储存的旋极化在长寿的13C2单元顺序和对高极化磁共振成像的影响
Yesu Feng1, Thomas Theis, Xiaofei Liang
1Department of Chemistry, Duke University, Durham, North Carolina 27708, USA.
Journal of the American Chemical Society
|June 21, 2013
概括
超极化磁共振成像 (MRI) 面临的挑战是信号衰减. 本研究展示了一种使用13C2-1,2-diphenylacetylene的方法,以显著延长旋转寿命,以增强代谢成像.
科学领域:
- 磁共振成像技术 磁共振成像技术
- 代谢学 代谢学 代谢学
- 量子信息科学 量子信息科学
背景情况:
- 超极化磁共振成像 (MRI) 在低度下提供实时代谢监测.
- 一个主要的限制是注射后T1超极化的快速衰变.
- 开发方法来延长超极化对于先进的MRI应用至关重要.
研究的目的:
- 为了研究A(n) A'(n) XX'旋转系统中的长寿命极化.
- 为了证明碳-13 ((13) C) 和-1 ((1) H) 旋转的延长旋转寿命.
- 探索在临床MRI扫描仪上实施这些技术的可行性.
主要方法:
- 使用 (13)C2-1,2-diphenylacetylene ((13)C2-DPA) 作为A(n) A'(n) XX'旋转系统的模型系统.
- 在高磁场 (高达16.44 T) 中测量了自旋寿命和衰变常数.
- 采用只有质子的脉冲序列用于极化存储和检索.
主要成果:
- 实现了 (13) C 和 (1) H 旋转的长寿命极化,衰变常数约为 4.5 分钟.
- 观察到质子极化的T1衰变仅为3.8秒.
- 通过存储偏振在 (13) C2-单点状态,证明了质子自旋寿命延长69倍.
结论:
- 像13C2-DPA这样的A'n'XX'旋转系统可以维持长期的极化.
- 将质子极化存储在 (13) C2-单片状态中,有效地延长了自旋寿命.
- 展示的仅为质子的脉冲序列与标准的临床MRI扫描仪兼容,为增强的超极化MRI铺平了道路.
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