Improving NMR and MRI sensitivity with parahydrogen.
Improving NMR and MRI sensitivity with parahydrogen.
复制标题
使用仲氢提高 NMR 和 MRI 灵敏度。
DOI：
10.1007/128_2012_388
复制
发表时间：
2013
影响因子：
8.6
通讯作者：
Duckett SB
中科院分区：
文献类型：
--
作者：
Duckett SB
仲氢诱导极化 (PHIP) 在 NMR 和 MRI 中具有广泛的用途，因为它可以提高这两种技术的灵敏度。分析物中自旋顺序从仲氢到原子核的转移导致射频脉冲询问后磁响应增强。这种自旋转移由均相或多相催化剂催化。增强的磁响应不仅减少了获得光谱或图像所需的瞬态数量，而且还可以照亮溶液中以前无法检测到的物质。从理论预测到实验验证，PHIP 已应用于一系列不同领域，例如复合物的结构分析、了解涉及氢的反应机制以及生产 MRI 中使用的造影剂。 PHIP 还可以很容易地与光化学等其他技术相结合，从而拓宽了其应用领域。在这篇综述中，我们详细介绍了仲氢的性质及其在均相和非均相氢化和非氢化反应中的制备和利用方法。举例说明了PHIP在光化学和氢甲酰化反应中的应用。描述了设计为与 PHIP 兼容的脉冲序列，以举例说明如何通过最佳地询问磁状态来进一步提高灵敏度。最后，讨论了 PHIP 在生产适用于 MRI 的造影剂中的使用，以及使用成像技术监测氢化反应。
Parahydrogen induced polarisation (PHIP) has wide utility in NMR and MRI as it can increase the sensitivity of both techniques. The transfer of spin order fromparahydrogen to nuclei in the analyte leads to an increased magnetic response following interrogation by RF pulses. This spin transfer is catalysed by a homogeneous or heterogeneous catalyst. The increased magnetic response not only reduces the number of transients required to obtain the spectrum or image, but can also illuminate previously undetectable species present in solution. From its theoretical prediction to its experimental validation, PHIP has been applied in a range of different areas such as the structural analysis of complexes, understanding reaction mechanisms involving hydrogen and for the production of contrast agents for use in MRI. PHIP can also be readily combined with other techniques such as photochemistry which widens its field of applicability. In this review, we detail the properties ofparahydrogen and the methods for its preparation and utilisation in homogeneous and heterogeneous based hydrogenation and non-hydrogenative reactions. Specific examples are explained for the application of PHIP in photochemical and hydroformylation reactions. Pulse sequences designed to be compatible with PHIP are described to exemplify how the increase in sensitivity can be increased even further by the interrogation of the magnetic states optimally. Finally, a section on the use of PHIP in the production of contrast agents suitable for MRI, and the monitoring of hydrogenation reactions using imaging techniques is discussed.