磁性多金属氧簇超分子复合物的制备及多功能成像特性

Magnetic resonance imaging contrast agent is an important part of the magnetic resonance imaging technology which are used widely in the medical field. Commercial magnetic resonance imaging contrast agents are generally chelates containing gadolinium or manganese ions, the smaller size of these compounds lead to its flip faster in the solution, which reduce the imaging effect. In addition, this type of compounds is generally on a single function. So, how to improve the efficiency of imaging and develop the multi-functionality of contrast agents became an important scientific problem of medical imaging research. This research project aims to prepare paramagnetic metal substituted polyoxometalates as inorganic core, and to synthesize surfactant containing mesogens cluster as the organic shell. Through electrostatic interaction, two components combine to form supramolecular complexes. The stability of the complexes in aqueous solution and controlled aggregation features make it possible to further explore its magnetic resonance imaging effects.This system has the following advantages:1.the polyoxometalates can combine with different number of magnetic metal ions which would provide more than one magnetic centers. In addition, the complex will aggregate in the solution and make a larger size. The two aspects both help to improve the imaging effect;2. the complexes with the mesogens can be used for fluorescence imaging and in vivo localization.

磁共振造影剂是在医学领域有广泛应用的磁共振成像技术的重要组成部分，目前商用的磁共振造影剂一般都是采用钆或锰的小分子螯合物。此类化合物较小的体积导致其在溶液中翻转速度较快，从而降低了成像效果，同时这类化合物基本上都是单一功能的。如何提高成像效率以及发展具有多功能的造影剂一直是医学影像学研究的重要科学问题。本研究项目拟计划以顺磁性金属取代的多金属氧簇为无机核心，以含有发光基团的表面活性剂为有机外壳，通过静电作用，将二者结合起来，形成超分子复合物。利用复合物在水溶液中的稳定性以及可控聚集的特点，进一步探索其作为磁共振造影剂的成像效果。在成像方面，本体系具有如下优点：1.多金属氧簇可以结合不同数量的磁性金属离子，提供多个磁性中心，同时复合物在溶液中会发生聚集，使其具有较大体积，这两方面都有利于提高成像效果。2.由于复合物中带有发光基团，可以用于荧光成像以及造影剂在体内的定位。