ZnSe量子点作为荧光探针测定微量Ag^+  

Determination of Trace Silver Based on ZnSe Quantum Dot Fluorescent Probes

作　　者：刘冰洁[1] 王瑞[1] 舒娟[1] 单晓辉 廖声华[1] 严拯宇[1] 

机构地区：[1]中国药科大学理学院分析化学教研室,江苏南京211198 [2]莱州出入境检验检疫局,山东烟台261411

出　　处：《分析科学学报》2014年第3期309-313,共5页Journal of Analytical Science

基　　金：国家自然科学基金(No.81173023);大学生创新药物研制能力提高项目(No.J1030830);国家级大学生创新创业训练计划(No.G13003);江苏省2013年度普通高校研究生科研创新计划(No.CXLX13-312)

摘　　要：以谷胱甘肽为稳定剂,在水相中合成了ZnSe量子点(QDs)。基于Ag+对ZnSe QDs的荧光猝灭作用,建立了以QDs作为荧光探针测定微量Ag+的新方法。结果表明:在优化条件下,Ag+的浓度在7.85~157.01μg·L-1范围内和F0/F有良好的线性关系,相关系数r为0.9989,检测限为0.12μg·L-1。由Stern-Volmer方程获得了反应的猝灭常数和双分子猝灭速率常数,由双倒数方程获得了Ag+与ZnSe QDs相互作用的结合常数、结合位点数,并判断出其作用机理为静态猝灭。根据热力学方程计算热力学参数,结果表明Ag+与ZnSe QDs的相互作用为自发过程,主要为静电作用力。ZnSe quantum dots were synthesized with GSH as a stabilizer in aqueous solution. Based on the quenching effect of Ag＋ on the fluorescence of ZnSe QDs,a method for determination of trace silver was developed. The results showed that under the optimized conditions, there was a good linear relationship between Fo/F and Ag＋ concentration in range of 7.85-157.01 μg-L-1, with correlation coefficient of 0. 9989 and detection limit of 0.12 μg·L-1. Quenching constant and bimolecular quenching rate constant were obtained according to Stern Volmer equation, the binding constant and binding site number of interaction were also calculated according to Lineweaver-Burk equation. It is demonstrated that the quenching mechanism is static quenching. According to thermodynamic equation, the thermodynamic parameters were calculated. The results indicated that the interaction between ZnSe QDs and Ag＋ was spontaneous and induced mainly by electrostatic force.

关 键 词：ZNSE QDS Ag+ 荧光猝灭 热力学参数 

分 类 号：O657.39[理学—分析化学]