Key Laboratory of Marine Environmental Corrosion and Bio-fouling, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
Institute for Translation Medicine, Medical College, Qingdao University, Qingdao 266021, China.
Mater Sci Eng C Mater Biol Appl. 2018 Nov 1;92:11-19. doi: 10.1016/j.msec.2018.06.023. Epub 2018 Jun 12.
316L stainless steel has been widely used for orthopedic devices. Inflammatory response and direct contact with abundant proteins after implantation lead to corrosion issues of biomedical stainless steels. The effect of combination of HO and albumin on the corrosion of 316L stainless steel has been investigated for the first time in simulated body fluids at 37 °C with electrochemical and long term immersion tests. ICP-MS measurement after 16 weeks immersion reveals that the total concentration in the presence of both species was substantially higher than physiological saline alone, and even higher than the sum of HO alone and albumin alone. Electrochemical polarisation curves and electrochemical impendence spectra show that albumin accelerated anodic dissolution and suppressed cathodic reaction, while HO promoted cathodic reaction. Also, HO and/or albumin promoted meta-stable/stable pitting corrosion and decreased charge transfer resistance. Accelerated corrosion of 316L stainless steel in the presence of both species was attributed to the promoted formation of Fe oxides and CrOOH by HO and the largely favoured dissolution of these oxides by the addition of albumin, significantly accelerating Fe and Cr release. The synergistic interaction between both species indicates significant underestimation of corrosion rate evaluated solely in physiological saline. These findings suggest the necessity of using more realistic solutions to evaluate corrosion resistance of biomedical alloys for future in-vitro studies.
316L 不锈钢已被广泛应用于矫形设备。植入后与大量蛋白质的炎症反应和直接接触导致了生物医学不锈钢的腐蚀问题。本研究首次在 37°C 的模拟体液中，通过电化学和长期浸泡实验，研究了 HO 和白蛋白的组合对 316L 不锈钢腐蚀的影响。16 周浸泡后的 ICP-MS 测量显示，两种物质存在时的总浓度明显高于单独生理盐水，甚至高于单独 HO 和白蛋白的总和。电化学极化曲线和电化学阻抗谱表明，白蛋白加速了阳极溶解并抑制了阴极反应，而 HO 促进了阴极反应。此外，HO 和/或白蛋白促进了亚稳态/稳定点蚀腐蚀，并降低了电荷转移电阻。由于 HO 促进了 Fe 氧化物和 CrOOH 的形成，白蛋白促进了这些氧化物的大量溶解，显著加速了 Fe 和 Cr 的释放，因此在两种物质的存在下，316L 不锈钢的腐蚀加速。两种物质之间的协同作用表明，仅在生理盐水中评估腐蚀速率会产生显著低估。这些发现表明，未来的体外研究有必要使用更真实的溶液来评估生物医学合金的耐腐蚀性。
