Next Article in Journal
Underwater Robot Task Planning Using Multi-Objective Meta-Heuristics
Next Article in Special Issue
Electrochemical Genosensing of Circulating Biomarkers
Previous Article in Journal
A Reconfigurable Readout Integrated Circuit for Heterogeneous Display-Based Multi-Sensor Systems
Previous Article in Special Issue
DNA Sequencing Sensors: An Overview
Article Menu
Issue 4 (April) cover image

Export Article

Open AccessArticle
Sensors 2017, 17(4), 760;

An Exonuclease I-Based Quencher-Free Fluorescent Method Using DNA Hairpin Probes for Rapid Detection of MicroRNA

State Key Laboratory of Medical Genetics & School of Life Sciences, Central South University, Changsha 410013, China
Authors to whom correspondence should be addressed.
Received: 3 February 2017 / Revised: 26 March 2017 / Accepted: 31 March 2017 / Published: 3 April 2017
(This article belongs to the Special Issue Genosensing)
Full-Text   |   PDF [2003 KB, uploaded 6 April 2017]   |  


MicroRNAs (miRNAs) act as biomarkers for the diagnosis of a variety of cancers. Since the currently used methods for miRNA detection have limitations, simple, sensitive, and cost-effective methods for the detection of miRNA are required. This work demonstrates a facile, quencher-free, fluorescence-based analytical method for cost-effective and sensitive detection of miRNA using a super 2-aminopurine (2-AP)-labeled hairpin probe (HP) and exonuclease I activity. Specifically, the fluorescence of 2-AP is strongly quenched when it is incorporated within DNA. In the presence of a target miRNA, HP attains an open conformation by hybridizing with the target miRNA to form a double-stranded structure with a protruding 3′-terminus. Next, the digestion of the protruding 3′-terminus is triggered by exonuclease I, during which 2-AP is released free in solution from the DNA, thereby increasing fluorescence. This method is highly sensitive, with a detection limit of 0.5 nM—10 times lower than a previously reported quencher-free fluorescence method. Furthermore, this method has potential applications in clinical diagnosis and biomedical research. View Full-Text
Keywords: microRNA; quencher-free; exonuclease I; 2-aminopurine; hairpin probe microRNA; quencher-free; exonuclease I; 2-aminopurine; hairpin probe

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Ma, C.; Liu, H.; Wu, K.; Chen, M.; Zheng, L.; Wang, J. An Exonuclease I-Based Quencher-Free Fluorescent Method Using DNA Hairpin Probes for Rapid Detection of MicroRNA. Sensors 2017, 17, 760.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top