巯基琥珀酸修饰的CdTe量子点荧光猝灭法测定果蔬中的微量铜  

Determination of Trace Copper in Fruits and Vegetables by CdTe Quantum Dots Fluorescence Quenching

作　　者：董焱[1] 王莹[2] 徐淑坤[3] 董微[4] 

机构地区：[1]沈阳药科大学中药学院实验中心,沈阳市110016 [2]辽宁大学生命科学院,沈阳市110036 [3]东北大学化学系,沈阳市110819 [4]沈阳医学院化学教研室,沈阳市黄河北大街146号110034

出　　处：《光谱实验室》2012年第6期3813-3816,共4页Chinese Journal of Spectroscopy Laboratory

基　　金：国家自然基金资助项目(20875011);辽宁省自然基金资助项目(20102221);辽宁省教育厅资助项目(L2010542);辽宁省教育厅杰出青年学者成长计划(LJQ2011109);沈阳市科技局资助项目(F11-262-9-21)

摘　　要：以巯基琥珀酸(MSA)为稳定剂,在水溶液中制备稳定的CdTe量子点。基于Cu2+在磷酸盐缓冲液中对该量子点的荧光具有较强的猝灭作用,建立一种简便灵敏的测定铜的新方法。考察了量子点的浓度,缓冲液pH、和反应时间等对Cu2+测定的影响。结果表明,CdTe量子点浓度为0.0306mmol/L,在0.2mmol/L的磷酸盐缓冲液(pH7.4)中,反应时间为5min,体系的相对荧光强度与Cu2+浓度呈良好的线性关系,其线性范围为1.28—38.4μg/L,检出限为0.023μg/L(3σ)。方法操作简便,快速,可用于果蔬中Cu2+含量的测定。Stable CdTe quantum dots （QDs） were synthesized with mercaptosuccinic acid （MSA） as stabilizing agent in aqueous solution. Based on the strong quenching of fluorescence intensity of CdTe QDs by Cu2＋ in phosphate buffer,a simple,rapid and sensitive new method for the determination of copper was developed. The influences of the effects of experimental conditions, including concentration of CdTe QDs,pH of buffer and reacting time on determination of Cuz＋ were investigated. The results showed that when the concentration of QDs was 0. 0306mmol/L in 0. 2mmol/L phosphate buffer at pH 7.4 and the reaction time was 5min, the relative fluorescence intensity of CdTe QDs was linear with Cu2＋ concentration in the range of 1.28--38.4μg/L ,the limit of detection （38） was 0. 023μg/L. This method is simple and fast,and can be used for determination of Cu2＋ in fruits and vegetables.

关 键 词：巯基琥珀酸修饰的CdTe量子点 荧光猝灭 铜 

分 类 号：O657.32[理学—分析化学]