中文摘要：

本文以柠檬酸（Citric Acid,CA）为碳源,聚乙烯亚胺（Branched Polyethylenimine,BPEI）为钝化剂,采用水热法合成了高荧光量子产率的碳点（Carbon Dots,CDs）。使用紫外-可见光谱、红外光谱、荧光光谱及原子力显微镜等对制得的CDs进行表征。制备的CDs粒径分布均匀,主要在3-6nm之间,量子产率为39.8%。由于CDs的发射光谱和硫黄素T（Thioflavin T,ThT）的激发光谱有很大程度的重叠,基于荧光内滤效应构建了测定Cu（Ⅱ）的BPEI-CDs/ThT体系,该体系测定Cu（Ⅱ）有很高的灵敏度和选择性,线性范围为5.0×10^-8-5.0×10^-5 mol/L,检测限为1.0×10^-8 mol/L。

英文摘要：

In this paper,BPEI-carbon dots（CDs）were prepared by hydrothermal synthesis method with citric acid as the carbon source and branched polyethyleneimine（BPEI）as the passivating agent.The prepared BPEI-CDs were characterized by UV-Vis spectroscopy,infrared spectroscopy,fluorescence spectroscopy and atomic force microscopy.The carbon dots showed a uniform particle size distribution,mostly among 3-6nm,and strong fluorescence yield of 39.8%.Emission spectrum of carbon dots can perfectly overlap with the absorption spectrum of Thioflavin T.ABPEI-CDs/ThT system based on fluorescence inner filter effect for the detection of Cu（Ⅱ）ion with good sensitivity and selectivity was constructed.Under the optimum conditions,the response was linearly proportional to the concentration of Cu（Ⅱ）ion in the range of 5.0×10^-8-5.0×10^-5 mol/L with the detection limit of 1.0×10^-8 mol/L.