镧系金属螯合物作为CEST磁共振造影剂的研究进展

Research progress of lanthanide metal chelates as CESTMRI contrast agents

化学交换饱和转移(CEST)成像是一种基于化学位移现象的新型磁共振成像(MRI),通过检测水质子信号变化来间接测定可交换质子的信息,而镧系金属螯合物的顺磁化学位移大,质子共振位移更远离水的信号,可实现更多的选择性饱和,提高MRI的对比性,因此非常适合用作CEST造影剂.镧系金属螯合物CEST造影剂具有进一步扩展磁共振功能和分子成像的巨大潜力,文章主要介绍了此类物质的类型及应用.

Chemical exchange saturation transfer(CEST)imaging is a novel magnetic resonance imaging(MRI)method based on the phenomenon of chemical shift.The information of exchangeable protons can be indirectly determined by detecting the change of water proton signal.The lanthanide metal chelates have large paramagnetic chemical shifts and their proton resonance shifts are farther away from the water signal,which is feasible to achieve more selective saturation and improve the contrast of MRI.Therefore,the lanthanide metal chelates are very suitable as CEST contrast agents and have great potentials in further expanding their magnetic resonance function and molecular imaging capabilities.This review mainly summarizes the types and applications of the lanthanide metal chelates as CEST MRI contrast agents.