Surface Modification And Properties Study Of Silk Fibroin Fiber Fabric For Vascular Graft

Silk fibroin fiber is a natural polymer with excellent mechanical properties and biodegradability,which has been widely used in the field of biomedical materials.Studies have shown that fibroin fibers woven tubular fabric can be used as a kind of excellent mechanical properties of small diameter artificial blood vessel material,however its biocompatibility is not ideal.In this research,silk fibroin fiber fabric was treated with plasma process technology to increase the number of polar groups on the surface of materials.And then,the regenerated silk fibroin was grafted onto the material surface using the chemical coupling agent EDC/NHS.The purpose is to improve the biological property of SFF,and provide the reference for the development of silk fibroin fiber artificial blood vessels.There were three parts in this paper: firstly,I used the low temperature and low pressure plasma technology to treat the surface of fibroin artificial blood vessel material,and investigated the effects of gas,time,power and vacuum on the treatment efficiency;secondly,I grafted high and low molecular weight regenerated silk fibroin onto the surface of SFF and investigated the effect of protein molecular weight and concentration on grafting efficiency;finally,I evaluated the biocompatibility of the grafted materials by protein adsorption,hemolysis and cytotoxicity tests.The results of the study and the main conclusions were as follows:?1?Compared to O₂ and Ar,the effect of He plasma treatment on the surface morphology,structure and mechanical properties of SFF was the least.The optimization process of He plasma treatment was: the time of 180 s,power of 70 w,vacuum degree of 50 Pa.?2?After the grafting of high molecular weight regenerated silk fibroin,the tensile properties of SFF were improved,but the elasticity and hydrophilicity were decreased.While the grafting of low molecular weight regenerated silk fibroin on to SFF could improve the grafting uniformity and stability,and the degree of elasticity and hydrophilicity of it was lower than that grafting of high molecular weight regenerated silk fibroin.The optimized grafting solution concentration was 1% for high molecular weight regenerated silk fibroin and 5% for low molecular weight regenerated silk fibroin.?3?After the grafting of high molecular weight regenerated silk fibroin,the plasma albumin adsorption of silk fibroin artificial vascular material was increased.The results of hemolysis and cytotoxicity test showed that the grafting of high molecular weight regenerated silk fibroin onto SFF could significantly improve its blood and cell compatibility compared with low molecular weight regenerated silk fibroin.In conclusion,He plasma treatment could obviously improve the hydrophilicity of SFF,while damaged little of the surface morphology and the mechanical properties of SFF.Compared with low molecular weight regenerated silk fibroin,the grafting of high molecular weight regenerated silk fibroin can significantly improve the biocompatibility of SFF,but there were still some problems such as lower elasticity of grafted material should be solved in further research.