Jump to main content
Jump to site search

Issue 9, 2021
Previous Article Next Article

Electrochemical detection of microRNA-21 based on a Au nanoparticle functionalized g-C3N4 nanosheet nanohybrid as a sensing platform and a hybridization chain reaction amplification strategy

Author affiliations

Abstract

Here, a sensitive sandwich-type electrochemical biosensor for microRNA-21 detection was reported. It was based on the use of a Au NP functionalized graphite-like carbon nitride nanosheet (g-C3N4 NS) nanohybrid (Au NPs–g-C3N4 NS) as a sensing platform and DNA concatemers containing methylene blue (MB) as a signal probe. The signal probe was prepared by using two different single strand DNAs with a complementary sequence (one of them labeled with MB at the 3′ end) to form long concatemers via continuous hybridization chain reaction (HCR); thus numerous MB signal molecules were loaded on long concatemers. The biosensor was fabricated following the next step: a thiolated hairpin probe (HP) was first immobilized on the surface of the glassy carbon electrode (GCE) modified with a Au NPs–g-C3N4 NS nanohybrid. After it was blocked with MCH, the modified electrode was sequentially hybridized with microRNA-21 and a signal probe, respectively. As a result, a sandwich structure of HP–microRNA–signal probe covered the surface of the modified electrode. Differential pulse voltammetry (DPV) was employed to measure the sensing signal in phosphate buffered solution (0.10 M PBS, pH 7.4). The experimental conditions were optimized such as the hybridization time and the amount of g-C3N4 NS. The proposed biosensor exhibited a wide linear response range (1.0 fM to 500 nM) and a low limit of detection (0.33 fM; at S/N = 3) under the optimal conditions. Meanwhile, the biosensor could discriminate single base mismatched microRNA-21, indicating that the biosensor possessed high selectivity.

Graphical abstract: Electrochemical detection of microRNA-21 based on a Au nanoparticle functionalized g-C3N4 nanosheet nanohybrid as a sensing platform and a hybridization chain reaction amplification strategy

Back to tab navigation

Supplementary files

Article information


Submitted
07 Jan 2021
Accepted
26 Feb 2021
First published
02 Mar 2021

Analyst, 2021,146, 2886-2893
Article type
Paper

Electrochemical detection of microRNA-21 based on a Au nanoparticle functionalized g-C3N4 nanosheet nanohybrid as a sensing platform and a hybridization chain reaction amplification strategy

Y. Wang, M. Li and Y. Zhang, Analyst, 2021, 146, 2886
DOI: 10.1039/D1AN00029B

Social activity

Search articles by author

Spotlight

Advertisements