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微特斯拉SABRE使10%的-15核旋极化成为可能
Thomas Theis1, Milton L Truong, Aaron M Coffey
1Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
Journal of the American Chemical Society
|January 14, 2015
概括
过能有效地将-15超极化到皮里丁和尼古丁胺中,使用磁盾中的"可逆交换信号放大" (SABRE). 这种"SABRE in shield enables alignment transfer to heteronuclei" (SABRE-SHEATH) 方法为各种应用提供了具有成本效益的超极化.
科学领域:
- 核磁共振 (NMR) 光谱学 核磁共振 (NMR) 光谱学
- 量子化学 是一个量子化学.
- 生物物理学的生物物理.
背景情况:
- 超极化技术显著提高了NMR信号的灵敏度.
- -15 (15N) 是分子成像和代谢研究的关键核.
- 目前的超极化方法可能是复杂和昂贵的.
研究的目的:
- 在生物相关分子中证明-15的高效核旋转超极化.
- 为了引入一种新的,具有成本效益的超极化方法.
- 探索这种技术在体内应用中的潜力.
主要方法:
- 在微特斯拉场上利用和"可逆交换信号放大" (SABRE).
- 在磁盾内执行SABRE,以实现高效的旋转极化转移.
- 将高极化样本转移到常规的NMR光谱仪以检测信号.
主要成果:
- 在15NNNMR信号中分别实现了约30,000倍和约20,000倍的提升,分别是皮里丁和尼古丁胺胺.
- 在9.4 T时,达到里丁和尼古丁胺的核旋极化值为∼10%和∼7%的核旋极化.
- 证明了"SABRE in shield enabling alignment transfer to heteronuclei" (SABRE-SHEATH) 方法的有效性. 这是一个非常好的方法.
结论:
- SABRE-SHEATH提供了一种简单且具有成本效益的方法,用于超极化像 (15) N. 之类的异极核.
- 该方法为体内NMR/MRI提供了潜在的优势,因为它具有很长的超极化寿命和最小的背景信号.
- 易于对不同物种进行化学转移歧视,提高了它对生物研究的有用性.
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