化学学报 ›› 2014, Vol. 72 ›› Issue (5): 563-568.DOI: 10.6023/A14030201 上一篇    下一篇

研究论文

基于硅量子点电子转移荧光淬灭的2,4,6-三硝基甲苯/2,4,6-三硝基苯酚检测新方法

李西平, 刘斯佳, 吴战, 蒋健晖   

  1. 湖南大学化学化工学院化学生物传感与计量学国家重点实验室 长沙 410082
  • 收稿日期:2014-03-20 出版日期:2014-05-14 发布日期:2014-04-25
  • 通讯作者: 蒋健晖 E-mail:jianhuijiang@hnu.edu.cn
  • 基金资助:

    项目受国家自然科学基金(Nos. 21025521,21221003)和中央高校基本科研业务费(No. 531107040687)资助.

A Novel Approach to Detect 2,4,6-trinitrotoluene/2,4,6-trinitrophenol Based on Fluorescence Quenching via Charge Transfer of Silicon Quantum Dots

Li Xiping, Liu Sijia, Wu Zhan, Jiang Jianhui   

  1. State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082
  • Received:2014-03-20 Online:2014-05-14 Published:2014-04-25
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 21025521, 21221003) and the Fundamental Research Funds for the Central University (No. 531107040687).

提出了一种基于硅量子点电子转移荧光淬灭检测2,4,6-三硝基甲苯/2,4,6-三硝基苯酚的新方法. 在这个工作中,我们制备了一种表面氨基包覆的强荧光、抗光漂白、单分散的硅量子点. TNT/TNP与硅量子点表面的氨基通过化学识别形成稳定的Meisenheimer复合物,从而淬灭硅量子点的荧光并诱导其团聚. 硅量子点的荧光强度与TNT/TNP浓度的对数呈线性负相关,TNT和TNP的检测下限分别为50和5 pg/mL. 实验证明,该分析方法有较好的选择性并对分析介质的pH值不敏感,有望实现环境中TNT/TNP的实时、现场和超痕量检测.

关键词: 硅量子点, 电子转移, 荧光淬灭, 爆炸物分子

Due to the significant detrimental effects of nitroaromatic explosive on the environment and human health, sensitive, rapid, on-site and simple detection methods for explosives are in high demand. A novel label-free silicon quantum dots (SiQDs)-based sensor is designed for ultrasensitive detection of 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (TNP). In this work, amino-functionalized SiQDs are obtained through treating the SiQDs with (3-aminopropyl)triethoxysilane (APTES). The amine-coated SiQDs are not only water-stable but also highly luminescent. Based on the dramatic and selective fluorescence quenching of the amine-coated SiQDs due to charge transfer that resulting from the formation of stable Meisenheimer complexes between electron-deficient TNT/TNP and electron-rich primary amine on the surface of SiQDs, an instant and sensitive sensor is developed for the detection of TNT/TNP which is able to not only directly suppress the fluorescent emission intensity of SiQDs but also induce SiQDs aggregation to result in self-quenching of SiQDs. The results reveal that the developed sensor has high sensitivity for the detection of TNT/TNP. As indicated in experimental results, the fluorescence intensity is proportional to the concentration of TNT/TNP. Meanwhile, linear correlations are obtained respectively for the fluorescence signals to the logarithmic TNT and TNP concentration with 6 and 7 order of range and the detection limit of TNT and TNP is 50 pg/mL for TNT and 5 pg/mL for TNP. Further experiments demonstrate that this analytical method is not susceptible to pH and prevent interference from other nitroaromatics or cationic ions. This simple and cost-effective sensor can be used to detect ultra-trace TNT/TNP in groundwater or seawater. Additionally, this sensor strategy may provide a convenient, rapid, highly sensitive and selective assay platform for nitroaromatic explosive.

Key words: silicon quantum dots (SiQDs), charge transfer, fluorescence quenching, explosives