期刊
ANALYTICAL BIOCHEMISTRY
卷 492, 期 -, 页码 56-62出版社
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.ab.2015.09.011
关键词
Electrochemical DNA biosensor; Copper complex; Graphene; Square-wave voltammetry
资金
- National Natural Science Foundation of China [51273155]
- Fundamental Research Funds for the Central Universities [2014-Ia-030]
We demonstrate a novel protocol for sensitive in situ label-free electrochemical detection of DNA hybridization based on copper complex ([Cu(phen)(2)](2+), where phen = 1,10-phenanthroline) and graphene (GR) modified glassy carbon electrode. Here, [Cu(phen)(2)](2+) acted advantageously as both the electrochemical indicator and the anchor for probe DNA immobilization via intercalative interactions between the partial double helix structure of probe DNA and the vertical aromatic groups of phen. GR provided large density of docking site for probe DNA immobilization and increased the electrical conductivity ability of the electrode. The modification procedure was monitored by electrochemical impedance spectroscopy (EIS). Square-wave voltammetry (SWV) was used to explore the hybridization events. Under the optimal conditions, the designed electrochemical DNA biosensor could effectively distinguish different mismatch degrees of complementary DNA from one-base mismatch to noncomplementary, indicating that the biosensor had high selectivity. It also exhibited a reasonable linear relationship. The oxidation peak currents of [Cu(phen)(2)](2+) were linear with the logarithm of the concentrations of complementary target DNA ranging from 1 x 10(-12) to 1 x 10(-6) M with a detection limit of 1.99 x 10(-13) M (signal/noise = 3). Moreover, the stability of the electrochemical DNA biosensor was also studied. (C) 2015 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据