摘要
以蔗糖为碳源、尿素为氮源,通过一步水热法制得荧光性能好、水溶性强的氮掺杂碳量子点(N-CQDs)。N-CQDs在λex=285 nm波长激发下,于波长376 nm处有强荧光发射峰,Hg^(2+)能够使N-CQDs于376 nm处的荧光发射峰发生明显的猝灭;于上述猝灭体系中再引入Cl^(-),Cl^(-)能够使N-CQDs-Hg^(2+)猝灭体系的荧光强度再次回升,荧光信号重新开启。基于Hg^(2+)对体系荧光强度的猝灭及Cl^(-)对猝灭体系荧光信号的恢复作用,可构建直接高灵敏测定Hg^(2+)和Cl^(-)的新型荧光传感探针。探讨了Hg^(2+)对N-CQDs的荧光猝灭机理和Cl^(-)对N-CQDs-Hg^(2+)体系荧光信号的恢复机理。在优化条件下,Hg^(2+)和Cl^(-)分别在浓度0.7~80μmol/L和10~100μmol/L范围内与N-CQDs荧光信号猝灭值及荧光信号恢复值有良好的线性关系。Hg^(2+)检出限为0.26μmol/L,Cl^(-)检出限为4.3μmol/L。该荧光探针可用于环境水样中Hg^(2+)和Cl^(-)浓度的高灵敏测定。
Water-soluble N-doped carbon quantum dots(N-CQDs)were prepared through one-step hydrothermal method by using sucrose as carbon source,and urea as nitrogen source.The synthesized N-CQDs showed a strong fluorescence emission peak at 376 nm when excited atλ_(ex)=285 nm.It was found that Hg^(2+)can significantly quench the signal at 376 nm.However,the quenched signal at 376 nm gradually recovered in the presence of Cl^(-).Therefore,an ultra-sensitive fluorescence sensing probe for Hg^(2+)and Cl determination was constructed.Under the optimum conditions,the fluorescence intensity at 376 nm showed good linear relationships with the concentrations of Hg^(2+)and Cl^(-)in the range of 0.7-80μmol/L and 10-100μmol/L,respectively.The detection limits of Hg^(2+)and Cl^(-)were 0.26μmol/L and 4.3μmol/L,respectively.The detailed reaction mechanism was discussed.This fluorescence probe was further applied to analyze Hg^(2+)and Cl^(-)in environmental water samples with satisfactory results.
作者
张诗雨
张越诚
马静
雷金川
孙凌波
马红燕
ZHANC Shiyu;ZHANC Yuecheng;MA Jing;LEI Jinchuan;SUN Lingbo;MA Hongyan(College of Chemistry and Chemical Engineering,Yan'an Key Laboratory of Analytical Technology and Detection,Yan'an 716000,China;Medical College,Yan'an University,Yan'an 716000,China)
出处
《分析试验室》
EI
CAS
CSCD
北大核心
2024年第8期1102-1108,共7页
Chinese Journal of Analysis Laboratory
基金
国家自然科学基金(22264023)
陕西省教育厅科研计划(22JK0614)
延安大学博士科研启动基金(YDBK2022-15,YDBK2020-30)
陕西省卫健委科研基金(2022E019)项目资助。
作者简介
张诗雨,女(1998-),硕士研究生。研究方向:发光分析,3107758739@qq.com;通信作者:孙凌波,女(1990-),博士,讲师。研究方向:生化分析,lingbosun@yau.edu.cn;通信作者:马红燕,女(1966-),硕士,教授。研究方向:发光分析,Mahy6614@163.com。
