硒化锌量子点作探针荧光法检测农药敌磺钠  

Fluorescence Spectral Method for Determination of Fenaminosulf with ZnSe Quantum Dots as the Probe

作　　者：刘正清[1,2] 殷鹏飞[1,2] 龚会平[1,2] 王晓丹[1,2] 李萍萍[1,2] 何佑秋[1,2] 

机构地区：[1]发光与实时分析教育部重点实验室,重庆400715 [2]西南大学化学化工学院,重庆400715

出　　处：《西南大学学报（自然科学版）》2012年第3期71-75,共5页Journal of Southwest University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(20875078);发光与实时分析重庆市重点实验室(西南大学)资助项目(CSTC;2006CA8006)

摘　　要：以谷胱甘肽(GSH)为稳定剂,在水相中合成了高荧光的硒化锌量子点(ZnSe QDs).实验发现,农药敌磺钠能显著猝灭ZnSe QDs的荧光,同时采用荧光光谱和吸收光谱研究了敌磺钠与ZnSe QDs相互作用的荧光猝灭机理.通过对比3个温度下体系的Stern-Volmer方程动态猝灭常数KSV发现,敌磺钠对ZnSe QDs的荧光猝灭主要为动态过程.利用二者的猝灭作用建立了对农药敌磺钠的高灵敏检测新方法,其线性范围为6.69×10-7～2.23×10-4 mol/L,相关系数为R=0.999,检出限为2.01×10-7 mol/L.用该方法对自来水中残留农药进行检测,加标回收率在95.8%～105%之间.Glutathione （GSH） is employed as the stabilizing agent to synthesize highly fluorescent ZnSe quantum dots（QDs） in water phase. The interaction of as-prepared ZnSe QDs with the pesticide fenamin osulf demonstrates that ZnSe QDs fluorescence can be strongly quenched by fenaminosulf at room temperature. Additionally, the quenching mechanism of the ZnSe quantum dots by fenaminosulf is investigated by fluorescence spectrum and UV-absorption spectrum. The intensity Stern-Volmer plot for quenching by fenaminosulf shows a clear upward curvature with Ksv at three different temperatures. It is clear that the fluorescence intensity of ZnSe QDs is decreased mainly by collisional quenching with fenaminosulf. A high- ly sensitive fluorimetric method for the determination of fenaminosulf is established by using ZnSe QDs as a sensor. The calibration curve is linear over the concentration range of 6.69×10^-7-2.23×10^-1mol/L with a correlation coefficient of 0. 999 and a limit of detection of 2.01 ×10^-7 mol/L. The proposed method has been applied to the determination of fenaminosulf residues in the tap water with standard addition recoveries of 95.8%- 105%.

关 键 词：ZNSE量子点 荧光 紫外吸收 敌磺钠 

分 类 号：O657.3[理学—分析化学]