文献类型：期刊文献

英文题名：Carbon dots as fluorescent probes for "off-on" detection of Cu2+ and L-cysteine in aqueous solution

作者：Zong, Jie[1,2,3];Yang, Xiaoling[1];Trinchi, Adrian[2];Hardin, Simon[2];Cole, Ivan[2];Zhu, Yihua[1];Li, Chunzhong[1];Muster, Tim[2];Wei, Gang[3]

机构：[1]E China Univ Sci & Technol, Sch Mat Sci & Engn, Minist Educ, Key Lab Ultrafine Mat, Shanghai 200237, Peoples R China;[2]CSIRO Mat Sci & Engn CMSE, Clayton, Vic 3168, Australia;[3]CSIRO Mat Sci & Engn CMSE, Lindfield, NSW 2070, Australia

年份：2014

卷号：51

起止页码：330

外文期刊名：BIOSENSORS & BIOELECTRONICS

收录：;EI(收录号：20133616710596);WOS:【SCI-EXPANDED(收录号:WOS:000326905500050)】；

基金：This work was supported by the National Natural Science Foundation of China (21236003, 21206042, 20925621, 20976054 and 21176083), the Fundamental Research Funds for the Central Universities, the Program for Changjiang Scholars and Innovative Research Team in University (IRT0825), the Shanghai Leading Academic Discipline Project (Project no.: B502), China Scholarship Council, and the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Australia Function Interfaces Research Group for the financial support.

语种：英文

外文关键词：Mesoporous silica; Carbon dots; Fluorescent probe; Copper ions; L-cysteine; "off-on" detection

摘要：Copper ion (Cu2+) and L-cysteine (L-Cys) detection is critically important since an abnormal level of Cu2+ or L-Cys is an indicator for many diseases. In this paper, we demonstrate an "off-on" approach for highly sensitive and selective detection of Cu2+ and L-Cys using carbon dots (CDs) as fluorescent probes. CDs were prepared by using mesoporous silica (MS) spheres as nanoreactors. The binding ability of CDs towards metal ions was examined by comparing the fluorescence intensities of CDs before and after the addition of the metal ions. The addition of Cu2+ cations leads to their absorption on the surface of CDs and the significant fluorescence quench of CDs (turn-off). The resulting in CDs-Cu2+ system was found to be sensitive to L-Cys. The addition of L-Cys not only serves to shelter the CDs effectively from being quenched, but also to reverse the quenching and restore the fluorescence (turn-on) due to its ability to remove Cu2+ from the surface of CDs. This method is facile, rapid, low cost, and environment-friendly. A detection limit as low as 2.3 x 10(-8) M for Cu2+ and 3.4 x 10(-10) M for L-Cys is obtained, which is promising for biological applications. (C) 2013 Elsevier B.V. All rights reserved.