基于碳点的荧光纳米开关灵敏检测Cu(Ⅱ)离子和焦磷酸盐  

Luminescent Nanoswitch Based on Carbon Dots for Sensitive Detection of Cu(Ⅱ) Ions and Pyrophosphates

作　　者：周思慧 李琼 张婷 庞代文[1] 唐宏武[1] ZHOU Sihui;LI Qiong;ZHANG Ting;PANG Daiwen;TANG Hongwu(Key Laboratory of Analytical Chemistry for Biology and Medicine,Ministry of Education,College of Chemistry and Molecular Sciences,Wuhan University,Wuhan 430072,China)

机构地区：[1]生物医学分析化学教育部重点实验室武汉大学化学与分子科学学院

出　　处：《高等学校化学学报》2019年第8期1593-1599,共7页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:81572086,81772256,21827808)资助~~

摘　　要：利用羟基与氨基在高温条件下反应,不断聚合生成碳点(CDs),该碳点可发射不依赖激发波长的明亮的红色荧光.将CDs作为目标敏感荧光团时,发现Cu^2+可特异性猝灭碳点的荧光,而焦磷酸盐(PPi)可在一定程度上恢复上述体系的荧光.其中,Cu^2+对CDs的荧光猝灭是由于Cu^2+与CDs发生络合反应,从而发生静态猝灭过程;而加入PPi之后,由于它与CDs的结合能力更强,因此Cu^2+离开CDs的表面,体系的荧光得以恢复.在此基础上构建了一种高选择性、高灵敏度的off-on荧光纳米开关传感体系,分别用于Cu^2+和PPi的定量检测,检出限分别达2.14μmol/L和1.85μmol/L.该传感体系可应用于实际样品检测,拓宽了荧光CDs的传感应用,为其在生物体内目标分子的检测提供了可能性.Carbon dots(CDs) with brightly red fluorescence were prepared via a facile one-step synthesis way by hydroxyl and amino groups to react at high temperature. The as-obtained CDs can overcome the excitation-dependence luminescence behavior for normal routes and the quantum yield is up to 41%. Based on the fluorescent materials, a luminescent nanoswitch through fluorescence on and off in response to specific external stimuli was designed. Fluorescence quenching of CDs by Cu^ 2+ is ascribed to the complexation reaction. When pyrophosphate(PPi) is introduced into the system, Cu^ 2+ leaves CDs’ surface because PPi binds to CDs much stronger than Cu^ 2+ , resulting in the fluorescence recovery. Following the proposed way, a signal off-on nanoswich sensing system for the detection of Cu^ 2+ and PPi with high selectivity and sensitivity was constructed, and the detection limits for Cu^ 2+ and PPi are 2.14 μmol/L and 1.85 μmol/L, respectively. This method has been applied in real samples, and this strategy broadens the sensing application of fluorescent CDs, providing the possibility to determine these targets in living systems.

关 键 词：碳点 荧光传感 Cu^ 2+ 检测 焦磷酸盐 

分 类 号：O657.3[理学—分析化学]