使用拉曼和特拉赫兹振动光谱学研究乙胺-乙基马龙酸共晶体内的多态性
Jiale Zhang1, Yaqi Jing1, Mei Wan1
1Centre for THz Research, China Jiliang University, Hangzhou 310018, China.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
|October 13, 2023
概括
合成了乙胺和乙基马龙酸的两个共晶多态. 特拉赫兹和拉曼光谱学有效地区分了这些多态体,并监测了它们的相变,这对于共晶分析非常有用.
科学领域:
- 固态化学 固态化学
- 材料科学是一种材料科学.
- 晶体学 晶体学是指结晶学.
背景情况:
- 晶合成提供了一条修改药物特性的途径.
- 同晶体中的多态性可能会影响稳定性和生物可用性.
- 区分共晶多态体对于药物开发至关重要.
研究的目的:
- 合成和描述两个新型的乙胺 (ETZ) 和乙基马龙酸 (EMA) 的共晶多态.
- 研究使用特拉赫兹 (THz) 和拉曼光谱来区分这些多态.
- 为了研究这些共晶体由温度和机械应力引起的相变.
主要方法:
- 溶剂蒸发方法用于共晶合成.
- 用于结构分析的X射线晶体学.
- 特拉赫兹 (THz) 和拉曼振动光谱用于表征.
- 差分扫描热度计 (DSC) 和固态研磨用于相位过渡研究.
主要成果:
- 成功合成了ETZ-EMA的两个不同的共晶多态 (I型和II型).
- THz和拉曼光谱均显示了每个多态体的独特光谱指纹,使其能够清晰地区分.
- 在加热 (80-82°C) 或固态研磨时转化为稳定的I型,特别是使用非极性或高极性溶剂.
- 光谱方法准确地检测出共晶形成和相变.
结论:
- THz和拉曼光谱是识别ETZ-EMA共晶多态的高度敏感和准确的工具.
- 这项研究证明了这些光谱技术在监测共晶合成和固态相变的实用性.
- 了解和控制共晶多态性对于制药应用至关重要.
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