CdS/ZnS-CdTe量子点间荧光共振能量转移测定痕量汞  

Determination of trace mercury ions based on the fluorescence resonance energy transfer between CdS /ZnS Core-Shell quantum dots and CdTe quantum dots

作　　者：廖秀芬 陶慧林[1] 徐铭泽[1] 黎舒怀[1] 孙超[1] 钟福新[1] 易忠胜[1] 

机构地区：[1]桂林理工大学化学与生物工程学院,桂林541004

出　　处：《分析试验室》2014年第1期21-24,共4页Chinese Journal of Analysis Laboratory

基　　金：国家自然科学基金(61264007;21267008)项目资助

摘　　要：研究了CdS／ZnS核壳型量子点为能量给体，CdTe量子点为能量受体的荧光共振能量转移机理，及其在超痕量汞测定中的应用。实验表明在十二烷基苯磺酸钠存在下，于pH7．8的硼酸．硼酸钠缓冲液，CdS／ZnS与CdTe量子点之间能发生有效的能量转移。探讨了CdS／ZnS与CdTe量子点间能量转移机理。实验结果表明：Hg2＋的加入能使CdS／ZnS．cdTe体系发生荧光猝灭，且Hg“的浓度与体系荧光猝灭强度在一定范围内有良好的线性，据此建立了CdS／ZnS—CdTe—Hg2＋体系测定超痕量Hg2＋的方法。在优化条件下，Hg“的线性范围为2．0×10^-10～2．0×10^-8g／L，检出限为6．67×10^-11g/L（n=11）。方法应用于水样中Hg2＋的测定，其RSD≤4．1％（n=6），回收率为97．2％～99．8％。The fluorescence resonance energy transfer system between CdS/ZnS core-shell quantum dots （donor） and CdTe quantum dots （acceptor） has been constructed, and the optimal conditions were studied. Based on CdS/ZnS-CdTe fluorescence resonance energy transfer, we presented an ultra sensitive and highly selective plat- form for the detection of ultra trace Hg2＋ions. The results showed that in the alkaline sodium borate buffer with pH 7.8, CdS/ZnS core-shell quantum dots could transfer energy to CdTe quantum dots efficiently, which led to tile increase of CdTe fluorescence intensity markedly. While upon the addition of the Hg： ~ ions, the fluorescence quenching occurred when Hg2＋ interacted with CdTe. To a certain extent, there was a linear relationship be- tween the quenched level and Hg2＋ concentration. Hg2＋could be determined in the concentration range of 2.0 × 10^-10g/L to 2.0 × 10^-8 g/L. The detection limit was 6.6 × 10^-11 g/L （S/N = 3）. The method has been suc- cessfully applied to the determination of Hg2＋ ions in sewage water samples

关 键 词：CDS ZnS核壳型量子点 CDTE量子点 荧光共振能量转移 汞 

分 类 号：O657.3[理学—分析化学]