A Molecular Imaging Approach to Mercury Sensing Based on Hyperpolarized 129Xe Molecular Clamp Probe
A Molecular Imaging Approach to Mercury Sensing Based on Hyperpolarized 129Xe Molecular Clamp Probe
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DOI：
10.1002/chem.201600193
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发表时间：
2016-03-14
影响因子：
4.3
通讯作者：
Zhou, Xin
中科院分区：
文献类型：
--
作者：
Guo, Qianni;Zeng, Qingbin;Zhou, Xin
以汞离子（Hg 2+）形式存在的汞污染是一种主要的健康和环境危害。常用的传感器是侵入式的，并且仅限于点测量。基于双折射的传感器不提供成像空间分布所需的深度分辨率。在这里，我们报告了一种新的传感器，能够产生空间分布的MRI使用超极化的α-129。以二吡咯基喹喔啉（DPQ）衍生物为探针分子，设计了一种新型的分子钳探针。DPQ衍生物充当阳离子受体，而隐啡烷-A充当氙的合适主体分子。当DPQ部分与汞离子相互作用时，分子钳在离子上闭合。由于两个隐黄素-A笼的电子云的重叠，对封装的隐黄素的屏蔽作用变得重要。这导致了封装的电子束的化学位移的高场变化。该传感器对汞离子具有良好的选择性和灵敏度。这种汞激活的超极化的Hg 129化学传感器是一种新概念的方法，通过MRI监测Hg 2+离子的分布。
Mercury pollution, in the form of mercury ions (Hg2+), is a major health and environmental hazard. Commonly used sensors are invasive and limited to point measurements. Fluorescence-based sensors do not provide depth resolution needed to image spatial distributions. Herein we report a novel sensor capable of yielding spatial distributions by MRI using hyperpolarized Xe-129. A molecular clamp probe was developed consisting of dipyrrolylquinoxaline (DPQ) derivatives and twocryptophane-A cages. The DPQ derivatives act as cation receptors whereas cryptophane-A acts as a suitable host molecule for xenon. When the DPQ moiety interacts with mercury ions, the molecular clamp closes on the ion. Due to overlap of the electron clouds of the two cryptophane-A cages, the shielding effect on the encapsulated Xe becomes important. This leads to an upfield change of the chemical shift of the encapsulated Xe. This sensor exhibits good selectivity and sensitivity toward the mercury ion. This mercury-activated hyperpolarized Xe-129-based chemosensor is a new concept method for monitoring Hg2+ ion distributions by MRI.