Pulse-Programmable Magnetic Field Sweeping of Parahydrogen-Induced Polarization by Side Arm Hydrogenation
Pulse-Programmable Magnetic Field Sweeping of Parahydrogen-Induced Polarization by Side Arm Hydrogenation
复制标题
DOI：
10.1021/acs.analchem.9b04501
复制
发表时间：
2020-01-07
影响因子：
7.4
通讯作者：
Chekmenev, Eduard Y.
中科院分区：
文献类型：
--
作者：
Joalland, Baptiste;Schmidt, Andreas B.;Chekmenev, Eduard Y.
在面向体内磁共振成像的超极化技术中，对氢诱导极化（PHIP）因其成本低、造影剂制备速度快而被看好。通过侧臂氢化合成C-13标记的不饱和前体来进行PHIP，由于反应产物的生物相容性，最近为代谢成像开辟了新的可能性，尽管对氢衍生的质子和C-13异核之间的极化转移还必须更好地理解、表征和最终优化。在这一领域，一种结合脉冲可编程磁场扫描和原位探测的新实验策略已经被开发出来。该方法通过测量醋酸乙酯-1-C-13的C-13极化来评估，即对氢对醋酸乙烯-1-C-13的成对加成产物，由不同持续时间、振幅和步长的零交叉磁场斜坡产生。结果表明：(1)这些参数对H-1到C-13的极化传递效率有深远的影响；(2)该技术的高重复性。
Among the hyperpolarization techniques geared toward in vivo magnetic resonance imaging, parahydrogen-induced polarization (PHIP) shows promise due to its low cost and fast speed of contrast agent preparation. The synthesis of C-13-labeled, unsaturated precursors to perform PHIP by side arm hydrogenation has recently opened new possibilities for metabolic imaging owing to the biological compatibility of the reaction products, although the polarization transfer between the parahydrogen-derived protons and the C-13 heteronucleus must yet be better understood, characterized, and eventually optimized. In this realm, a new experimental strategy incorporating pulse-programmable magnetic field sweeping and in situ detection has been developed. The approach is evaluated by measuring the C-13 polarization of ethyl acetate-1-C-13, i.e., the product of pairwise addition of parahydrogen to vinyl acetate-1-C-13, resulting from zero-crossing magnetic field ramps of various durations, amplitudes, and step sizes. The results demonstrate (i) the profound effect these parameters have on the H-1 to C-13 polarization transfer efficiency and (ii) the high reproducibility of the technique.