Department of Bioengineering, University of California at Riverside, Riverside, CA, 92521, USA.
Materials Science and Engineering, University of California at Riverside, Riverside, CA, 92521, USA.
Sci Rep. 2017 Oct 30;7(1):14335. doi: 10.1038/s41598-017-14479-6.
Magnesium (Mg) alloys are promising materials for biodegradable implants, but their clinical translation requires improved control over their degradation rates. Proteins may be a major contributing factor to Mg alloy degradation, but are not yet fully understood. This article reports the effects of fetal bovine serum (FBS), a physiologically relevant mixture of proteins, on Mg and Mg alloy degradation. FBS had little impact on mass loss of pure Mg during immersion degradation, regardless of whether or not a native oxide layer was present on the sample surface. FBS reduced the mass loss of Mg-Yttrium (MgY) alloy with an oxidized surface during immersion degradation, but increased the mass loss for the same alloy with a metallic surface (surface oxides were removed). FBS also influenced the mode of degradation by limiting the depth of pit formation during degradation processes on commercially pure Mg with metallic or oxidized surfaces and on MgY alloy with oxidized surfaces. The results demonstrated that serum proteins had significant interactions with Mg-based biodegradable metals, and these interactions may be modified by alloy composition and processing. Therefore, proteins should be taken into account when designing experiments to assess degradation of Mg-based implants.
镁（Mg）合金是一种很有前途的可生物降解植入物材料，但要将其临床应用，就需要更好地控制其降解速率。蛋白质可能是影响镁合金降解的一个主要因素，但目前还没有完全了解。本文报告了胎牛血清（FBS），一种具有生理相关性的蛋白质混合物，对镁和镁合金降解的影响。无论样品表面是否存在天然氧化层，FBS 对纯镁在浸泡降解过程中的质量损失几乎没有影响。FBS 降低了表面氧化的 Mg-钇（MgY）合金在浸泡降解过程中的质量损失，但增加了具有金属表面（去除表面氧化物）的相同合金的质量损失。FBS 还通过限制具有金属或氧化表面的纯镁和具有氧化表面的 MgY 合金在降解过程中凹坑形成的深度，影响了降解模式。结果表明，血清蛋白与基于镁的可生物降解金属有显著的相互作用，而这些相互作用可能会被合金成分和处理方式所改变。因此，在设计评估基于镁的植入物降解的实验时，应该考虑蛋白质的因素。
