Mazumder M M, De S, Trigwell S, Ali N, Mazumder M K, Mehta J L
Department of Applied Science, University of Arkansas at Little Rock, 2801 South University, Little Rock, AR 72204, USA.
J Biomater Sci Polym Ed. 2003;14(12):1351-62. doi: 10.1163/156856203322599699.
Corrosion of metal stents implanted inside an artery can have two adverse effects: (1) tissue reaction and possible toxic effects from the metal ions leaching out of the stent, and (2) loss of mechanical strength of the stent caused by corrosion. The corrosion resistance of Nitinol (Nickel-Titanium) stents and its modulation with different film thickness of polymer coating was studied against an artificial physiological solution using a Potentiostat/Galvanostat and an electrochemical corrosion cell. The corrosion rate decreased rapidly from 275 microm/year for an uncoated surface down to less than 13 microm/year for a 30 microm thick polyurethane coating. Stainless steel (316L) and Nitinol both contain potentially toxic elements, and both are subject to stress corrosion. Minimization of corrosion can significantly reduce both tissue reaction and structural degradation.
（1）组织反应以及支架中金属离子渗出可能产生的毒性作用；（2）腐蚀导致支架机械强度丧失。使用恒电位仪/恒电流仪和电化学腐蚀池，针对一种人工生理溶液研究了镍钛诺（镍 - 钛）支架的耐腐蚀性及其在不同聚合物涂层厚度下的调节情况。未涂层表面的腐蚀速率从每年275微米迅速降至30微米厚聚氨酯涂层时的每年不到13微米。不锈钢（316L）和镍钛诺都含有潜在有毒元素，并且都易发生应力腐蚀。将腐蚀降至最低可显著减少组织反应和结构退化。
