Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Kiel, Kiel University, Kiel, Germany.
Faculty of Mathematics and Natural Sciences, Chemistry Section, Kiel University, Kiel, Germany.
J Magn Reson. 2018 Dec;297:86-95. doi: 10.1016/j.jmr.2018.10.006. Epub 2018 Oct 10.
The hyperpolarization of nuclear spins using parahydrogen is an interesting effect that allows to increase the magnetic resonance signal by several orders of magnitude. Known as ParaHydrogen And Synthesis Allow Dramatically Enhanced Nuclear Alignment (PASADENA) and ParaHydrogen Induced Polarization (PHIP), the method was successfully used for in vitro analysis and in vivo imaging. In this contribution, we investigated four known and four new variants of Only Parahydrogen SpectroscopY (OPSY) sequences (Aguilar et al., 2007) with respect to the selective preparation of hyperpolarized NMR signal and background suppression. Depending on the method chosen, either anti-phase, in-phase or a mixture of both signals are obtained: anti-phase signals are beneficial to identify hyperpolarized signals and the structure or J-coupling constants; in-phase signals are useful for imaging applications or when the lines are broad. This comprehensive overview of sequences new and old facilitates selecting the right sequence for the task at hand.
利用仲氢实现核自旋的极化是一种有趣的效应，可将磁共振信号增强几个数量级。这种方法被称为 ParaHydrogen And Synthesis Allow Dramatically Enhanced Nuclear Alignment (PASADENA) 和 ParaHydrogen Induced Polarization (PHIP)，已成功用于体外分析和体内成像。在本研究中，我们研究了四种已知和四种新的 Only Parahydrogen SpectroscopY (OPSY) 序列（Aguilar 等人，2007），以选择性制备高极化 NMR 信号和背景抑制。根据所选方法，可得到反相、同相或两者的混合信号：反相信号有助于识别高极化信号及其结构或 J 耦合常数；同相信号适用于成像应用或当谱线较宽时使用。本序列新老方法的全面概述有助于为手头的任务选择合适的序列。
