Electron-Spin Resonance Spectroscopy, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
Department of Chemistry, Georg-August-University, Tammannstraβe 4, 37077 Göttingen, Germany.
Nat Chem. 2017 Jul;9(7):676-680. doi: 10.1038/nchem.2723. Epub 2017 Feb 13.
Nuclear magnetic resonance (NMR) is a fundamental spectroscopic technique for the study of biological systems and materials, molecular imaging and the analysis of small molecules. It detects interactions at very low energies and is thus non-invasive and applicable to a variety of targets, including animals and humans. However, one of its most severe limitations is its low sensitivity, which stems from the small interaction energies involved. Here, we report that dynamic nuclear polarization in liquid solution and at room temperature can enhance the NMR signal of C nuclei by up to three orders of magnitude at magnetic fields of ∼3 T. The experiment can be repeated within seconds for signal averaging, without interfering with the sample magnetic homogeneity. The method is therefore compatible with the conditions required for high-resolution NMR. Enhancement of C signals on various organic compounds opens up new perspectives for dynamic nuclear polarization as a general tool to increase the sensitivity of liquid NMR.
核磁共振（NMR）是研究生物系统和材料、分子成像以及小分子分析的基本光谱技术。它检测非常低能量的相互作用，因此是非侵入性的，适用于各种目标，包括动物和人类。然而，它最严重的限制之一是灵敏度低，这源于所涉及的小相互作用能量。在这里，我们报告在液态溶液和室温下的动态核极化可以在约 3 T 的磁场中将 C 核的 NMR 信号增强高达三个数量级。该实验可以在不干扰样品磁场均匀性的情况下在几秒钟内重复进行信号平均。因此，该方法与高分辨率 NMR 所需的条件兼容。各种有机化合物上 C 信号的增强为动态核极化作为提高液体 NMR 灵敏度的通用工具开辟了新的前景。
