HR-MAS DREAMTIME NMR用于缓慢旋转的活体和活体样本
Rajshree Ghosh Biswas1, Wolfgang Bermel2, Amy Jenne1
1Environmental NMR Centre, University of Toronto, Toronto, ON M1C 1A4, Canada.
Analytical chemistry
|November 7, 2023
概括
DREAMTIME NMR是一种选择性技术,适用于HR-MAS NMR分析复杂样品. 一个新的版本,DREAMTIME-SLOWMAS,可以在完整的生物体中实现有针对性的代谢,克服光谱重叠的挑战.
科学领域:
- 分析化学 分析化学
- 生物化学 生物化学
- 频谱学是一种光谱学.
背景情况:
- 质子核磁共振 (1H NMR) 受到狭窄的光谱宽度的限制,导致复杂样品的重叠.
- 高分辨率神奇角度旋转 (HR-MAS) NMR允许对完整的异质样本进行分析,但面临光谱重叠问题.
- DREAMTIME NMR是一种选择性技术,用于从拥挤的光谱中分离代谢物,从而实现有针对性的代谢学.
研究的目的:
- 为HR-MAS应用适应选择性DREAMTIME NMR技术.
- 开发和验证DREAMTIME-SLOWMAS用于分析在缓慢旋转速度下完整的样品.
- 为了证明DREAMTIME和DREAMTIME-SLOWMAS在复杂的生物系统中针对目标代谢的实用性.
主要方法:
- 适应DREAMTIME NMR在各种旋转速度 (>5 kHz, 3-4 kHz, <2.5 kHz, ≤500 Hz) 的HR-MAS条件下.
- 介绍和测试DREAMTIME-SLOWMAS以解决水侧带在非常缓慢的旋转速度 (≤500 Hz) 的问题.
- 在无氧压力下对DREAMTIME和DREAMTIME-SLOWMAS进行比较分析,使用ex vivo虫组织和in vivo.
主要成果:
- 标准DREAMTIME NMR在HR-MAS条件下在旋转速度>2500 Hz或在D2O中的样品下有效地运行.
- DREAMTIME-SLOWMAS成功地将目标代谢物从完整的样本中以缓慢的旋转速度 (500 Hz) 隔离出来,而不会影响样本的完整性.
- 对活的DREAMTIME-SLOWMAS的应用揭示了与无氧压力相关的关键代谢物.
结论:
- DREAMTIME NMR是针对具有光谱重叠的复杂样本中的向代谢学的一个有价值的工具,适合HR-MAS应用.
- DREAMTIME-SLOWMAS扩展了DREAMTIME的适用性,以缓慢的旋转速度进行体内和完整组织分析,从而保持样本的完整性.
- 无论是DREAMTIME还是DREAMTIME-SLOWMAS,都为从具有挑战性的生物样本中准分子信息检索提供了强大的解决方案.
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