基于量子点的荧光分析试纸用于Cu2+的现场可视化检测

On-site and visual copper(Ⅱ) test paper based on fluorescence quantum dots

构建了一种基于CdTe量子点的荧光分析试纸,并用于Cu^2+的现场快速可视化检测。首先通过油性笔在滤纸上描画的方法制作疏水堰,然后将合成的水溶性Cd Te量子点(λem=640nm,红色荧光)固定在疏水堰内,得到高通量的Cu^2+分析试纸。当水样中无Cu^2+存在时,在紫外灯下滤纸为红色。当水样中有Cu^2+存在时,量子点的红色荧光被淬灭,水样中Cu^2+浓度越大,在紫外灯下滤纸的荧光越弱。直接通过肉眼观察即可实现水样中低至5μmol·L^-1 Cu^2+的快速灵敏可视化检测,可满足生活饮用水中Cu^2+的现场快速检测的要求;并且该方法不需要大型仪器,成本低廉,为水体中Cu^2+的检测提供了一种新的工具,并可望用于水中其它离子或小分子的检测。

Herein,an on-site and visual Cu^2+test paper that based on fluorescence quantum dots was developed.We painted circles on a piece of filter paper as hydrophobic weir by permanent pen.By immobilization of water-soluble CdTe quantum dots(QDs)on the filter paper,an on-site test paper has been innovated to visualize trace Cu2+in water based on fluorescence quenching of QDs by Cu^2+.When Cu^2+was absent in the water sample,the test paper emitted red fluorescence under UV-light.While Cu^2+was present in the water sample,the test paper did not emit fluorescence under UV-light because of the quenching of QDs by Cu^2+.So Cu^2+could be on-site detected quickly just through naked eyes with a high sensitivity(the detection limit was as low as 5μmol·L^-1)and high selectivity.This test paper showed the capability of quantification Cu^2+in domestic water samples,with the advantage of low cost in usage and avoided the use of large-scale instrument.Therefore our developed test paper provides a new tool for Cu^2+detection and has great potential for micromolecule/ion detection in water samples.