Division of Advanced Electronics and Optical Science, Department of Systems Innovation, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan.
Center for Quantum Information and Quantum Biology, Osaka University, 1-2 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
J Phys Chem Lett. 2023 Jul 13;14(27):6241-6247. doi: 10.1021/acs.jpclett.3c01002. Epub 2023 Jul 4.
Solution-state nuclear magnetic resonance spectroscopy (NMR) is a powerful method for the analysis of intermolecular interactions within a biomolecular system. However, low sensitivity is one of the major obstacles of NMR. We improved the sensitivity of solution-state C NMR for the observation of intermolecular interactions between protein and ligand using hyperpolarized solution samples at room temperature. Eutectic crystals composed of C-salicylic acid and benzoic acid doped with pentacene were hyperpolarized by dynamic nuclear polarization using photoexcited triplet electrons, and a C nuclear polarization of 0.72 ± 0.07% was achieved after dissolution. The binding of human serum albumin and C-salicylate was observed with several hundred times sensitivity enhancement under mild conditions. The established C NMR was applied for pharmaceutical NMR experiments by observation of the partial return of the C chemical shift of salicylate by competitive binding with other non-isotope-labeled drugs.
溶液态核磁共振波谱（NMR）是分析生物分子体系内分子间相互作用的有力方法。然而，灵敏度低是 NMR 的主要障碍之一。我们使用室温下超极化溶液样品提高了溶液态 C NMR 检测蛋白与配体之间相互作用的灵敏度。由掺杂五苯的水杨酸和苯甲酸组成的共晶通过光激发三重态电子进行动态核极化而超极化，溶解后 C 核极化度达到 0.72±0.07%。在温和条件下，通过与其他非同位素标记药物的竞争结合，观察到人血清白蛋白与水杨酸盐的结合，灵敏度提高了数百倍。通过与其他非同位素标记药物竞争结合，观察到水杨酸 C 化学位移的部分回复，建立的 C NMR 被应用于药物 NMR 实验。
