文献类型：期刊文献

英文题名：A quantum dot-based "off-on" fluorescent probe for biological detection of zinc ions

作者：Xu, Hu[1];Wang, Zhiping[1];Li, Yan[1];Ma, Shijian[1];Hu, Peiyi[1];Zhong, Xinhua[1]

机构：[1]E China Univ Sci & Technol, Dept Chem, Inst Appl Chem, Shanghai 200237, Peoples R China

年份：2013

卷号：138

期号：7

起止页码：2181

外文期刊名：ANALYST

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000315598500037)】；

基金：We thank the Natural Science Foundation of China (no. 21175043), the Fundamental Research Funds for the Central Universities, National Innovation Experiment Program for University Students (no. 111025119), Chenguang Program of the Shanghai Education Commission (no. 11CG31), the Fujian Provincial Key Laboratory of Nanomaterials (NM10-06), and the Program for Professor of Special Appointment at Shanghai Institutions of Higher Learning for financial support.

语种：英文

摘要：Since zinc ions play an important role in various physiological activities, developing a facile detection method for Zn2+ is highly desirable. Owing to their superior optical properties, semiconductor quantum dots (QDs) have been developed as a promising alternative for organic fluorophores in fluorescence analysis. In this study, water soluble di-2-picolylamine-dithiolcarbamate (DPA-DTC)/proline-dithiolcarbamate (P-DTC) co-capped CdSe/ZnS QDs as a sensitive and selective "turn-on" fluorescence probe for Zn2+ was reported. The probe was easily obtained via ligand exchange. The initial bright fluorescence of QDs was effectively quenched by DPA-DTC that acted as an effective hole trapper. Upon complexation with Zn2+, the formation of Zn2+-DPA-DTC complex altered the energetic position of the HOMO for DPA-DTC, which rendered it unfavorable for the hole transfer. Thus the QDs PL was switched on. Under optimal conditions, a good linear relationship between the fluorescence response and Zn2+ concentration could be obtained in the range from 0.9 to 16 mu M. The limit of detection for Zn2+ was found to be 0.7 mu M. Furthermore, the present probe exhibited a high selectivity for Zn2+ over other common metal ions and was successfully used in the detection of Zn2+ in simulated biological fluids.