In recent years, hyperpolarization of water protons via dissolution Dynamic Nuclear Polarization (dDNP) has attracted increasing interest in the magnetic resonance community. Hyperpolarized water may provide an alternative to Gd-based contrast agents for angiographic and perfusion Magnetic Resonance Imaging (MRI) examinations, and it may report on chemical and biochemical reactions and proton exchange while perfoming Nuclear Magnetic Resonance (NMR) investigations. However, hyperpolarizing water protons is challenging. The main reason is the presence of radicals, required to create the hyperpolarized nuclear spin state. Indeed, the radicals will also be the main source of relaxation during the dissolution and transfer to the NMR or MRI system. In this work, we report water magnetizations otherwise requiring a field of 10,000 T at room temperature on a sample of pure water, by employing dDNP via UV-generated, labile radicals. We demonstrate the potential of our methodology by acquiring a ¹⁵N spectrum from natural abundance urea with a single scan, after spontaneous magnetization transfer from water protons to nitrogen nuclei.

近年来，通过溶解动态核极化 (dDNP) 的水质子超极化引起了磁共振界越来越多的兴趣。超极化水可以替代基于 Gd 的造影剂，用于血管造影和灌注磁共振成像 (MRI) 检查，并且它可以在进行核磁共振 (NMR) 研究时报告化学和生化反应以及质子交换。然而，超极化水质子具有挑战性。主要原因是存在产生超极化核自旋态所需的自由基。事实上，自由基也将是溶解和转移到 NMR 或 MRI 系统期间松弛的主要来源。在这项工作中，我们报告了水磁化，否则需要 10 的场，000 T 在室温下对纯水样品，通过紫外线产生的不稳定自由基使用 dDNP。我们通过获得在自发磁化从水质子转移到氮原子核后，单次扫描来自天然丰度尿素的^{15 N 光谱。}