Polyethyleneimine-templated Ag nanoclusters: a new fluorescent and colorimetric platform for sensitive and selective sensing halide ions and high disturbance-tolerant recognitions of iodide and bromide in coexistence with chloride under condition of high
Polyethyleneimine-templated Ag nanoclusters: a new fluorescent and colorimetric platform for sensitive and selective sensing halide ions and high disturbance-tolerant recognitions of iodide and bromide in coexistence with chloride under condition of high
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DOI：
10.1021/ac3024526
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发表时间：
2012-11
影响因子：
7.4
通讯作者：
Fei Qu;N. Li;H. Luo
中科院分区：
文献类型：
--
作者：
Fei Qu;N. Li;H. Luo
由超支化聚乙烯亚胺功能化的Ag纳米团簇已经被开发为用于卤素离子（例如，Cl（-）、Br（-）和I（-））。识别机理是基于卤素离子与银原子之间的独特反应。特别是，卤化物诱导的氧化蚀刻和聚集可以产生强烈的荧光猝灭的银纳米团簇。该传感体系对卤离子的选择性比大多数阴离子和阳离子都高，线性范围和检测限都很低：Cl（-）的线性范围为0.5-80 μM，Br（-）的线性范围为0.1-14 μM，I（-）的线性范围为0.05-6 μM;在信噪比为3时，Cl（-）、Br（-）和I（-）的检测限估计分别为200、65和40 nM。在较高的离子强度条件下，Br（-）和I（-）在与Cl（-）共存时能被选择性地识别，这对真实的样品中Br（-）和I（-）的检测具有显著的优势。此外，由于比色法具有简单、快速、可靠、成本低等优点，因此也是一种很有前途的方法。该传感系统已成功地应用于真实的水样中Cl（-）的检测。
Ag nanoclusters functioned by hyperbranched polyethyleneimine have been developed as a new fluorescent and colorimetric platform for sensitive and selective recognition of halide ions (e.g., Cl(-), Br(-), and I(-)). The recognition mechanism is based on the unique reactions between halide ions and the silver atoms. In particular, halide-induced oxidative etching and aggregation can produce a strong fluorescence quenching of Ag nanoclusters. This sensing system exhibits a remarkably high selectivity toward halide ions over most of anions and cations and shows good linear ranges and lower detection limits: the linear ranges are 0.5-80 μM for Cl(-), 0.1-14 μM for Br(-), and 0.05-6 μM for I(-), respectively; the limits of detection for Cl(-), Br(-), and I(-), at a signal-to-noise ratio of 3, are estimated to be 200, 65, and 40 nM, respectively. Specifically, Br(-) and I(-) could be recognized selectively in the coexistence with Cl(-) under the condition of higher ionic strength, which is a significant advantage in the detection of Br(-) and I(-) in real samples. In addition, the recognition of halide could be performed by the colorimetric method, which is also attractive and promising because of its simplicity, rapidity, reliability, and low cost. Furthermore, this sensing system has been applied successfully to the detection of Cl(-) in real water samples.