Journal
BIOSENSORS & BIOELECTRONICS
Volume 55, Issue -, Pages 187-194Publisher
ELSEVIER ADVANCED TECHNOLOGY
DOI: 10.1016/j.bios.2013.12.019
Keywords
G-quadruplex; DNA-templated organic synthesis (DTS); Click chemistry; Copper ion; Crystal violet (CV)
Categories
Funding
- National Natural Science Foundation of China [21222507, 21175036, 21235002, 21190044]
- Foundation for Innovative Research Groups of NSFC [21221003]
- National Basic Research Program of China (973 Program) [2009CB421601, 2011CB911002]
- Program for New Century Excellent Talents in University [NCET-10-0366]
- Ph.D. Programs Foundation of the Ministry of Education of China [20120161110025]
Ask authors/readers for more resources
A novel homogenous fluorescent sensor for signal-on detection of Cu2+ has been developed based on intra-molecular G-quadruplex formed by DNA-templated click reaction and crystal violet (CV) as labelfree signal reporter. The clickable DNA probe consists of two G-rich strands (A and B) bearing azide and alkyne group, respectively, and a template strand (C) locating two proximate reactants by pairing with A and B. The sequences of A and B are derived from asymmetric split of the G-quadruplex sequence (TTAGGG)(4). In the presence of Cu2+, the whole G-quadruplex sequence A-B is generated by chemical ligation of A and B via copper ion-catalyzed alkyne-azide cycloaddition, then released from template by toehold strand displacement, and consequently forming a stable intra-molecular G-quadruplex, which binds with CV to generate a strong fluorescent signal. Oppositely, weak fluorescence was obtained without Cu2+ because of unstable intermolecular G-quadruplex formed by A and B and lack of lateral loop connection. Therefore, the Cu2+ can be sensitively and specifically detected by the fluorescence of the CV-stained G-quadruplex with a low detection limit of 65 nM and a linear range of 0.1-3 mu M. This method rationally integrated the DNA-templated synthesis and G-quadruplex structure-switch, presenting a simple and promising approach for biosensor development. (C) 2013 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available