作为一种方法来表征固态活性药物成分的NMR纵向旋转框架放松时间 (T1ρ) 与弱自旋锁定场:概念证明
Luisa Souza Almeida1, Rodrigo Henrique Dos Santos Garcia2, Julian Ticona3
1São Carlos Institute of Chemistry, University of São Paulo, 13566-590 São Carlos, Brazil.
Analytical chemistry
|May 13, 2024
概括
核磁共振 (NMR) 纵向旋转放松时间 (T1ρ) 有效地区分了药物多形体. 这种方法为T1和T2提供了一个敏感的替代方法,用于固态特性.
科学领域:
- 固态化学 固态化学
- 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:
- 在低场NMR中常规的T1和T2放松时间在区分固体药物多态体方面存在局限性.
- 核磁共振 (NMR) 纵向旋转放松时间 (T1ρ) 对分子动力学敏感,可能提供增强的分化能力.
研究的目的:
- 为了比较T1,T2和T1ρ放松时间在区分非活性 (A) 和活性 (C) 晶体形式的梅本达的有效性.
- 为了评估旋锁磁场强度 (B1) 对T1ρ的微分功率的影响.
主要方法:
- 使用0.47 T的低场NMR光谱.
- 测量T1,T2,和T1ρ放松时间是两个形式的梅本达.
- T1ρ测量使用一系列弱旋锁B1场 (0.080.80 mT) 进行.
主要成果:
- T1和T2的放松时间显示,梅本达的A型和C型之间没有统计学上显著的差异.
- 当用弱旋锁B场测量时,T1ρ放松时间在两种形式之间具有统计学上的差异.
- T1ρ证明了在活性C形式中至少10%的非活性A形式的检测极限.
结论:
- T1ρ,特别是当用弱旋锁B1场测量时,是一种比T1和T2更有效的方法来区分Mebendazole多态.
- 该技术提供了一种简化和互补的方法来表征固体活性药物成分和其他固态材料.
- 对于分子动态的T1ρ的敏感性使其成为固态分析的宝贵工具.
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