Jia Lei, Guo Shengli, Xu Jun, Chen Xiangzhen, Zhu Tinghui, Zhao Tongqian
College of Chemistry and Chemical Engineering, Henan Polytechnic University, Jiaozuo 454000, China.
Institute of Resources & Environment, Henan Polytechnic University, Jiaozuo 454000, China.
Nanomaterials (Basel). 2019 Jul 4;9(7):976. doi: 10.3390/nano9070976.
Tetracycline (TC) residues are harmful to the environment and human body, so it is necessary to develop a highly sensitive probe for rapid detection of tetracycline residues. In the present paper, a novel dye-doped porous metal-organic framework (UiO-66)-based multi-color fluorescent nano-probe was designed for sensitive ratiometric detection of tetracycline (TC). In this probe, dye-molecules doped UiO-66 was used as a fluorescent internal standard, and the externally grafted lanthanide Eu complex was used as response signals. The fluorescence of the Eu complex was selectively enhanced with increasing concentrations of TC, which was accompanied by a visual blue-to-red color switch. The nano-probe had a linear response between 0.1 and 6 μM with a lowest detection limit of 17.9 nM, which was much lower than the maximum residue limits set by the United States Food and Drug Administration (676 nM) and the European Union (225 nM). The applicability of this method in the analysis of actual samples was evaluated by the determination of TC in honey and milk samples, indicating satisfactory recovery and good reproducibility. In addition, a cost-effective paper-based probe for rapid and visual detection of TC was developed by fixing the nano-probe on filter papers. With the help of a smartphone camera to capture the fluorescence color, and chromaticity analysis software, the calculation and analysis of red (R) and blue (B) values can be realized, which has the potential for real-time visual detection of TC.
四环素（TC）残留对环境和人体有害，因此有必要开发一种用于快速检测四环素残留的高灵敏度探针。本文设计了一种基于新型染料掺杂多孔金属有机框架（UiO-66）的多色荧光纳米探针，用于灵敏的四环素（TC）比率检测。在该探针中，染料分子掺杂的UiO-66用作荧光内标，外部接枝的镧系元素铕配合物用作响应信号。随着TC浓度的增加，铕配合物的荧光选择性增强，同时伴随着明显的从蓝色到红色的颜色转变。该纳米探针对0.1至6 μM的TC具有线性响应，最低检测限为17.9 nM，远低于美国食品药品监督管理局（676 nM）和欧盟（225 nM）设定的最大残留限量。通过测定蜂蜜和牛奶样品中的TC来评估该方法在实际样品分析中的适用性，结果表明回收率令人满意且重现性良好。此外，通过将纳米探针固定在滤纸上，开发了一种用于快速可视化检测TC的经济高效的纸质探针。借助智能手机摄像头捕获荧光颜色，并利用色度分析软件，可以实现红色（R）和蓝色（B）值的计算和分析，具有对TC进行实时可视化检测的潜力。
