Naganuma Tatsuya, Nakao Motonao, Ichikawa Kazuhiro, Utsumi Hideo
Japan REDOX Limited.
Yakugaku Zasshi. 2015;135(5):733-8. doi: 10.1248/yakushi.14-00235-3.
For indirect tissue observation, electron-spin, Overhauser-enhanced, dynamic nuclear polarization magnetic resonance imaging (DNP-MRI) is a useful technique. However, its sensitivity and resolution are low compared with the clinical MRI apparatus. By switching to electron spin resonance (ESR) excitation, the magnetic field of the NMR detection, field cycle technique, which aims to improve resolution, was proposed. However, the effect of eddy currents or current value was altered unsatisfactorily. A team at Kyushu University proposed a new DNP-MRI technique capable of improving NMR detection field by preparing in advance a magnetic field, which was connected by the sample transport system. By developing a mobile MRI method that can be used while moving, and fastening the sample in a disk that rotates at a constant speed, they have developed a circular transport DNP-MRI method that greatly reduces the load on the sample. The circular transport DNP-MRI system comprises a circular sample transport system, detection of an MRI magnetic field of 1.5 T, and ESR excitation magnetic field of 20 mT. The developed DNP-MRI had a clear glass tube phantom and resolution of 0.15 mm, and was successful in imaging multiple radical resonant points. It has been commercialized by Japan Redox Limited. In the process of equipment commercialization, a new digital spectrometer has been developed, which expanded the MRI apparatus.
对于间接组织观察，电子自旋、奥弗豪泽增强动态核极化磁共振成像（DNP-MRI）是一种有用的技术。然而，与临床MRI设备相比，其灵敏度和分辨率较低。通过切换到电子自旋共振（ESR）激发，提出了旨在提高分辨率的NMR检测磁场的场循环技术。然而，涡流或电流值的影响变化不尽人意。九州大学的一个团队提出了一种新的DNP-MRI技术，该技术能够通过预先准备由样品传输系统连接的磁场来提高NMR检测场。通过开发一种可以在移动时使用的移动MRI方法，并将样品固定在以恒定速度旋转的磁盘中，他们开发了一种圆形传输DNP-MRI方法，该方法大大减轻了样品的负担。圆形传输DNP-MRI系统包括圆形样品传输系统、1.5T的MRI磁场检测和20mT的ESR激发磁场。所开发的DNP-MRI具有清晰的玻璃管体模，分辨率为0.15mm，并成功地对多个自由基共振点进行了成像。它已由日本氧化还原有限公司商业化。在设备商业化过程中，开发了一种新的数字光谱仪，扩展了MRI设备。
