超过20%的 (15) N 超极化在不到一分钟的时间内,用于metronidazole,一种抗生素和低氧探针
Danila A Barskiy1, Roman V Shchepin1, Aaron M Coffey1
1Department of Radiology, Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center , Nashville, Tennessee 37232, United States.
Journal of the American Chemical Society
|June 21, 2016
概括
通过对来实现-15位点的直接NMR超极化. 这种方法将信号增强到100万倍,扩大了体内成像的超极化应用.
科学领域:
- 核磁共振 (NMR) 光谱学
- 超极化技术
- 医学成像
背景情况:
- 甲醇是治疗无氧细菌和原生动物感染的关键药物.
- 目前的核磁共振方法缺乏检测-15等低丰度同位素的灵敏度.
- 超极化显著增强了NMR信号,使实时分子成像成为可能.
研究的目的:
- 为了证明自然丰富的-15位点的直接NMR超极化.
- 扩大基于的超极化方法对多种分子结构的适用性.
- 在医学诊断中探索超极化甲醇的潜在应用.
主要方法:
- 使用SHIELD可逆交换信号放大使对齐转移到异质核 (SABRE-SHEATH) 技术.
- 用于有效的核自旋偏振.
- 使用各种自旋-自旋合 (J(nH) - ((15) N) 的直接结合和远离-15位点的超极化研究.
主要成果:
- 使用80%的H2可在几秒钟内达到高达24%的核旋转极化 (P(N).
- 预计P(15) N约为32%,100%为H2,在9.4 T时可实现约100万倍的信号增强.
- 在甲基中成功超极化直接结合和更远的-15位点.
结论:
- 在SABRE-SHEATH方法中,可以有效地实现-15的直接NMR超极化.
- 这种技术可以通过低成本的超极化来扩大分子和位置的范围.
- 超极化胺醇对药物机制的体内成像和低氧感应具有显著的前景.
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