Evaluation of a carbon nanotube-titanate nanotube nanocomposite as an electrochemical biosensor scaffold

Xiaoqiang Liu*, Rui Yan, Jiamei Zhang, Jie Zhu, Danny K Y Wong

*Corresponding author for this work

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

A significant aspect of this work is the development of a multi-wall carbon nanotube (MWCNT)-titanate nanotube (TNT) nanocomposite to serve as a biocompatible scaffold with high conductivity on a biosensor surface. Unlike other scaffolds consisting of MWCNTs alone or TNTs alone, the MWCNT-TNT nanocomposite synergistically provides excellent biocompatibility, good electrical conductivity, low electrochemical interferences and a high signal-to-noise ratio. For comparison, after characterising a scaffold consisting of MWCNTs alone, TNTs alone and a MWCNT-TNT nanocomposite using several spectroscopic techniques, the analytical performance of a horseradish peroxidase (HRP) electrochemical biosensor was evaluated using cyclic voltammetry and differential pulse voltammetry. The scaffold consisting of MWCNTs alone displayed a high background charging current, a low signal-to-noise ratio and distinct electrochemical interference from its surface functional groups. In contrast, the direct electrochemistry and the catalytic capability of HRP at MWCNT-TNT modified biosensors towards H2O2 was demonstrated to be ~51% and ~144% enhanced, respectively, compared to those at TNT modified biosensors. Meanwhile, MWCNT-TNT nanocomposite modified HRP biosensors also exhibited higher sensitivity (4.42μAmM-1) than TNT modified HRP biosensors (1.48μAmM-1). The above superior performance was attributed to the improved properties of MWCNT-TNT nanocomposite as biosensor scaffold compared to its two individual components by complementing each component and synergistically sustaining the characteristic features of each component.

Original languageEnglish
Pages (from-to)208-215
Number of pages8
JournalBiosensors and Bioelectronics
Volume66
DOIs
Publication statusPublished - 15 Apr 2015

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Keywords

  • Catalytic capability
  • Direct electrochemistry
  • Electrochemical biosensor
  • Immobilisation materials
  • MWCNT-TNT nanocomposites

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