生物相容性币金属纳米团簇的制备、结构表征及其在检测“活性硫物种”中的应用

Organic fluorescence reagents are widely used in every aspect, but there are problems with the difficulties in preparation, high cytotoxicity, low biocompatibility and the interference of background fluorescence in fluorimetry. According to the rule that the character change of the periphery ligand may lead to the modification of the whole coinage metal nanoclusters, this project try to design and synthesis the cytidine-protected coinage metal nanocluster to transform their biocompatibility and chirality. The convenience method are explored for the preparation of stable coinage metal nanoclusters and a new method for the physiological detection of reactive sulfur species (RSS) by circular dichroism spectra (CD) is developed. The target clusters will be characterized by single-crystal X-ray diffraction, NMR, MS, EA and IR. The relationship between their molecular structures and properties will be studied. The special CD properties of coinage metal nanoclusters could be used for the detection of RSS with CD signal alterations. The rules and mechanism of the interaction between them proposed in line with the experimental results will be felt out. The results will further reveal the surface and the interface of coinage metal nanoclusters and provide a new CD analysis method based on the cytidine-protected silver nanocluster, which can free fluorometry from the constraint that the used compound must be luminous. And it also helps to provide a new solution for the interference problem of background in the physiological detection of RSS.

针对目前广泛使用的有机荧光试剂合成复杂、细胞毒性大、生物相容性低，同时在荧光分析法中还存在背景荧光的干扰等难点、热点问题，本项目参照配体性质的变化引起币金属纳米团簇性质的改变这一规律，拟设计、合成以胞嘧啶核苷为配体保护的具有生物相容性和手性的币金属纳米团簇，发展圆二色谱检测“活性硫物种”的新手段。采用X-ray单晶衍射、核磁共振、质谱、元素分析及红外光谱等方法对目标团簇进行结构表征后，研究其结构与性能的相关关系，再结合其在检测“活性硫物种”过程中溶液圆二色信号的变化，提出与实验结果一致的作用机理。以上成果将进一步揭示币金属纳米团簇的界表面结构，摆脱荧光分析法必须基于发光化合物的限制，建立起基于银纳米团簇的圆二色光谱分析法，为解决生理条件下检测“活性硫物种”的过程中背景干扰问题提供新的思路和方案。

参照配体性质的变化引起币金属团簇性质改变的相关规律，本项目研究内容主要集中在设计、构筑币金属簇合物及其性能研究方面。在本项目执行期内，通过利用胞嘧啶、二茂铁衍生物等生物相关的配体一系列具有生物相容、氧化还原等性质的铜/银簇合物被制备，在表征其结构的同时，重点研究其在小分子检测电极材料、发光材料、光催化降解、能量存储电极材料等方面的潜在应用。我们不仅利用币金属功能配合物作为电化学检测电极材料实现了双氧水的快速灵敏检测，而且还利用其作为光催化剂实现了有机染料亚甲基蓝的可见光快速降解(20分钟内的降解率为15000 mg.g-1)。此外，我们发现将币金属的配位聚合物作为超级电容器的电极材料，不仅具有优异的倍率电容性能、循环稳定性(4000次97 %)，而且具有高的比电容量927 Fg-1、功率密度(1448 Wkg−1)和能量密度(39.18 Wh kg−1)。相关研究结果为币金属功能配合物的结构设计和性能优化提供了实验依据，为发展其相关应用奠定了基础。