DNA based gold nanoparticles colorimetric sensors for sensitive and selective detection of Ag(I) ions
DNA based gold nanoparticles colorimetric sensors for sensitive and selective detection of Ag(I) ions
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基于 DNA 的金纳米颗粒比色传感器，用于灵敏、选择性地检测 Ag(I) 离子
DOI：
10.1016/j.aca.2009.04.022
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发表时间：
2009-06-30
影响因子：
6.2
通讯作者：
Dong, Shaojun
中科院分区：
文献类型：
--
作者：
Li, Bingling;Du, Yan;Dong, Shaojun
在这项工作中，我们报告了未标记和标记的传感策略，用于Ag（I）离子检测使用DNA为基础的金纳米粒子（AuNPs）比色法。在未标记策略中，富含C-碱基的单链DNA（C-ssDNA）缠绕到AuNPs上形成AuNPs/C-ssDNA复合物。在标记方法中，巯基修饰的C-ssDNA（HS-C-ssDNA）被共价标记在AuNPs上，以产生AuNPs-S-C-ssDNA复合物。在这两种策略中，C-ss DNA或HS-C-ssDNA可以增强AuNPs对盐诱导的聚集的稳定性。然而，在所获得的AuNPs/C-ssDNA或AuNPs-S-C-ssDNA复合物中Ag（I）离子的存在会降低这种稳定性，从而由于Ag（I）离子介导的C-Ag（I）-C碱基对的形成而显示紫色甚至蓝色。通过这种现象，Ag（I）离子可以定性和定量检测使用未标记和标记的传感策略。与标记方法相比，无标记策略避免了一般传感器的标记和分离步骤，从而节省了检测时间和成本。然而，标记策略提供了更敏感，稳定和可控的传感结果相比，未标记的方法。通过该标记策略，可以直接用肉眼观察到12 nM的Ag（I）离子，并且通过紫外-可见光谱测量得到最低可检测浓度为0.59 nM，这是基于DNA的AuNPs比色传感器中对金属离子最灵敏的结果之一。(C)2009爱思唯尔有限公司版权所有。
In this work, we reported both unlabeled and labeled sensing strategies for Ag(I) ions detection by using the DNA based gold nanoparticles (AuNPs) colorimetric method. In the unlabeled strategy, C-base riched single strand DNA (C-ssDNA) enwinded onto AuNPs to form AuNPs/C-ssDNA complex. In the labeled method, sulfhydryl group modified C-ssDNA (HS-C-ssDNA) was covalently labeled on AuNPs to produce AuNPs-S-C-ssDNA complex. In both strategies, C-ss DNA or HS-C-ssDNA could enhance the AuNPs stability against the salt-induced aggregation. However, the presence of Ag(I) ions in the obtained AuNPs/C-ssDNA or AuNPs-S-C-ssDNA complex would decrease such stability to display purple even blue colors due to the formation of Ag(I) ions mediated C-Ag(I)-C base pairs. Through this phenomenon, Ag(I) ions could be detected qualitatively and quantitatively using both unlabeled and labeled sensing strategies. Compared with the labeled method, the unlabeled strategy avoided the label and separation steps in common sensors, which may thus save both the time and cost for the detection. Nevertheless, the labeled strategy provided more sensitive, stable and controllable sensing results compared with the unlabeled method. By the labeled strategy, 12 nM Ag(I) ions could be observed directly by naked eyes, and the lowest detectable concentration of 0.59 nM was gotten under by the UV-vis spectra measurement, which was one of the most sensitive results among DNA based AuNPs colorimetric sensors for metal ions. (C) 2009 Elsevier B.V. All rights reserved.