King Jared N, Fallorina Alfredo, Yu Justin, Zhang Guannan, Telkki Ville-Veikko, Hilty Christian, Meldrum Tyler
Department of Chemistry , The College of William & Mary , Williamsburg , Virginia 23187-8795 , USA . Email:
Department of Chemistry , Texas A&M University , 3255 TAMU , College Station , Texas 77843 , USA.
Chem Sci. 2018 Jun 28;9(28):6143-6149. doi: 10.1039/c8sc01329b. eCollection 2018 Jul 28.
Laplace NMR (LNMR) offers deep insights on diffusional and rotational motion of molecules. The so-called "ultrafast" approach, based on spatial data encoding, enables one to carry out a multidimensional LNMR experiment in a single scan, providing from 10 to 1000-fold acceleration of the experiment. Here, we demonstrate the feasibility of ultrafast diffusion- relaxation correlation (-) measurements with a mobile, low-field, relatively low-cost, single-sided NMR magnet. We show that the method can probe a broad range of diffusion coefficients (at least from 10 to 10 m s) and reveal multiple components of fluids in heterogeneous materials. The single-scan approach is demonstrably compatible with nuclear spin hyperpolarization techniques because the time-consuming hyperpolarization process does not need to be repeated. Using dynamic nuclear polarization (DNP), we improved the NMR sensitivity of water molecules by a factor of 10 relative to non-hyperpolarized NMR in the 0.3 T field of the single-sided magnet. This enabled us to acquire a - map in a single, 22 ms scan, despite the low field and relatively low mole fraction (0.003) of hyperpolarized water. Consequently, low-field, hyperpolarized ultrafast LNMR offers significant prospects for advanced, mobile, low-cost and high-sensitivity chemical and medical analysis.
拉普拉斯核磁共振（LNMR）能深入洞察分子的扩散和旋转运动。基于空间数据编码的所谓“超快”方法，使人们能够在单次扫描中进行多维LNMR实验，将实验加速10到1000倍。在此，我们展示了使用移动、低场、相对低成本的单面核磁共振磁体进行超快扩散 - 弛豫相关（-）测量的可行性。我们表明该方法可以探测广泛的扩散系数范围（至少从10到10 m²/s），并揭示异质材料中流体的多个成分。单次扫描方法显然与核自旋超极化技术兼容，因为耗时的超极化过程无需重复。使用动态核极化（DNP），在单面磁体的0.3 T场中，我们将水分子的核磁共振灵敏度相对于非超极化核磁共振提高了10倍。尽管超极化水的场强低且摩尔分数相对较低（0.003），这仍使我们能够在单次22毫秒的扫描中获取一张 - 图谱。因此，低场、超极化的超快LNMR在先进、移动、低成本和高灵敏度的化学及医学分析方面具有广阔前景。
