Biocompatilibity-related surface characteristics of oxidized NiTi.
Biocompatilibity-related surface characteristics of oxidized NiTi.
复制标题
氧化镍钛的生物相容性相关表面特性。
DOI：
10.1002/jbm.a.31190
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
T. Jämsä
中科院分区：
文献类型：
--
作者：
A. Danilov;T. Tuukkanen;J. Tuukkanen;T. Jämsä
在本研究中，我们研究了NiTi氧化对与生物相容性相关的材料表面特性的影响。研究了350、450和600 ℃下未氧化和氧化的医用NiTi合金的电子功函数（EWF）与吸附电子理论预测的粘附力之间的对应关系以及表面机械应力对粘附力的影响。将材料表面朝向α-最小必需培养基（α-MEM）的液滴产生的粘附力用作NiTi吸附性质的特征。研究表明，表面处理引起的EWF和机械应力的变化伴随着附着力的变化。NiTi氧化在所有温度下使用引起的附着力和表面应力值相比，非氧化状态的减少。相反，在相同条件下，EWF值显示增加。表面氧化层厚度和其相组成的变化也随之而来。氧化物微晶尺寸的EWF值的范围内的微晶尺寸典型的NiTi表面氧化物作为一种工具的NiTi吸附性能的精细调节的重要作用被证明。纯钛和NiTi的氧化对比表明，Ni对NiTi表面氧化物的EWF值影响不大。
In the present study, we examined the effect of NiTi oxidation on material surface characteristics related to biocompatibility. Correspondence between electron work function (EWF) and adhesive force predicted by electron theory of adsorption as well as the effect of surface mechanical stress on the adhesive force were studied on the nonoxidized and oxidized at 350, 450, and 600 degrees C NiTi alloy for medical application. The adhesive force generated by the material surface towards the drops of alpha-minimal essential medium (alpha-MEM) was used as a characteristic of NiTi adsorption properties. The study showed that variations in EWF and mechanical stress caused by surface treatment were accompanied by variations in adhesive force. NiTi oxidation at all temperatures used gave rise to decrease in adhesive force and surface stress values in comparison to the nonoxidized state. In contrary, the EWF value revealed increase under the same condition. Variations in surface oxide layer thickness and its phase composition were also followed. The important role of oxide crystallite size in EWF values within the range of crystallite dimensions typical for NiTi surface oxide as an instrument for the fine regulation of NiTi adsorption properties was demonstrated. The comparative oxidation of pure titanium and NiTi showed that the effect of Ni on the EWF value of NiTi surface oxide is negligible.