Pravdivtsev Andrey N, Hövener Jan-Bernd
Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel University, Am Botanischen Garten 14, 24118, Kiel, Germany.
Chemistry. 2019 Jun 7;25(32):7659-7668. doi: 10.1002/chem.201806133. Epub 2019 Mar 28.
The hyperpolarization of nuclear spins by using parahydrogen (pH ) is a fascinating technique that allows spin polarization and thus the magnetic resonance signal to be increased by several orders of magnitude. Entirely new applications have become available. Signal amplification by reversible exchange (SABRE) is a relatively new method that is based on the reversible exchange of a substrate, catalyst and parahydrogen. SABRE is particularly interesting for in vivo medical and industrial applications, such as fast and low-cost trace analysis or continuous signal enhancement. Ever since its discovery, many attempts have been made to model and understand SABRE, with various degrees of simplifications. In this work, we reduced the simplifications further, taking into account non-linear chemical and physical (CAP) dynamics of several multi-spin systems. A master equation was derived and realized using the MOIN open-source software. The effects of different parameters (exchange rates, concentrations, spin-spin couplings) on relaxation and the polarization level have been evaluated and the results provide interesting insights into the mechanism of SABRE.
利用仲氢（pH）使核自旋超极化是一项引人入胜的技术，它能使自旋极化，进而使磁共振信号增强几个数量级。全新的应用由此得以实现。通过可逆交换实现信号放大（SABRE）是一种相对较新的方法，它基于底物、催化剂和仲氢之间的可逆交换。SABRE在体内医学和工业应用中尤其具有吸引力，例如快速且低成本的痕量分析或连续信号增强。自其被发现以来，人们进行了许多尝试来对SABRE进行建模和理解，简化程度各不相同。在这项工作中，我们进一步减少了简化，考虑了几个多自旋系统的非线性化学和物理（CAP）动力学。使用MOIN开源软件推导并实现了一个主方程。评估了不同参数（交换速率、浓度、自旋 - 自旋耦合）对弛豫和极化水平的影响，结果为SABRE的机制提供了有趣的见解。
