Direct electrochemistry-based hydrogen peroxide biosensor formed from single-layer graphene nanoplatelet-enzyme composite film

Qing Lu, Xiaochen Dong, Lain-Jong Li, Xiao Hu*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

88 Scopus citations

Abstract

A novel electrochemical sensing system for direct electrochemistry-based hydrogen peroxide biosensor was developed that relied on the virtues of excellent biocompatibility, conductivity and high sensitivity to the local perturbations of single-layer graphene nanoplatelet (SLGnP). To demonstrate the concept, the horseradish peroxidase (HRP) enzyme was selected as a model to form the SLGnP-TPA (tetrasodium 1,3,6,8-pyrenetetrasulfonic acid)-HRP composite film. The single-layer graphene composite film displayed a pair of well-defined and good reversible cyclic voltammetric peak for Fe(III)/Fe(II) redox couple of HRP, reflecting the enhancement for the direct electron transfer between the enzyme and the electrode surface. Analysis using electrochemical impedance spectroscopy (EIS) revealed that electrostatic attractions existed between graphene monolayers and enzyme molecules. The intimate graphene and enzyme interaction was also observed using scanning electron microscopy (SEM), which resulted in the special properties of the composite film. Ultraviolet visible spectroscopy (UV-vis) indicated the enzyme in the composite film retained its secondary structure similar to the native state. The composite film demonstrated excellent electrochemical responses for the electrocatalytic reduction of hydrogen peroxide (H2O2), thus suggesting its great potential applications in direct electrochemistry-based biosensors. Crown

Original languageEnglish (US)
Pages (from-to)1344-1348
Number of pages5
JournalTalanta
Volume82
Issue number4
DOIs
StatePublished - Sep 15 2010

Keywords

  • Direct electrochemistry-based biosensor
  • Horseradish peroxidase
  • Single-layer graphene nanoplatelet
  • Tetrasodium 1,3,6,8-pyrenetetrasulfonic acid

ASJC Scopus subject areas

  • Analytical Chemistry

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