Corrosion and Protection Center, Key Laboratory for Environmental Fracture (MOE), University of Science and Technology Beijing, 100083, China.
Corrosion and Protection Center, Key Laboratory for Environmental Fracture (MOE), University of Science and Technology Beijing, 100083, China.
Colloids Surf B Biointerfaces. 2017 Aug 1;156:62-70. doi: 10.1016/j.colsurfb.2017.05.015. Epub 2017 May 8.
The adsorption of proteins has great influence on the biocompatibility, lubrication and corrosion properties of implantable metals. The subsurface microstructure of metals can be easily changed during the manufacturing or service processes and it is easily ignored. The same chemical composition but with various surface microstructures can result in very different adsorption behaviour. In this study, mechanical polishing, electrochemical polishing and shot peening methods were used to generate different gradient deformed surfaces for CoCrMo alloys. The increase of the residual compressive stress and the decrease of grains to a nano-size on the deformed subsurface can effectively enhance the activity of metal atoms and improve the element diffusion, that is helpful in forming a more compact passive film. This can increase the contents of oxides on the surface, and then enhance the electrostatic force and increase the surface's positive charge density as well as adsorption sites. All of the above facilitated the adsorption of the negatively charged albumin onto the alloy surface.
蛋白质的吸附对可植入金属的生物相容性、润滑性和腐蚀性有很大的影响。金属的亚表面微观结构在制造或使用过程中很容易发生变化，而这一点很容易被忽视。相同化学成分但具有不同表面微观结构的金属会导致非常不同的吸附行为。在本研究中，采用机械抛光、电化学抛光和喷丸处理方法在 CoCrMo 合金上生成不同梯度的变形表面。变形亚表面残余压应力的增加和晶粒细化至纳米尺寸可以有效地提高金属原子的活性，促进元素扩散，有助于形成更致密的钝化膜。这可以增加表面氧化物的含量，从而增强静电力，增加表面的正电荷密度和吸附位。所有这些都促进了带负电荷的白蛋白吸附到合金表面上。
