低温兼容的球形旋转器和定位器用于神奇角度旋转动态核极化
Lauren E Price1, Nicholas Alaniva1, Marthe Millen1
1Department of Chemistry and Applied Biochemistry, ETH Zürich, Zurich 8093, Switzerland.
Magnetic resonance (Gottingen, Germany)
|October 31, 2023
概括
这项研究优化了用于动态核极化 (DNP) NMR的冷魔法角度旋转 (MAS). 新的定位器可以在更大的样本体积上进行DNP实验,从而实现显著的信号增强.
科学领域:
- 固态核磁共振 (NMR) 光谱学 固态核磁共振 (NMR) 光谱学
- 动态核极化 (DNP) 增强技术 增强技术
- 对于光谱应用的冷工程.
背景情况:
- 魔法角旋转 (MAS) 对固态NMR至关重要,冷温度提高了灵敏度.
- 动态核极化 (DNP) 显著增强了NMR信号,但通常需要很小的样本体积.
- 在MAS技术的进步,特别是球形旋转器,为更大的样本容量提供了潜力.
研究的目的:
- 用9.5毫米直径的球形旋转器优化和实施冷MAS的定位器.
- 为了使DNP实验能够在比以前可行的更大样本量上进行实验.
- 为了实现高DNP增强,在低温温度下提高线稳定性.
主要方法:
- 设计和制造一种用于冷MAS的新型定位器,可容纳9.5毫米球形旋转器.
- 集成样品插入/弹出机制,以方便用户使用.
- 在7特斯拉和105-107K的旋转稳定性和DNP性能的表征.
主要成果:
- 证明温度独立的旋转稳定性为*Hz*是可以忽略不计的.
- 对于124微升和223微升的样本体积,分别实现了223和200的DNP增强.
- 实验使用4M 13C,15N标记尿素和20mMAMUPol在105-107K和7T的糖醇水矩阵中进行实验.
结论:
- 开发的冷MAS定位器有效支持大样本体积的DNP实验.
- 该系统显示了高DNP增强,使其适合敏感的固态NMR研究.
- 这一进步有助于在固态NMR中研究更大,更稀释或更不敏感的样本.
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