基于EDTA蚀刻的CdTe/CdS量子点荧光探针检测水环境中痕量镉离子  

EDTA-Etched CdTe/CdS Quantum Dots Fluorescence Probe for Detection of Trace Cadmium Ions in Water Environment

作　　者：王心怡[1] 甘颖[1] 孙嘉弟 梁韬[1] 屠佳伟 周书祺 孔留兵 万浩[1] 王平[1] WANG Xinyi;GAN ying;SUN Jiadi;LIANG Tao;TU Jiawei;ZHOU Shuqi;KONG Liubing;WAN Hao;WANG Ping(Biosensor National Special Laboratory,Key Laboratory for Biomedical Engineering of Education Ministry,Department of Biomedical Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]浙江大学生物传感器国家专业实验室生物医学工程教育部重点实验室生仪学院

出　　处：《传感技术学报》2019年第8期1136-1143,共8页Chinese Journal of Sensors and Actuators

基　　金：国家重点基础研究发展计划(973计划)项目(2015CB352100)

摘　　要：设计了一种基于乙二胺四乙酸(EDTA)蚀刻的“关-开”模式的CdTe/CdS核壳量子点(QDs)的荧光传感器,具有高灵敏,高选择性,快速检测水环境中痕量Cd^2+的优点。EDTA通过在CdTe/CdS QDs表面进行化学蚀刻,使CdTe/CdS QDs表面的Cd 2+流失而和EDTA络合,在QDs表面形成空穴,得到特定的Cd^2+识别位点,从而导致荧光猝灭。Cd^2+的引入可以选择性的识别这些位点,使得EDTA-QDs体系的荧光恢复。在优化的工作条件下,该荧光传感器的线性响应范围为10μg/L^300μg/L和300μg/L^1 000μg/L,实现了Cd^2+在较大范围的测定要求,线性相关系数分别为0.997、0.985,检出限为0.22μg/L(0.002μmol/L)。达到了国家二类水质标准(GB/T 14848-93)对Cd^2+的检出限要求。此外,该荧光传感器对其他干扰离子的选择性优于1%,在实际水样检测中具有良好的实用性。A ethylenediaminetetraacetic acid(EDTA)-etched CdTe/CdS core-shell quantum dots(QDs)fluorescence sensor based on“off-on”mode was designed for highly sensitive,selective and rapid detection of trace Cd^2+in water environment.Chemical etching of QDs by EDTA produces surface voids that cause Cd^2+to bleed and complex with EDTA,resulting in fluorescence quenching.The added Cd 2+selectively recognizes these sites,recovering the fluorescence of EDTA-QDs system.Under the optimal conditions,the linear response range of this sensor is 10μg/L^300μg/L and 300μg/L^1 000μg/L,which realizes the wildly measurement of Cd^2+.The linear correlation coefficients are 0.997 and 0.985,respectively.And the detection limit was 0.22μg/L(0.002μmol/L),which has reached the detection limit of Cd^2+for the national second-class water quality standard(GB/T 14848-93).In addition,the fluorescence sensor has better selectivity to other interfering ions than 1%,and has good practicability in sample water.

关 键 词：荧光传感器 量子点 化学蚀刻 镉离子 

分 类 号：R318[医药卫生—生物医学工程]