Development of hyperpolarized solid state NMR spectroscopy

描述（由申请人提供）：NMR是科学和医学中不可或缺的工具。然而，由于核的磁矩小，因此塞曼能量分裂小，NMR的灵敏度不太具有竞争力。本研究的目的是开发新的超极化技术的固态核磁共振光谱可在室温下与一般的固态生物材料。 目前，在固体核磁共振中产生增强核极化的最主要方法是利用回旋管的动态核极化（DNP）。DNP是电子极化转移到原子核的过程;因此，预期通过旋磁比（γ/γ N ~658（1H））确定的NMR信号的最大理论增强。我们的新方法采用光学核极化技术（光激发，随后三重态猝灭的稳定自由基和转移的电子极化的核）。由于光激发是一个非热过程，NMR信号增强可以大大超过传统的DNP上限（γ/γ N）。 在成功开发该技术后，我们期望提供以下对固态NMR现状的改进：1）测量时间的显著减少（这将导致更高分子量生物聚合物的研究），2）改进的检测限，和3）在环境样品条件下在高温下的超极化。在许多研究领域中，可以受益于增强的灵敏度，我们预计组织代谢组学和代谢研究与活检将受到很大的影响。

DESCRIPTION (provided by applicant): NMR is an indispensable tool in science and medicine. The sensitivity of NMR, however, is less competitive due to small magnetic moments of nuclei and thus small Zeeman energy splitting. The goal of this research is to develop novel hyperpolarization techniques for solid state NMR spectroscopy operable at room temperature with general solid state biomaterials. Currently, the most prominent way to generate enhanced nuclear polarization in solid state NMR is dynamic nuclear polarization (DNP) with gyrotrons. DNP is a process that electron polarization is transferred to nuclei; therefore maximum theoretical enhancement of NMR signal determined by gyromagnetic ratio, gammae/gammaN~658 for 1H), is expected. Our new approach employs optical nuclear polarization technique (optical excitation, subsequently triplet state quenching by stable radical and the transfer of electron polarization to nuclei). Since the optical excitation is a non-thermal process, NMR signal enhancement can greatly exceed the traditional DNP ceiling (gammae/gammaN). Upon successful development of this technique, we expect to provide the following improvements over the current status of solid state NMR: 1) significant reduction in measurement time (which will lead to the study of higher molecular weight biopolymers), 2) improved detection limit, and 3) hyperpolarization at high temperature in an ambient sample condition. Among many research areas that can benefit from enhanced sensitivity, we expect the tissue metabolomics and metabolism study with biopsy will be greatly influenced.