Synthesis in aqueous solution and characterisation of a new cobalt-doped ZnS quantum dot as a hybrid ratiometric chemosensor.
Synthesis in aqueous solution and characterisation of a new cobalt-doped ZnS quantum dot as a hybrid ratiometric chemosensor.
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DOI：
10.1016/j.aca.2011.09.044
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发表时间：
2011-12
影响因子：
6.2
通讯作者：
Wen-sheng Zou;Jun-qin Qiao;Xin Hu;Xin Ge;H. Lian
中科院分区：
文献类型：
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作者：
Wen-sheng Zou;Jun-qin Qiao;Xin Hu;Xin Ge;H. Lian
在本文中，钴（Co 2+）掺杂（CoD）的ZnS量子点（量子点）在水溶液中合成和表征的第一次。CoD ZnS量子点表面的半胱氨酸（l-Cys）配体可以与2，4，6-三硝基甲苯（TNT）结合形成Meisenheimer络合物（MHCs），主要是通过l-Cys与TNT之间的酸碱配对作用以及l-Cys分子间的氢键和静电相互作用。量子点在水溶液中的光散射特性受MHC诱导的点间聚集的影响很大，在紫外光激发下，CoD ZnS量子点在缺陷相关的发射波长及其左侧都出现了瑞利散射（RS）增强。RS增强，结合由TNT阴离子引起的橙子跃迁发射的淬灭，导致在比率可视化的系统正在调查的变化。因此，一种新的CoD ZnS量子点为基础的混合比例化学传感器已被开发用于简单和灵敏的分析水中的TNT。这种比率探针可以测定溶液中低至25 nM的TNT，而不会受到真实的水样和其他硝基芳香化合物基质的干扰。由于CoD ZnS量子点表面具有良好的电子接受能力和TNT对l-Cys的强亲和力，因此本文报道的CoD光致发光纳米材料非常适合于检测超痕量TNT和区分水溶液中的不同硝基化合物。
In this paper, cobalt (Co2+)-doped (CoD) ZnS quantum dots (QDs) are synthesised in aqueous solution and characterised for the first time. l-Cysteine (l-Cys) ligands on the surface of CoD ZnS QDs can bind 2,4,6-trinitrotoluene (TNT) to form Meisenheimer complexes (MHCs) mainly through acid–base pairing interactions between TNT and l-Cys and the assistance of hydrogen bonding and electrostatic co-interactions among l-Cys intermolecules. The aggregation of inter-dots induced by MHCs greatly influenced the light scattering property of the QDs in aqueous solution, and Rayleigh scattering (RS) enhancement at the defect-related emission wavelengths as well as its left side was observed with the excitation of CoD ZnS QDs by violet light. RS enhancement, combining with the quenching of the orange transition emission induced by TNT anions, resulted in a change in the ratiometric visualisation of the system being investigated. A novel CoD ZnS QD-based hybrid ratiometric chemosensor has therefore been developed for simple and sensitive analysis of TNT in water. This ratiometric probe can assay down to 25nM TNT in solution without interference from a matrix of real water sample and other nitroaromatic compounds. Because of the excellent electron-accepting ability and strong affinity of TNT to l-Cys on the surface of CoD ZnS QDs, the CoD photoluminescent nanomaterials reported here are well suited for detecting ultra-trace TNT and for distinguishing different nitro-compounds in aqueous solution.