Surface modification of silica nanoparticles: a new strategy for the realization of self-organized fluorescence chemosensors
Surface modification of silica nanoparticles: a new strategy for the realization of self-organized fluorescence chemosensors
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DOI：
10.1039/b502052b
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发表时间：
2005-07
影响因子：
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通讯作者：
E. Rampazzo;E. Brasola;Silvia Marcuz;F. Mancin;P. Tecilla;U. Tonellato
中科院分区：
文献类型：
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作者：
E. Rampazzo;E. Brasola;Silvia Marcuz;F. Mancin;P. Tecilla;U. Tonellato
荧光化学传感器的适当亚基在二氧化硅纳米颗粒表面的自组织允许新的有效的传感系统的容易的设计和实现。市售的二氧化硅颗粒（20 nm直径）官能化的三乙氧基硅烷衍生物的选择性Cu（II）配体和荧光染料。将传感器组分接枝到颗粒表面确保了传感器组分之间的空间接近性，因此，配体亚基对Cu（II）离子的结合导致荧光单元发射的淬灭。在9：1的DMSO-水溶液中，涂覆的二氧化硅纳米颗粒（CSN）选择性地检测低至纳摩尔浓度的铜离子。传感器的操作范围可以通过切换配体单元或通过修改组分比率来调谐。通过使用不同的荧光染料，可以容易地制备具有所需物理化学性质的传感器。此外，传感器组件的网络的组织引起合作和集体效应：一方面，结合到颗粒表面的配体亚基合作形成多价结合位点，具有对Cu（II）离子的增加的亲和力;另一方面，单个金属离子的结合导致几个荧光基团的淬灭，产生显著的信号放大。
The self-organization of the proper subunits of a fluorescence chemosensor on the surface of silica nanoparticles allows the easy design and realization of new effective sensing systems. Commercially available silica particles (20 nm diameter) were functionalized with triethoxysilane derivatives of selective Cu(II) ligands and fluorescent dyes. Grafting of the sensor components to the particle surface ensures the spatial proximity between the sensor components and, as a consequence, binding of Cu(II) ions by the ligand subunits leads to quenching of the fluorescent units emission. In 9 : 1 DMSO–water solution, the coated silica nanoparticles (CSNs) selectively detect copper ions down to nanomolar concentrations. The operative range of the sensors can be tuned either by switching the ligand units or by modification of the components ratio. Sensors with the desired photophysical properties can be easily prepared by using different fluorescent dyes. Moreover, the organization of the network of sensor components gives rise to cooperative and collective effects: on one hand, the ligand subunits bound to the particle surfaces cooperate to form multivalent binding sites with an increased affinity for the Cu(II) ions; on the other hand, binding of a single metal ion leads to the quenching of several fluorescent groups producing a remarkable signal amplification.