Them Kolja, Ellermann Frowin, Pravdivtsev Andrey N, Salnikov Oleg G, Skovpin Ivan V, Koptyug Igor V, Herges Rainer, Hövener Jan-Bernd
Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein and Kiel University, Am Botanischen Garten 14, 24118 Kiel, Germany.
International Tomography Center, SB RAS, 3A Institutskaya st., Novosibirsk 630090, Russia.
J Am Chem Soc. 2021 Sep 1;143(34):13694-13700. doi: 10.1021/jacs.1c05254. Epub 2021 Aug 18.
The hyperpolarization of nuclear spins is a game-changing technology that enables hitherto inaccessible applications for magnetic resonance in chemistry and biomedicine. Despite significant advances and discoveries in the past, however, the quest to establish efficient and effective hyperpolarization methods continues. Here, we describe a new method that combines the advantages of direct parahydrogenation, high polarization (), fast reaction, and low cost with the broad applicability of polarization transfer via proton exchange. We identified the system propargyl alcohol + pH → allyl alcohol to yield H polarization in excess of ≈ 13% by using only 50% enriched pH at a pressure of ≈1 bar. The polarization was then successfully relayed via proton exchange from allyl alcohol to various target molecules. The polarizations of water and alcohols (as target molecules) approached ≈ 1% even at high molar concentrations of 100 mM. Lactate, glucose, and pyruvic acid were also polarized, but to a lesser extent. Several potential improvements of the methodology are discussed. Thus, the parahydrogen-induced hyperpolarization relayed via proton exchange (PHIP-X) is a promising approach to polarize numerous molecules which participate in proton exchange and support new applications for magnetic resonance.
核自旋的超极化是一项改变游戏规则的技术，它使化学和生物医学中磁共振领域以前无法实现的应用成为可能。然而，尽管过去取得了重大进展和发现，但建立高效超极化方法的探索仍在继续。在这里，我们描述了一种新方法，该方法将直接仲氢加氢的优点、高极化率、快速反应和低成本与通过质子交换进行极化转移的广泛适用性相结合。我们确定了炔丙醇 + pH → 烯丙醇的体系，在约1巴的压力下仅使用50%富集的pH，就能产生超过约13%的H极化。然后，通过质子交换成功地将极化从烯丙醇传递到各种目标分子。即使在100 mM的高摩尔浓度下，水和醇（作为目标分子）的极化率也接近约1%。乳酸、葡萄糖和丙酮酸也被极化，但程度较小。讨论了该方法的几个潜在改进。因此，通过质子交换传递的仲氢诱导超极化（PHIP-X）是一种使众多参与质子交换的分子极化并支持磁共振新应用的有前途的方法。
