Solution-State High Field DNP on Large Volume Samples: Sensitivity-Enchanced NMR for the Organic Chemist

大体积样品的溶液态高场 DNP：有机化学家的灵敏度增强 NMR

• 批准号: 2203405
• 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: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2203405&HistoricalAwards=false
• 关键词: Solution; State; Field; DNP; Large

With support from the Chemical Measurement and Imaging (CMI) Program in the Division of Chemistry, Dr. Sungsool Wi and his team at the National High Magnetic Field Laboratory (NHMFL) at Florida State University are devising new methods to advance the capabilities of nuclear magnetic resonance (NMR) spectroscopy – a leading means of characterizing the structure and dynamics of organic molecules. Complementary innovative paths are being pursued to substantially improve the NMR sensitivity and to provide correspondingly lower limits of detection for a wider range of target molecules. If successful, these methods would provide new opportunities for characterizing molecules in many different areas of scientific and industrial applications, including studies of pharmaceuticals, metabolites in human and animal studies, natural products, food and polymer additives, and small molecules in natural crude oil. Tools developed will be made available to local and remote users of NHMFL. This project provides valuable training opportunities to participating student and postdoctoral trainees, including summer internships offering hands-on experience for undergraduate students. The Wi team has identified two independent, complementary approaches to enhancing the NMR signals of arbitrary molecules. One relies on the use of low-viscosity supercritical solvents to enable electron-to-nucleus Overhauser-based dynamic nuclear polarization (ODNP). The other relies on hitherto unknown relaxation processes arising in biradicals to enable transfers from two J-coupled electrons to one nucleus over a wide variety of fields and correlation times. The Wi group will leverage these technological and conceptual breakthroughs to enable sensitivity-enhanced DNP spectroscopy at high fields on ~100 μL solution-state samples containing dilute organic molecules, with the aim of potentially creating a new paradigm in NMR.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.

在化学系化学测量和成像（CMI）项目的支持下，佛罗里达州立大学国家高磁场实验室（NHMFL）的Sungsool Wi博士和他的团队正在设计新方法，以提高核磁共振（NMR）光谱的能力-这是表征有机分子结构和动力学的主要手段。正在寻求互补的创新途径，以大幅提高NMR灵敏度，并为更广泛的目标分子提供相应的较低检测限。 如果成功，这些方法将为表征许多不同科学和工业应用领域的分子提供新的机会，包括药物研究、人类和动物研究中的代谢物、天然产物、食品和聚合物添加剂以及天然原油中的小分子。开发的工具将提供给NHMFL的本地和远程用户。该项目为参与的学生和博士后学员提供了宝贵的培训机会，包括为本科生提供实践经验的暑期实习。Wi团队已经确定了两种独立的互补方法来增强任意分子的NMR信号。一种依赖于使用低粘度的超临界溶剂来实现基于电子到核的动态核极化（ODNP）。 另一个依赖于迄今为止未知的弛豫过程中产生的双自由基，使转移从两个J-耦合电子到一个核在各种各样的领域和相关时间。Wi小组将利用这些技术和概念上的突破，在高场条件下对含有稀释有机分子的~100 μL溶液态样品进行灵敏度增强的DNP光谱分析，旨在潜在地创建NMR的新范例。该奖项反映了NSF的法定使命，并通过使用基金会的知识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

Terahertz EPR spectroscopy using a 36-tesla high-homogeneity series-connected hybrid magnet

• DOI: 10.1016/j.jmr.2023.107480
• 发表时间: 2023-06-16
• 期刊: JOURNAL OF MAGNETIC RESONANCE
• 影响因子: 2.2
• 作者: Dubroca，Thierry;Wang，Xiaoling;Krzystek，J.
• 通讯作者: Krzystek，J.