使用X射线原子对分布函数和固态NMR探测无形药物固体的分子包装
Zhenxuan Chen1, Haichen Nie2,3, Chris J Benmore4
1Analytical Research and Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States.
Molecular pharmaceutics
|October 6, 2023
概括
对像波萨可纳这样的无形药物的高分辨率结构分析对于稳定性至关重要. 这项研究将X射线PDF和ssNMR结合起来,揭示了无形波萨可纳及其固体分散中的分子包装和相互作用.
科学领域:
- 制药科学 制药科学
- 材料科学是一种材料科学.
- 分析化学是一种分析化学.
背景情况:
- 了解无形制药结构是预测物理化学稳定的关键.
- 有限的高分辨率分析工具阻碍了对无形药物的详细结构调查.
- 无形固体分散对于改善药物的溶解性和生物可用性至关重要.
研究的目的:
- 为了研究无形波萨可纳及其无形固体分散的分子包装和分子间相互作用.
- 为了证明X射线对分布函数 (PDF) 和固态核磁共振 (ssNMR) 的协同作用,用于高分辨率无形结构分析.
- 为了阐明无形固体分散中的药物聚合物相互作用.
主要方法:
- 使用同步射线X射线对分布函数 (PDF) 来分析原子层结构.
- 固态核磁共振 (ssNMR) 19F-13C距离测量提供了补充结构信息.
- 经验潜能结构精细化 (EPSR) 方法用于建模无形结构.
- 应用了主要组件分析 (PCA) 来整合PDF和ssNMR数据.
主要成果:
- 在无形的波萨可纳中发现了刚性构造和短距离的分子间C-F接触.
- ssNMR 19F-13C的距离测量证实了X射线PDF分析的发现.
- PCA揭示了无形固体分散中的药物聚合物相互作用的化学性质的见解.
- 该研究成功地获得了对无形系统的高分辨率结构洞察力.
结论:
- 综合使用X射线PDF和ssNMR,以及先进的建模,为无形药物的高分辨率结构特征提供了强大的方法.
- 了解分子包装和分子间相互作用对于控制无形药物及其分散的物理化学稳定性至关重要.
- 这种方法提供了一条更好地理解和优化无形固体分散配方的途径.
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