Issue 23, 2019

Exonuclease-assisted target recycling for ultrasensitive electrochemical detection of microRNA at vertically aligned carbon nanotubes

Abstract

As an important biomarker for early disease diagnosis, microRNA-21 (miRNA-21) has attracted considerable attention owing to its accurate detection. Herein we combine the one-step biorecognition reaction at a vertically aligned nanostructure-based biosensor with the T7 exonuclease (Exo)-assisted target recycling to develop a novel electrochemical bioassay method for miRNA-21 detection. The vertically aligned nanointerface is constructed through the covalent attachment of terminally carboxylated single-walled carbon nanotubes (SWCNTs) at an aryldiazonium salt-modified electrode, which enables the noncovalent adsorption of a ferrocene-labeled single-stranded signal DNA to obtain the biosensor. Upon its incubation with a target miRNA-21 solution, DNA/RNA hybridized duplexes will form and release from the electrode surface, leading to the corresponding electrochemical signal decrease of the biosensor. Moreover, this biorecognition reaction can also trigger the T7 Exo-assisted target recycling to achieve great signal amplification. Together with the highly efficient biorecognition and excellent electron transfer promotion at the vertically aligned SWCNTs, this biosensor exhibits a wide linear range varying from 0.01 to 100 pM and a low detection limit down to 3.5 fM. Considering its obvious performance superiority and convenient manipulations, this vertically aligned SWCNT-based electrochemical biosensing method has extensive potential for practical applications.

Graphical abstract: Exonuclease-assisted target recycling for ultrasensitive electrochemical detection of microRNA at vertically aligned carbon nanotubes

  • This article is part of the themed collection: Nanocarbons

Supplementary files

Article information

Article type
Paper
Submitted
24 mar 2019
Accepted
26 mai 2019
First published
27 mai 2019

Nanoscale, 2019,11, 11262-11269

Exonuclease-assisted target recycling for ultrasensitive electrochemical detection of microRNA at vertically aligned carbon nanotubes

Z. Chen, Y. Xie, W. Huang, C. Qin, A. Yu and G. Lai, Nanoscale, 2019, 11, 11262 DOI: 10.1039/C9NR02543J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements