Enhanced Biocompatibility of NiTi (NITINOL) via Surface Treatment and Alloying

通过表面处理和合金化增强镍钛 (NITINOL) 的生物相容性

基本信息

批准号：
8102098
负责人：
Norman Donald Munroe
金额：
$ 10.77万
依托单位：
FLORIDA INTERNATIONAL UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-08-29 至 2012-06-30
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): It is projected that by 2015 there will be 133 million Americans over 45, the age at which the increased incidence of heart diseases is documented. Many will require stents (small metal-mesh sleeves implanted in unclogged arteries by angioplasty). This multi-billion dollar industry, with over 2 million patients worldwide, 15% of whom use Nitinol (a NiTi Alloy) stents, has experienced a decline in sales recently, due in part to Thrombosis in about two out of 1000 per year in stable patients with relatively simple artery blockage. Thrombosis is a sudden blood clot that forms inside drug-eluting stents. As a result, the Food and Drug Adminstration, the American Heart Association, and others are calling for a new generation of stents, new designs and different alloys that are more flexible and more adaptable to the arteries. The future of Nitinol as a biomaterial therefore depends on a better understanding of mechanisms by which Nitinol surface can be rendered stable and inert, yet retain flexibility and machinability. Additionally, Ni enrichment and its leaching from the Nitinol surface must be controlled due to its carcinogenicity and deleterious effects in the liver and kidney. Ni also causes necrosis. Therefore, I propose to conduct standard American Society of Testing and Materials (ASTM) potentiodynamic and potentiostatic corrosion tests on the ternary alloys of Nitinol (Ni51Ti49)1-xTax system in the range of 0-20 atomic % Ta to evaluate the corrosion resistance in biological media. Ta, added as a ternary element in the NiTi-alloys, has been proven to impart X-ray visibility, stability, corrosion resistance and other beneficial effects. Inductively Coupled Plasma Analysis will be used to monitor Ni release in biological media. Biocompatibility will be assessed by observing the growth of cells on the material's surface and exploring blood compatibility [platelet spreading, protein adsorption, cell proliferation, inflammatory mediators, etc.] The Nitinol surfaces will be characterized using XRD, DSC, EPMA, Raman Spectroscopy, SEM, etc. I am of the opinion that this applied research effort could improve upon the in-vivo safety and performance profile of NiTi as used in coronary and peripheral arteries, as well as in bodily passageways where the alloy is subjected to corrosivity extremes, ultimately resulting in the even more widespread efficacious medical use of advanced Nitinol alloys

描述（由申请人提供）：预计到 2015 年，45 岁以上的美国人将达到 1.33 亿，据记录，45 岁以上的心脏病发病率有所增加。许多需要支架（通过血管成形术将小型金属网套植入畅通的动脉中）。这个价值数十亿美元的行业在全球拥有超过 200 万患者，其中 15% 使用镍钛诺（一种镍钛合金）支架，最近销量下降，部分原因是每年约千分之二的稳定患者发生血栓。动脉阻塞相对简单的患者。血栓形成是药物洗脱支架内突然形成的血凝块。因此，美国食品和药物管理局、美国心脏协会和其他机构呼吁开发更灵活、更适合动脉的新一代支架、新设计和不同合金。因此，镍钛诺作为生物材料的未来取决于对使镍钛诺表面变得稳定和惰性，同时保持灵活性和可加工性的机制的更好理解。此外，由于镍钛合金具有致癌性并对肝脏和肾脏产生有害影响，必须控制镍的富集及其从镍钛合金表面的浸出。 Ni也会引起坏死。因此，我建议对镍钛诺（Ni51Ti49）1-xTax体系的三元合金在0-20原子％Ta范围内进行标准的美国测试与材料协会（ASTM）动电位和恒电位腐蚀测试，以评估其耐腐蚀性能。生物介质。 Ta 作为三元元素添加到 NiTi 合金中，已被证明可以赋予 X 射线可见度、稳定性、耐腐蚀性和其他有益效果。电感耦合等离子体分析将用于监测生物介质中镍的释放。将通过观察材料表面细胞的生长并探索血液相容性[血小板扩散、蛋白质吸附、细胞增殖、炎症介质等]来评估生物相容性。镍钛诺表面将使用 XRD、DSC、EPMA、拉曼光谱进行表征， SEM 等。我认为这项应用研究工作可以改善镍钛合金在冠状动脉和外周动脉以及身体通道中的体内安全性和性能特征。该合金会受到极端腐蚀，最终导致先进镍钛诺合金在医疗领域得到更广泛的有效应用