Kunth Martin, Witte Christopher, Schröder Leif
Molecular Imaging, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Campus Berlin-Buch, Robert-Roessle-Str. 10, 13125 Berlin, Germany.
Translational Molecular Imaging, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
Pharmaceuticals (Basel). 2021 Jan 21;14(2):79. doi: 10.3390/ph14020079.
Xenon magnetic resonance imaging (MRI) provides excellent sensitivity through the combination of spin hyperpolarization and chemical exchange saturation transfer (CEST). To this end, molecular hosts such as cryptophane-A or cucurbit[]urils provide unique opportunities to design switchable MRI reporters. The concentration determination of such xenon binding sites in samples of unknown dilution remains, however, challenging. Contrary to H CEST agents, an internal reference of a certain host (in this case, cryptophane-A) at micromolar concentration is already sufficient to resolve the entire exchange kinetics information, including an unknown host concentration and the xenon spin exchange rate. Fast echo planar imaging (EPI)-based Hyper-CEST MRI in combination with Bloch-McConnell analysis thus allows quantitative insights to compare the performance of different emerging ultra-sensitive MRI reporters.
通过自旋超极化与化学交换饱和转移（CEST）相结合，氙磁共振成像（MRI）具有出色的灵敏度。为此，诸如穴番-A或葫芦脲等分子主体为设计可切换的MRI报告分子提供了独特的机会。然而，在未知稀释度的样品中确定此类氙结合位点的浓度仍然具有挑战性。与氢CEST试剂不同，微摩尔浓度的特定主体（在这种情况下为穴番-A）的内部参考已经足以解析整个交换动力学信息，包括未知的主体浓度和氙自旋交换率。因此，基于快速回波平面成像（EPI）的超CEST MRI与布洛赫-麦康奈尔分析相结合，能够进行定量分析，以比较不同新型超灵敏MRI报告分子的性能。
