Ag Nanocluster/DNA Hybrids: Functional Modules for the Detection of Nitroaromatic and RDX Explosives
Ag Nanocluster/DNA Hybrids: Functional Modules for the Detection of Nitroaromatic and RDX Explosives
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DOI：
10.1021/nl502720s
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发表时间：
2014-08-01
期刊：
影响因子：
10.8
通讯作者：
Willner, Itamar
中科院分区：
文献类型：
--
作者：
Enkin, Natalie;Sharon, Etery;Willner, Itamar
由核酸稳定的发光银纳米团簇（NC）被实现为用于检测爆炸物苦味酸、三硝基甲苯（TNT）和六氢-1，3，5-三硝基-1，3，5-三嗪（RDX）的光学标记。传感模块由两部分组成，具有核酸稳定的Ag NC的核酸和用供电子单元（包括L-DOPA、L-酪氨酸和6-羟基-L-DOPA）官能化的核酸，其在核酸支架上自组装。硝基取代的炸药，表现出电子，受体的性质，和电子给位点，与传感模块，集中在紧密接近的银NC炸药之间的供体-受体复合物的形成。这导致了电子转移猝灭的银纳米粒子的发光的爆炸分子。Ag NC的发光的淬灭为感测过程提供了读出信号。分析平台的灵敏度由给体取代基的供电子性质控制，并且发现6-羟基-L-多巴是最灵敏的给体。使用6-羟基-L-DOPA-修饰的Ag NCs传感模块分析苦味酸、TNT和RDX，检测限分别对应于5.2 × 10（-12）M、1.0 × 10（-12）M和3.0 × 10（-12）M。
Luminescent Ag nanoclusters (NCs) stabilized by nucleic acids are implemented as optical labels for the detection of the explosives picric acid, trinitrotoluene (TNT), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). The sensing modules consist of two parts, a nucleic acid with the nucleic acid-stabilized Ag NCs and a nucleic acid functionalized with electron-donating units, including L-DOPA, L-tyrosine and 6-hydroxy-L-DOPA, self-assembled on a nucleic acid scaffold. The formation of donor-acceptor complexes between the nitro-substituted explosives, exhibiting electron. acceptor properties, and the electron-donating sites, associated with the sensing modules, concentrates the explosives in close proximity to the Ag NCs. This leads to the electron-transfer quenching of the luminescence of the Ag NCs by the explosive molecule. The quenching of the luminescence of the Ag NCs provides a readout signal for the sensing process. The sensitivities of the analytical platforms are controlled by the electron-donating properties of the donor substituents, and 6-hydroxy-L-DOPA was found to be the most sensitive donor. Picric acid, TNT, and RDX are analyzed with detection limits corresponding to 5.2 X 10(-12) M, 1.0 x 10(-12) M, and 3.0 x 10(-12) M, respectively, using the 6-hydroxy-L-DOPA-modified Ag NCs sensing module.