Issue 34, 2021

Graphene-coated copper-doped ZnO quantum dots for sensitive photoelectrochemical bioanalysis of thrombin triggered by DNA nanoflowers

Abstract

This work reports a photoelectrochemical (PEC) biosensing platform for the sensitive and specific screening of thrombin by using graphene oxide-coated copper-doped zinc oxide quantum dots (Cu0.3Zn0.7O-GO QDs) as the photoactive materials and glucose oxidase-encapsulated DNA nanoflowers (GOx-DFs) for signal amplification. Interestingly, the coated graphene oxide nanosheets on the surface of the Cu0.3Zn0.7O QDs could cause the charge to transfer rapidly and ameliorate the photocorrosion. The doped copper into the quantum dots could enhance the absorption of visible light by tuning the band gap of ZnO QDs, therefore increasing the photocurrent under visible irradiation. Upon addition of target thrombin, a sandwiched reaction was carried out between thrombin aptamer and GOx-DFs, accompanying the formation of nanocomposites with the magnetic microparticles (MMPs)/thrombin/GOx-DFs. Followed by magnetic separation, the carried GOx oxidized glucose to H2O2, thus resulting in the increasing photocurrent of the Cu0.3Zn0.7O-GO QD-modified electrode. Under optimum conditions, the developed PEC biosensing platform exhibited good analytical performance with a linear range of 50–10 000 fM thrombin and a limit of detection of 29 fM. Impressively, our strategy offers a new horizon in developing bridge-connected graphene-coated nanomaterials and novel signal amplification strategy for the development of PEC biosensors.

Graphical abstract: Graphene-coated copper-doped ZnO quantum dots for sensitive photoelectrochemical bioanalysis of thrombin triggered by DNA nanoflowers

Supplementary files

Article information

Article type
Paper
Submitted
02 juil. 2021
Accepted
31 juil. 2021
First published
02 août 2021

J. Mater. Chem. B, 2021,9, 6818-6824

Graphene-coated copper-doped ZnO quantum dots for sensitive photoelectrochemical bioanalysis of thrombin triggered by DNA nanoflowers

Y. Li, W. Wang, H. Gong, J. Xu, Z. Yu, Q. Wei and D. Tang, J. Mater. Chem. B, 2021, 9, 6818 DOI: 10.1039/D1TB01465J

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