Sensitivity-Enhanced High-Field Solution-State NMR by Gyrotron-Driven DNP

通过回旋管驱动的 DNP 进行灵敏度增强的高场溶液态 NMR

• 批准号: 1808660
• 负责人: Sungsool Wi
• 金额: $ 45万
• 依托单位: Florida State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-15 至 2022-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1808660&HistoricalAwards=false
• 关键词: Sensitivity; Enhanced; Field; Solution; State

Nuclear magnetic resonance (NMR) is one of the most important and widely used methods for characterizing molecular structure and dynamics, but its sensitivity - especially when applied to liquid samples - is inadequate for many important applications. With support from the Chemical Measurement & Imaging program in the Division of Chemistry, Drs. Sungsool Wi, Lucio Frydman, and Stephen Hill at Florida State University's National High Magnetic Field Laboratory (NHMFL) are working to achieve solution-state applicability for recent technological and conceptual breakthroughs that have dramatically improved the sensitivity of high-field NMR for characterization of solids. Extension to liquids (including aqueous solutions) may have transformative consequences in chemistry and biochemistry, particularly for characterizing limited quantities of small to medium-sized molecules. Potential applications include natural products and pharmaceutical chemistry; petroleum and polymer analytical chemistry; food and environmental sciences; and metabolomics. The NHMFL setting facilitates wide dissemination of the techniques, and provides accessibility to outside users in diverse application areas. It also enables extensive outreach efforts targeting high school students and involvement of undergraduates.The Wi group is developing solution-state Overhauser-enhanced dynamic nuclear polarization (ODNP) NMR for large volume samples ( 100 uL) at high magnetic fields (= 14.1 T/600 MHz), aiming to dramatically improve NMR sensitivity under typical conditions using conventional and cryogenically-cooled solution-state NMR probe heads. The research leverages the recent development of a high-power Gyrotron source operating at 395 GHz, with matching quasi-optical technologies, and a 600 MHz NMR solution-state spectrometer incorporating a customized NMR probe. These breakthroughs are being extended to a far wider range of organic analytes by employing new hardware which enables ODNP-enhanced double-resonance experiments in low-viscosity, low-dielectric-loss solvents such as hexane, in supercritical fluids, and using novel radical combinations. In situ EPR spectroscopy, executed in the same 600 MHz spectrometer and enabled through modifications to the existing quasioptical interface, is being employed to provide unique mechanistic insights and to further optimize these ODNP-enhanced NMR experiments.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

核磁共振 (NMR) 是表征分子结构和动力学的最重要和最广泛使用的方法之一，但其灵敏度（尤其是应用于液体样品时）不足以满足许多重要应用的需要。 在化学系化学测量和成像项目的支持下，博士。佛罗里达州立大学国家强磁场实验室 (NHMFL) 的 Sungsool Wi、Lucio Frydman 和 Stephen Hill 正在努力实现最新技术和概念突破的溶液态适用性，这些突破极大地提高了高场 NMR 用于固体表征的灵敏度。 扩展到液体（包括水溶液）可能会对化学和生物化学产生变革性的影响，特别是对于表征有限数量的中小分子。潜在应用包括天然产物和药物化学；石油和聚合物分析化学；食品和环境科学；和代谢组学。 NHMFL 设置促进了技术的广泛传播，并为不同应用领域的外部用户提供了可访问性。 它还能够针对高中生和本科生进行广泛的推广工作。Wi 小组正在开发适用于高磁场 (= 14.1 T/600 MHz) 下大体积样品 (100 uL) 的溶液态 Overhauser 增强动态核极化 (ODNP) NMR，旨在使用传统和低温冷却溶液态 NMR 在典型条件下显着提高 NMR 灵敏度 探头。该研究利用了最新开发的工作频率为 395 GHz 的高功率回旋管源以及匹配的准光学技术，以及包含定制 NMR 探头的 600 MHz NMR 溶液态光谱仪。这些突破正在扩展到更广泛的有机分析物，通过采用新硬件，可以在低粘度、低介电损耗溶剂（如己烷）、超临界流体中进行 ODNP 增强双共振实验，并使用新颖的自由基组合。原位 EPR 光谱在同一 600 MHz 光谱仪中执行，并通过修改现有准光学接口实现，用于提供独特的机械见解并进一步优化这些 ODNP 增强的 NMR 实验。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Large volume liquid state scalar Overhauser dynamic nuclear polarization at high magnetic field

• DOI: 10.1039/c9cp02997d
• 发表时间: 2019-10-14
• 期刊: PHYSICAL CHEMISTRY CHEMICAL PHYSICS
• 影响因子: 3.3
• 作者: Dubroca, Thierry;Wi, Sungsool;Hill, Stephen
• 通讯作者: Hill, Stephen

High-field solution state DNP using cross-correlations

• DOI: 10.1016/j.jmr.2021.106940
• 发表时间: 2021-04-14
• 期刊: JOURNAL OF MAGNETIC RESONANCE
• 影响因子: 2.2
• 作者: Concilio, Maria Grazia;Soundararajan, Murari;Kuprov, Ilya
• 通讯作者: Kuprov, Ilya