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The Research of Small-caliber Polytetrafluoroethylene Artificial Vessel with Sulfonated Silk Fibroin Film by Low Temperature Plasma Treatment

Author: LiShaoBin
Tutor: ZuoYuSheng
School: Southern Medical University,
Course: Thoracic and Cardiovascular Surgery
Keywords: Artificial blood vessels PTFE Silk fibroin Low-temperature plasma Blood compatibility
CLC: R318.11
Type: Master's thesis
Year: 2010
Downloads: 60
Quote: 0
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Abstract

1, the background since the reform and opening up, with the rapid economic development of our society, the continuous improvement of people's living standards and the great improvement of medical and health undertakings, the country's aging population is increasing year by year. According to statistics by the National Committee on Ageing, the end of 2008, China more than 60 years the elderly population has reached 158 million, accounting for 12% of the country's total population. In accordance with internationally accepted standards, China has entered the aging countries. With an aging population, the incidence and mortality of cardiovascular and cerebrovascular diseases is also increasing year by year. Vascular obstructive lesions of coronary heart disease and other parts of the threat to public health in China has become an important disease, coronary artery bypass surgery, heart, vein and artery bridging surgery annually increasing worldwide each year, according to statistics about the purposes of 850,000 cases of revascularization surgery, autologous blood vessels due to its good tissue compatibility and blood compatibility has always been considered an ideal natural blood vessels bridge materials, and therefore, most of the surgery as an alternative use of autologous blood vessels. Autologous blood vessels the presence of sources of material is limited, based susceptible to vascular conditions and a lot of discomfort, the vascular material poor performance, after easily cause graft stenosis or occlusion, thereby seriously affecting the efficacy of surgery, in addition, drawn additional a variety of surgical procedures will increase the trauma patients developed artificial blood vessels for vascular bypass or replacement surgery, especially small-diameter artificial blood vessels as an alternative to autologous blood vessel revascularization surgery has a very important significance. Artificial blood vessels in the alternative artery has achieved satisfactory results in small and medium-sized arteries, veins, especially small-caliber (diameter <6 mm) vascular grafts, so far, has not an artificial material able to fully meet the current system of small blood vessels clinical the high demands of the application. The main problems is the small-caliber vascular prosthesis material blood compatibility and anticoagulant properties less than autologous blood vessels will be different degrees of fibrin and platelet deposition, when contact with blood, resulting in stenosis, occlusion of blood vessels. Therefore, if able to select suitable materials and methods developed a small arteriovenous Replacement graft suitable for small-diameter artificial blood vessels, not only to meet the needs of the coronary artery bypass surgery and other vascular bypass surgery, but can also be used to develop new without anticoagulation or low-intensity anticoagulation prosthetic valve and bypass, circulatory support pipeline, no doubt the whole heart, the developments in the field of vascular surgery will have a huge role in promoting. Therefore, the subject has a strong practical significance. 2.1 explore the purpose feasibility of plasma sulfonated silk fibroin membrane PTFE composite small-caliber artificial blood vessels (composite vessels) during the preparation; 2.2 Rating composite vascular blood compatibility. 3 Materials and Methods 3.1 argon plasma pretreatment expanded polytetrafluoroethylene artificial blood vessels, and surface contact angle analyzer detection process before and after the contact angle changes; 3.2 silk fibroin membrane coated with polytetrafluoroethylene small caliber artificial blood vessels ; 3.3 Low Temperature Plasma coated silk fibroin film polytetrafluoroethylene vascular sulfonated by XPS surface element analysis, evaluation of sulfonated effect; 3.4 using scanning electron microscopy a composite vascular and vascular surface morphology; 3.5 In vitro: the composite blood vessels and blood vessels were platelet adhesion experiment, dynamic clotting time, recalcification time evaluation of blood compatibility, hemolysis test and evaluation process red blood cells into the bloodstream. 4 Results 4.1 contact angle detection, artificial blood vessels in the treatment of low temperature plasma technology contact angle from 87.7 before treatment. Dropped to 65.1 °, reducing the surface energy of artificial blood vessels, increasing the stability of the silk fibroin membrane adhesion; 4.2 X-ray photoelectron spectroscopy (XPS) to detect the composite vascular and vascular sulfonic acid group content, suggesting sulfur The acid group content of from 0.12% of the ordinary vascular composite vascular group 2.85%, the XPS spectrum S2p peak fitting curve shows the the composite vascular surface of the S atoms is a sulfonic acid group (-SO3H); 4.3 by platelet adhesion test on the composite vessels and vascular scanning electron microscope, seen from the electron micrograph, the surface of the ordinary vascular platelet adhesion and platelet fully expanded, and was flat against the surface of the material, the surface of the composite vascular group rarely platelet adhesion; 4.4 detection by dynamic coagulation tests, the absorbance of the complex vascular group - time curve is located above the ordinary blood vessels, and the downward trend is more moderate, experienced longer periods of time, compared with the ordinary vascular group, the anti-clotting properties ; the composite vascular group recalcificatic the recalcificatic test time was 602.83 ± 33.75s, ordinary vascular group 480.00 ± 33.27s Tip of homogeneity of variance test of homogeneity of variance (F = 0.213, P = 0.665), two-sample t-test prompt results statistically significant difference (t = -6.349, P = 0.000). 5 Conclusion 5.1 using an argon gas of low temperature plasma method can effectively reduce the surface energy of the ePTFE vascular prosthesis, to increase the stability of the coated silk fibroin film; sulfonated using low-temperature plasma technology can be introduced in the inner surface of the ePTFE sulfo acid groups, the preparation process is feasible; 5.2 sulfonated use of low-temperature plasma technology coated with silk fibroin membrane ePTFE artificial blood vessels, which can effectively improve the blood compatibility of the composite vascular improve its anticoagulant blood characteristics.

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CLC: > Medicine, health > Basic Medical > Medical science in general > Biomedical Engineering > Artificial organs and organ > Department of Cardiovascular
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