The Preparation, Optimization And Biocompatibility Evalution Of Biodegradable And Anticoagulant Blend Membrane

Objective:Many kind of vascular diseases do harm to the health of human beings, for example arteriosclerosis and hemangiomas. In the case of drug therapy not having obvious effect, it is a good way to treat of replacing the diseased vessels with autologous blood vessels.However, there is limited suitable autologous blood vessels to use. It is significant to prepare the tissue engineering blood vessels to replace the lesion segment. A necessary part of the tissue engineering blood vessels is material scaffold which must have good degradability, biocompatibility, mechanical properties, and antithrombotic adhesion. Natural degradable biomaterials such as gelatin, chitosan, chondroitin sulfate, and heparin are always used to make material scaffold, because they have nice degradability and biocompatibility. Heparin has good anticoagulant, it can improve the blood compatibility of materials. Therefore, in this study, a kind of biological membrane is prepared using biomaterials. Then optimaizes method of making the membrane so that the membrane has good biodegradable and biocompatibility, and certain antithrombotic effect and mechanical properties.Methods:(1) By the MTT assay, evaluates the effect of CMCTS, HECTS, CS, heparin and gelatin on the morphology and proliferation of human umbilical vein endothelial cells (HUVEC), and then selects materials of preparing the membrane combining with the properties of each material;(2) Crosslinkes the selected materials to prepare membrane. Then gets the the optimum material proportion and crosslinking degree of the membrane by evaluating the properties of each membrane with different material proportion and different crosslinking degree. Evaluation contents includes appearance, bibulous rate, swelling ratio, tensile strength, elongation at break, sustained release of heparin, and the ability of antithrombotic of membrane surface.(3) Biocompatibility of the optimal membrane are determined, which includes the hemolysis rate, the cell toxicity, the acute systemic toxicity, the cytocompatibility, and degradability and tissue compatibility of implanting the membrane into rats’ subcutaneous tissues and leg muscles.Results:(1) CMCTS, HECTS, CS, heparin and gelatin don’t inhibit the proliferation of HUVEC at the concentration range of0mg·L-1～2000mg·L-1, nor do them affect the normal cell morphology of HUVEC.(2) The optimal membrane, the bibulous rate is237.39%, the swelling ratio is446.15%, the tensile strength is0.24MPa and the elongation at break is39.07%. The membrane has smooth surface and good flexibility. Heparin in it could release gradually within24h. Its surface does not adhere thrombus.(3) The hemolysis rate of the membrane is lower than5%and the cell toxicity is0. The membrane has good cytocompatibility and tissue compatibility, and no acute systemic toxicity to mice, and it could be degradated completely in the rats after about15weeks.Conclusion:In this study, a kind of blend membrane is prepared which is biodegradable and anticoagulant. The membrane has simple making method. It has good flexibility as well as biodegradability and biocompatibility, and some mechanical properties, anticoagulant and antithrombotic ability.