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Updated: Jun 22, 2025

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Methane Hydrate Crystallization on Sessile Water Droplets
Published on: May 26, 2021
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有效地确定关键的水活动,并对水合物-无水合物稳定性关系进行分类
Xin Yao1, Tianyi Xiang2, Shuang Chen1
1Research & Development, AbbVie Inc., North Chicago, IL 60064, United States.
Journal of pharmaceutical sciences
|June 27, 2024
概括
新的方法简化了对水合物稳定性的关键水活性 (awc) 的确定. 这些方法为制药水晶表征的传统技术提供了更快,更少的资源密集型替代方案.
科学领域:
- 固态化学和制药科学.
- 结晶和多态学研究.
- 药物物质的物理化学表征.
背景情况:
- 在制药配方中,水化合物稳定性至关重要,由关键水活性 (awc) 决定.
- 传统的wc测定方法是繁且耗时的.
- 需要有效和准确的方法来预测水合物-无水合物平衡.
研究的目的:
- 开发简单,互补的解决方案和基于固体的方法来预测一个wc.
- 根据热力学特性对水合物-无水合物关系进行分类.
- 验证使用卡巴马泽和神曲素的新方法.
主要方法:
- 基于溶液的方法:使用内在溶解率 (IDR) 或溶解率预测wc.
- 基于固体的方法:通过差分扫描热量计 (DSC) 来预测脱水温度 (Td) 和度 (ΔHd) 的wc.
- 与传统的酸盐-无酸盐泥和溶解度测量进行比较.
主要成果:
- 新的方法提供一个wc值,与传统的卡巴马泽和神素的技术很好地一致.
- 提出了基于Td和ΔHd的水合物-无水合物关系的四类系统.
- 卡巴马泽平和西奥菲林水合物-无水合物对属于第4类 (ΔHd0,Td<373K),表明只有当T
d时才存在一个wc.
结论:
- 开发的基于溶液和固体的方法对于确定wc.有效和高效.
- 新的分类系统有助于理解和预测水合物-无水合物行为.
- 这些发现有助于优化制药水合物的结晶和配方策略.
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