Cooling rate effects on the structure of 45S5 bioglass: Insights from experiments and simulations
Cooling rate effects on the structure of 45S5 bioglass: Insights from experiments and simulations
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DOI：
10.1016/j.jnoncrysol.2020.119952
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发表时间：
2020-04-15
影响因子：
3.5
通讯作者：
Krishnan, N. M. Anoop
中科院分区：
文献类型：
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作者：
Bhaskar, Pratik;Kumar, Rajesh;Krishnan, N. M. Anoop
由于其在溶解时与活组织结合的能力，45S5玻璃和相关组合物材料被广泛用于人体硬组织的替换、再生和修复。然而，其原子结构的细节仍然存在争议。这部分是由于玻璃的非平衡性质，因为它们的非晶体结构高度依赖于它们的热历史，即淬火期间使用的冷却速率。在此，结合分子动力学（MD）模拟与冷却速率范围超过几个数量级和实验研究，使用核磁共振（NMR），我们调查的标称45S5玻璃组合物的结构。这些结果表明，外推到实验冷却速率时，MD模拟结果可以提供一个合理的估计的45S5玻璃的结构。最后，根据这些结果，我们建议的倾向，磷酸基团形成孤立的正磷酸盐物种。总的来说，这些结果调和了45S5玻璃结构的模拟和实验结果，特别是磷酸基团的形态，这可能是控制45S5玻璃生物活性的关键。
Due to its ability to bond with living tissues upon dissolution, 45S5 bioglass and related compositions materials are extensively used for the replacement, regeneration, and repair of hard tissues in the human body. However, the details of its atomic structure remain debated. This is partially due to the non-equilibrium nature of glasses, as their non-crystalline structure is highly dependent on their thermal history, namely, the cooling rate used during quenching. Herein, combining molecular dynamics (MD) simulations with cooling rates ranging over several orders of magnitude and experimental studies using nuclear magnetic resonance (NMR), we investigate the structure of the nominal 45S5 bioglass composition. These results suggest that the MD simulation results when extrapolated to experimental cooling rates can provide a reasonable estimate of the structure of 45S5 bioglass. Finally, based on these results, we suggest the propensity of the phosphate group to form isolated orthophosphate species. Overall, these results reconcile the simulation and experimental results on the structure of 45S5 bioglass, and particularly on the speciation of the phosphate group, which may be key in controlling the bioactivity of 45S5 bioglass.