在水中溶解的窄线激素用于动态核极化
Olesya Haze1, Björn Corzilius, Albert A Smith
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|August 25, 2012
概括
研究人员开发了新的水溶性有机基因,用于动态核极化 (DNP). 这些基于BDPA的药物在NMR中提供了显著的灵敏度增强,推进了极化剂技术.
科学领域:
- 有机化学 有机化学
- 磁共振光谱学 磁共振光谱学
- 材料科学 材料科学 材料科学
背景情况:
- 动态核极化 (DNP) 使用极化剂增强NMR灵敏度.
- 现有的窄线极化剂,如三基,具有局限性.
- 开发稳定,水溶性有机基对于更广泛的DNP应用至关重要.
研究的目的:
- 为了合成和表征基于1,3-bis (二) - - 二 (BDPA) 核心的稳定在空气中的水溶性有机基.
- 评估硫衍生物 (SA-BDPA) 作为固体效应DNP (SE DNP) 的偏振剂的性能.
- 为了比较BDPA基激素与现有的三类型剂的疗效.
主要方法:
- 合成BDPA核心及其硫酸衍生物 (SA-BDPA).
- 电子偏磁共振 (EPR) 光谱法用于确定线宽.
- 固体效应动态核极化 (SE DNP) 实验.
- 高场魔术角度旋转 (MAS) 核磁共振 (NMR) 光谱仪用于提高灵敏度的测量.
主要成果:
- 成功合成了基于BDPA的稳定在空气中的,高度水溶性的有机基.
- 在缩溶液中,SA-BDPA证明了狭窄的EPR线宽 (<30MHz在5T).
- 在使用SA-BDPA的高场MAS NMR实验中获得了110的灵敏度增强.
- 基于BDPA的基因分子表现出易于合成和高最大增强.
结论:
- 基于BDPA的有机基,特别是SA-BDPA,是SE DNP的有效两极分化剂.
- 这些新型基因在合成和性能方面比三甲基类药物具有显著的优势.
- 开发的基因代表了高场NMR光谱学材料的重大进步.
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