Nanosensors Based on Viologen Functionalized Silver Nanoparticles: Few Molecules Surface. Enhanced Raman Spectroscopy Detection of Polycyclic Aromatic Hydrocarbons in Interparticle Hot Spots
Nanosensors Based on Viologen Functionalized Silver Nanoparticles: Few Molecules Surface. Enhanced Raman Spectroscopy Detection of Polycyclic Aromatic Hydrocarbons in Interparticle Hot Spots
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DOI：
10.1021/ac8021746
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发表时间：
2009-02-15
影响因子：
7.4
通讯作者：
Sanchez-Cortes, Santiago
中科院分区：
文献类型：
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作者：
Guerrini, Luca;Garcia-Ramos, Jose V.;Sanchez-Cortes, Santiago
本文报道了紫精配离子（VGD）对银纳米粒子（Ag NPs）的功能化及其在多环芳烃（PAHs）表面增强拉曼散射（Sers）检测中的应用。VGD能够在分析物可以被分配的颗粒间结（Sers热点）处形成分子间空腔。Ibis导致目标分子的拉曼发射的巨大增强。这种效应被应用于多环芳烃的检测，多环芳烃是存在于大气和沃茨中最广泛和最危险的污染物之一。基于不同的VGD（光泽精，敌草快，百草枯）的传感系统之间的比较进行检测的两种多环芳烃（芘和苯并[c]菲）。用光泽精（LG）的官能化提供了最强大和稳定的VGD-NPs传感器，其允许在宏观设置中低至10（-9）M的芘（PYR）的Sers检测，并且对于通过单个NPs聚集体获得的光谱（微观设置）在zeptomole范围内。此外，Sers光谱还提供了VGD与多环芳烃相互作用机理的重要结构信息，揭示了VGD与PYR之间形成CT复合物以及主体构象的变化。的位置的v（Ag-Cl）带和等离子体共振分配给银二聚体的贡献也被用作光谱标记，以监测主机-客体相互作用。
The functionalization of silver nanoparticles (Ag NPs) by viologen dications (VGDs) is reported in this work as well as their applications in the surface-enhanced Raman scattering (SERS) detection of polycyclic aromatic hydrocarbons (PAHs). VGDs are able to form intermolecular cavities at interparticle junctions (SERS hot spots) where the analyte can be allocated. Ibis leads to a giant intensification of the Raman emission of the target molecule. This effect was applied in the detection of PAHs, one of the most widespread and dangerous group of pollutants existing in the atmosphere and waters. A comparison between sensing-systems based on different VGDs (lucigenin, diquat, and paraquat) was done for the detection of two PAHs (pyrene and benzo[c]phenanthrene). The functionalization with lucigenin (LG) provided the most powerful and stable VGD-NPs sensor, which allowed the SERS detection of pyrene (PYR) down to 10(-9) M in the macro setup and in the zeptomole range for spectra obtained by single NPs aggregates (micro setup). Besides, SERS spectra afforded important structural information about the interaction mechanism of VGD and PAHs, revealing the formation of a CT complex between the VGD and PYR and changes in the host conformation. The position of the v(Ag-Cl) band and the plasmon resonance contribution assigned to Ag dimers were also used as spectral markers to monitor the host-guest interaction.