Zero- to Ultralow-Field NMR Spectroscopy of Small Biomolecules
Zero- to Ultralow-Field NMR Spectroscopy of Small Biomolecules
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DOI：
10.1021/acs.analchem.0c04738
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发表时间：
2021-01-15
影响因子：
7.4
通讯作者：
Barskiy, Danila A.
中科院分区：
文献类型：
--
作者：
Put, Piotr;Pustelny, Szymon;Barskiy, Danila A.
核磁共振（NMR）光谱是一种成熟的分析技术，用于研究化学物质及其转化。然而，高场核磁共振波谱需要先进的基础设施，即使是无低温的台式核磁共振波谱仪也不能轻易地从市售组件组装。我们展示了一个便携式零场核磁共振波谱仪的结构采用市售磁强计和研究其在分析化学中的应用。特别是，获得了具有代表性的小生物分子[C-13]-甲酸、[1-C-13]-甘氨酸、[2,3-C-13]-富马酸盐和[1-C-13]- d -葡萄糖的j -光谱，并研究了在检测过程中依赖横向磁场存在的松弛测量方法。我们发现，水弛豫时间在很大程度上取决于溶解d -葡萄糖的浓度，在1-10 mM的范围内，这为间接评估水溶液中的葡萄糖浓度提供了机会。将零场核磁共振的分析能力扩展到简单生物分子（氨基酸、糖和代谢物）的水溶液和葡萄糖水溶液的松弛研究，突出了无创便携式ZULF核磁共振传感器在研究实验室以外应用的分析潜力。
Nuclear magnetic resonance (NMR) spectroscopy is a well-established analytical technique used to study chemicals and their transformations. However, high-field NMR spectroscopy necessitates advanced infrastructure, and even cryogen-free benchtop NMR spectrometers cannot be readily assembled from commercially available components. We demonstrate construction of a portable zero-field NMR spectrometer employing a commercially available magnetometer and investigate its applications in analytical chemistry. In particular, J-spectra of small representative biomolecules [C-13]-formic acid, [1-C-13]-glycine, [2,3-C-13]-fumarate, and [1-C-13]-D-glucose were acquired, and an approach relying on the presence of a transverse magnetic field during the detection was investigated for relaxometry purposes. We found that the water relaxation time strongly depends on the concentration of dissolved D-glucose in the range of 1-10 mM suggesting opportunities for indirect assessment of glucose concentration in aqueous solutions. Extending analytical capabilities of zero-field NMR to aqueous solutions of simple biomolecules (amino acids, sugars, and metabolites) and relaxation studies of aqueous solutions of glucose highlights the analytical potential of noninvasive and portable ZULF NMR sensors for applications outside of research laboratories.