The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China.
The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2018 Aug 5;201:119-127. doi: 10.1016/j.saa.2018.04.065. Epub 2018 May 1.
Cadmium-caused environmental pollution and diseases have always been worldwide problems. Thus it is extremely urgent to establish a cheap, rapid, simple and selective detection method for trace cadmium in drinking water. In this study, a fluorescence "turn-on" method based on ethylene diamine tetraacetic acid (EDTA)-etched CdTe@CdS quantum dots (QDs) was designed to detect Cd. High resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) were utilized for chemical and structural characterization of the as-prepared QDs. Based on chemical etching of EDTA on the surface of CdTe@CdS QDs, specific Cd recognition sites were produced, and then results in fluorescence quenching. The introduction of Cd could identify these sites and restore the fluorescence of the EDTA-QDs system. Under the optimum conditions, the nanoprobe shows a linear response range from 0.05 to 9 μM with a very low detection limit of 0.032 μM. In addition, the reported fluorescence probe in this work displays a good selectivity for trace Cd over other metal ions and an admirable practicability in real water samples.
镉引起的环境污染和疾病一直是全球性的问题。因此，建立一种廉价、快速、简单和选择性的检测饮用水中痕量镉的方法极为迫切。在本研究中，设计了一种基于乙二胺四乙酸（EDTA）刻蚀 CdTe@CdS 量子点（QD）的荧光“开启”方法来检测 Cd。高分辨率透射电子显微镜（HRTEM）和 X 射线光电子能谱（XPS）用于对所制备的 QD 进行化学和结构表征。基于 EDTA 在 CdTe@CdS QD 表面的化学刻蚀，产生了特定的 Cd 识别位点，然后导致荧光猝灭。引入 Cd 可以识别这些位点并恢复 EDTA-QD 体系的荧光。在最佳条件下，纳米探针在 0.05 至 9 μM 的线性响应范围内显示出非常低的检测限 0.032 μM。此外，本工作中报道的荧光探针对痕量 Cd 具有良好的选择性，对其他金属离子具有良好的选择性，在实际水样中具有良好的实用性。
