Li Jing, Zhang Caiyun, Yin Mingyuan, Zhang Zhen, Chen Yujie, Deng Qiliang, Wang Shuo
Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Key Laboratory of Food Nutrition and Safety, College of Chemical Engineering and Materials Science, Tianjin University of Science and Technology, Tianjin 300457, China.
Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University, Tianjin 300071, China.
ACS Omega. 2019 Sep 20;4(14):15947-15955. doi: 10.1021/acsomega.9b01996. eCollection 2019 Oct 1.
Perfluorooctane sulfonate (PFOS) known as a persistent organic pollutant has been attracting great interests due to its potential ecotoxicity. An approach capable of sensing ultra-trace PFOS is in urgent demand. Here, we developed an approach for highly sensitive sensing PFOS using surfactant-sensitized covalent organic frameworks (COFs)-functionalized upconversion nanoparticles (UCNPs) as a fluorescent probe. COFs-functionalized UCNPs (UCNPs@COFs) were obtained by solvothermal growth of 1,3,5-triformylbenzene and 1,4-phenylenediamine on the surface of UCNPs. COF's layer on the surface of UCNPs not only provides recognition sites for PFOS but also improves the fluorescence quantum yields from 2.15 to 5.12%. Trace PFOS can quench the fluorescence emission of UCNPs@COFs at 550 nm due to the high electronegativity of PFOS. Moreover, the fluorescence quenching response can be significantly strengthened in the presence of a surfactant, which causes more sensitivity. The fluorescence quenching degrees ( - ) of the system are linear with the concentration of PFOS in the range of 1.8 × 10 to 1.8 × 10 M. The present sensor can sensitively and selectively detect PFOS in tap water and food packing with the limit of detection down to 0.15 pM (signal-to-noise ratio = 3), which is comparable to that of the liquid chromatography-mass spectrometry technique. The proposed approach realized a simple, fast, sensitive, and selective sensing PFOS, showing potential applications in various fields.
全氟辛烷磺酸（PFOS）作为一种持久性有机污染物，因其潜在的生态毒性而备受关注。迫切需要一种能够检测超痕量PFOS的方法。在此，我们开发了一种高灵敏度检测PFOS的方法，该方法使用表面活性剂敏化的共价有机框架（COFs）功能化的上转换纳米颗粒（UCNPs）作为荧光探针。通过在UCNPs表面溶剂热生长1,3,5-三苯甲醛和1,4-苯二胺，获得了COFs功能化的UCNPs（UCNPs@COFs）。UCNPs表面的COF层不仅为PFOS提供了识别位点，还将荧光量子产率从2.15%提高到了5.12%。由于PFOS的高电负性，痕量PFOS可以猝灭UCNPs@COFs在550nm处的荧光发射。此外，在表面活性剂存在下，荧光猝灭响应可以显著增强，从而提高灵敏度。该系统的荧光猝灭程度（-）与PFOS浓度在1.8×10至1.8×10 M范围内呈线性关系。本传感器能够灵敏且选择性地检测自来水中和食品包装中的PFOS，检测限低至0.15 pM（信噪比=3），与液相色谱-质谱技术相当。所提出的方法实现了对PFOS的简单、快速、灵敏和选择性检测，在各个领域显示出潜在的应用价值。
