基于ZnS∶Mn量子点荧光猝灭法测定磺胺嘧啶钠  

Fluorescent Quench Assay of Sulfadiazine Sodium Based on Mn-doped ZnS Quantum Dots

作　　者：占浔寿[1] 吴芳英[1] 

机构地区：[1]南昌大学化学系,江西南昌330031

出　　处：《分析测试学报》2011年第3期254-258,共5页Journal of Instrumental Analysis

基　　金：国家自然科学基金资助项目(20965006)

摘　　要：室温下，合成了巯基乙酸包裹的且在590nm处发射荧光的水溶性量子点ZnS：Mn。以该量子点为荧光探针，基于磺胺嘧啶钠（SDS）对量子点的荧光猝灭作用对其进行了定量检测。在pH7．4的KH2PO4-Na2HPO4（PBS）缓冲介质中，磺胺嘧啶钠溶液的浓度与量子点荧光强度变化呈线性关系，其线性范围为6．25×10^-63．75×10^-4mol·L^-1，相关系数r为0．998，检出限为3．86×10^～6mol·L^-1。该方法较常用检测方法简便、快捷，用于注射液样品分析，测定值与标示量一致，平均回收率为100％，结果满意。采用荧光光谱和紫外可见吸收光谱研究了ZnS：Mn量子点的发光性质及SDS对量子点荧光猝灭的可能机理，盐效应实验结果表明，量子点荧光的猝灭作用源于SDS通过静电作用诱导量子点表面的配体分子变化所致。Aqueous ZnS ： Mn quantum dots（ZnS ： Mn QDs） capped by thioglycolic acid and emit- ting fluorescence of 590 nm were obtained at room temperature. Based on the fluorescence quenching of ZnS ： Mn QDs caused by sulfadiazine sodium （SDS）, a simple, rapid and specific quantitative method was developed for the determination of SDS. Experimental conditions including temperature, reaction time and pH value of buffer affecting the detection for SDS were investigated. Under the optimal conditions, the calibration plot between the intensity ratio IF/＆0r/IF and the concentration of SDS was linear in the range of 6.25×10^-63.75×10^-4mol·L^-1 with a correlation coefficient of 0. 998. The limit of detection（LOD） （3σ/k） was 3.86 ×10^-6 mol · L^-1. The method was simple and rapid, and was applied in the determination of SDS in the injection sample with average recovery of 100%. In order to study the possible interaction mechanism, the influence of salt effect on the fluorescence intensity of QDs - SDS was discussed. The result indicated that SDS could bind to the ligand of ZnS ： Mn QDs surface through electrostatic force, which resulted in fluorescence quenching

关 键 词：锰掺杂硫化锌量子点 荧光猝灭 磺胺嘧啶钠 

分 类 号：O657.3[理学—分析化学] R978.2[理学—化学]