固体相极化矩阵用于从半体结构混合材料中均分布的基因中产生动态核极化
David Gajan1, Martin Schwarzwälder, Matthew P Conley
1Department of Chemistry, ETH Zürich , CH-8093 Zürich, Switzerland.
Journal of the American Chemical Society
|August 28, 2013
概括
具有稳定基的新有机材料作为动态核极化 (DNP) NMR 的高效极化矩阵. 这些材料在没有玻璃形成器的情况下实现高信号增强,简化了固态DNP NMR实验.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 生物物理学的生物物理.
背景情况:
- 固态动态核极化 (DNP) NMR增强了NMR信号的灵敏度.
- 开发有效的极化矩阵对于DNP NMR性能至关重要.
- 现有的方法通常需要玻璃成型添加剂,使样品准备复杂化.
研究的目的:
- 为固态DNP NMR开发新型半孔混合-有机材料作为极化矩阵.
- 调查激素分布和度在DNP增强中的作用.
- 为了证明这些材料与不同激素和分析物的实用性.
主要方法:
- 半孔杂交的二氧化-有机材料与共聚结合的氧化基 (例如TEMPO) 的合成.
- 用特定溶剂 (水,四乙烯) 浸材料.
- 在低温 (∼100 K) 和高磁场 (9.4 T) 的固态DNP NMR实验.
- 根分布和根间距离的表征.
- 氨酸和酸溶液在DNP NMR中的应用.
主要成果:
- 使用含有TEMPO的材料,在≤100K和9.4T时达到高达36的增强因子.
- 证明同质的基因分布和最佳的基因度是高DNP增强的关键.
- 与单基和双基 (TEMPO,bTUrea) 均表现出成功的应用.
- 通过简单的过实现了从极化矩阵中分离分析物.
结论:
- 半孔混合-有机材料是固态DNPNMR的有效极化矩阵.
- 均的基因分布和受控的基因度对于最大化DNP增强至关重要.
- 这些材料为传统的DNP极化剂提供了有希望的替代品,简化了实验程序.
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