CdTe量子点作为荧光探针测定水环境中微量镉离子  

CdTe Quantum Dots as Fluorescent Probes for Determination of Trace Cadmium Ions in Water Environment

作　　者：高雪[1] 葛丹[1] 赵月[1] 张德福[1] 汤轶伟[1] 刘秀英[1] 励建荣[1] 

机构地区：[1]渤海大学化学化工与食品安全学院辽宁省食品安全重点实验室生鲜农产品贮藏加工及安全控制技术国家地方联合工程研究中心,锦州121013

出　　处：《化学通报》2015年第10期902-906,共5页Chemistry

基　　金：辽宁省食品安全重点实验室暨辽宁省高校重大科技平台开放课题(LNSAKF2013012)资助

摘　　要：利用CdTe量子点（QDs）和乙二胺四乙酸（EDTA）构建的纳米探针,建立了一种能快速灵敏检测Cd^2＋的新方法。利用EDTA溶液与Cd^2＋的络合作用对QDs的表面进行化学蚀刻,在QDs表面形成了Cd2＋的空腔,这些表面缺陷使得QDs荧光猝灭,而继续加入Cd^2＋后,新加入的Cd^2＋能够迅速补位空腔修复表面缺陷,使得QDs的荧光恢复。在最佳的实验条件下,当Cd2＋浓度在3.3×10^-9~6.7×10^-6mol/L范围时,QDs恢复的荧光强度与Cd^2＋浓度之间呈良好的线性关系,检出限为1.0×10^-9mol/L（S/N=3）。此外,相对于其他金属离子,该荧光探针对Cd^2＋具有高选择性,并且将其用于实际水样中Cd^2＋含量的检测,结果令人满意。In this study,an optical nanoprobe for Cd2 ＋detection has been constructed successfully based on CdTe quantum dots and ethylenediamine tetraacetic acid（ EDTA）. After chemical etching with EDTA,cavities of Cd^2 ＋on the surface of Cd Te QDs were generated and the fluorescence was quenched caused by the surface defects.Continuing to add Cd^2 ＋,specific Cd2 ＋recognition sites were created on the surface of the QDs,which could selectively bind Cd2 ＋,thereby repairing the surface defects and restoring the fluorescence of the QDs. Under optimal conditions,the change of the fluorescence intensity of quantum dots was in good linear relationship with the Cd2 ＋concentration in the range of 3. 3 × 10^- 9to 6. 7 × 10^- 6mol / L,and the detection limit was 1. 0 × 10^- 9mol / L（ S / N =3）. Furthermore,the present probe exhibited a high selectivity for Cd2 ＋over other metal ions and was successfully used in the detection of Cd2 ＋in real water samples.

关 键 词：量子点 化学蚀刻 荧光恢复 金属离子 

分 类 号：X832[环境科学与工程—环境工程] O657.3[理学—分析化学]