the disease, it can not guarantee the normal supply of blood, need to carry out the replacement of blood vessels. At present, the most common surgical treatment for vascular is replacement, the main material of the replacement has autologous blood vessels, allogenic vein blood vessels and artificial synthetic materials, etc.With the development of tissue engineering, synthetic vessels of artificial materials has become the direction to solve clinical problems for scientists.Ideal scaffold materials should have good biocompatibility, controllable degradation rate, porous three-dimensional structure and good mechanical properties. Studies found that nano wire-prime and sericin protein have good chemical stability, non-toxic side effects on the human body, good biological compatibility and degradation, also have certain growth promoting effect on human cells. Chitosan / glycerol sodium phosphate temperature sensitive system as a kind of biological carrier, has good antibacterial property, promote cell growth, but existing defects in the degradation and mechanical properties。Therefore, this topic will be blending and modified nano wire element, sericin protein, chitosan and sodium glycerophosphate, to prepare porous scaffolds, which combines the advantages of the combination of ingredients, construct a kind of ideal tissue engineering scaffold material.Under the condition of ice bath and stirring, this topic added nano silk fibroin solution, sericin protein solution into chitosan solution sequentially, then slowly dropping glycerophosphate solution to get composite gel, after freezing and drying the composite scaffolds was got.Structural characterization found that the composite scaffold is a porous structure, has penetrating Internal porosity, which has certain plasticity and mechanical strength. To be treated optimally at 121℃ in 25 min with C4G1 Structure ratio,and the pore size was 20-200 nm, which was suitable for the growth of cells. IR spectra show that the internal components of the material are closely combined with the force and hydrogen bond. High pressure treatment makes the initial decomposition temperature of the composite change, so that the initial thermal stability of the material is changed. Biological evaluation: the blood compatibility of the composite scaffold is good, and it accords with the national safety standards. It was degraded gradually with time, which is conducive to cell attachment and growth and proliferation of cells. The composite scaffold material has no obvious cytotoxicity to the cells, and has a certain growth promoting effect on the cell. There is inhibition effect both on Staphylococcus aureus and Escherichia coli.The studies of the effect of composite materials on the growth of vascular endothelial cells found that the vascular endothelial cells cultured with composite materials had good growth, high cell viability and no cell toxicity. Cells have good adhesion to the surface of composite scaffold materials, growing in three-dimensional, which are in favor of the adhesion and growth of vascular endothelial cells and have a certain effect on promoting cell growth.The research shows that the material has excellent properties and has the potential to be used as a material for vascular tissue engineering.