瓦尔萨坦的同形系统:热分析对评估分子间相互作用对结构松的影响的贡献
Bruno Ekawa1,2, Hermínio P Diogo3, Ricardo A E Castro2
1Institute of Chemistry, São Paulo State University (UNESP), Araraquara 14801-970, Brazil.
Molecules (Basel, Switzerland)
|September 9, 2023
概括
研究了瓦尔萨坦与4,4'-双和三甲的同型系统. 瓦尔沙坦-4,4'-双胺系统显示了更高的激活能量和更低的玻璃过渡温度,这表明稳定性得到了增强.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 制药科学 制药科学
背景情况:
- 同形系统对于提高药物溶解性和生物可用性至关重要.
- 了解同形系统的物理性质,例如玻璃过渡温度,对于配方稳定性至关重要.
研究的目的:
- 为了研究瓦尔萨坦与4,4'-双二和三甲二烯二元系统中的同形形成.
- 评估不同类型的结合 (与离子) 对同形性质的影响.
- 为了确定稳定的同形系统在玻璃过渡过程中的有效激活能量.
主要方法:
- 基于瓦尔萨坦的共同形态系统的制备和表征.
- 差分扫描热量计 (DSC) 用于热分析和玻璃过渡温度的确定.
- 用热刺激去极化电流 (TSDC) 分析来评估有效的激活能量和脆弱性.
主要成果:
- 瓦尔萨坦与4,4'-双二 (键) 和三甲 (离子键) 的共同形态系统成功形成.
- 玻璃过渡行为偏离了戈登-泰勒预测,瓦尔萨坦-4,4'-双二显示较低的偏差和瓦尔萨坦-trimethoprim显示较高的偏差.
- 稳定的同形化合物 (2:1 Val-Bipy 和 1:1 Val-Tri) 没有结晶.
- 瓦尔沙坦-4,4'-双 (较低的Tg) 显示出更高的有效激活能量,而瓦尔沙坦-三甲 (较高的Tg) 显示出更低的有效激活能量.
- 对于脆弱性和有效激活能量,DSC和TSDC数据之间观察到良好的相关性.
结论:
- 形形成显著影响瓦尔萨坦的热性能和稳定性.
- 分子间相互作用的类型 (与离子结合) 在同形态行为和稳定性中起着关键作用.
- DSC和TSDC是用于表征同形药物系统的物理性质和稳定性的互补技术.
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