Enhanced NADH Oxidation Using Polytyramine/Carbon Nanotube Modified Electrodes for Ethanol Biosensing

Thomas A. Wilson, Mustafa M Musameh, Ilias L Kyratzis, Jie Zhang, Alan M. Bond, Milton T.W. Hearn

Research output: Contribution to journalArticleResearchpeer-review

8 Citations (Scopus)

Abstract

Polytyramine (PT) has been electro-deposited onto multi-walled carbon nanotube (MWCNT) modified glassy carbon (GC) electrodes via oxidation of tyramine in 0.1M H3PO4 by cycling the potential over the range of -400mV to 1300mV (versus Ag/AgCl). The reactivity of the resulting chemically-modified electrodes was characterized using cyclic voltammetry in the presence and absence of reduced nicotinamide adenine dinucleotide (NADH). The modified electrodes displayed electrochemical activity due to the formation of quinone species and were catalytically active towards NADH oxidation by lowering the oxidation peak potential by 170mV compared to the value of the MWCNT modified electrode with a peak potential of 180±10mV (versus Ag/AgCl). The MWCNT/PT surface was further characterized using SEM and XPS methods, which indicated that a thin polymeric film had been formed on the electrode surface. The present work demonstrates the advantage of using PT as a platform that combines both the immobilization of alcohol dehydrogenase (ADH) and the mediation of NADH oxidation at a low overpotential essential to the design of high performance ethanol biosensors, all within an easily electropolymerizable film. The resulting biosensor displayed an ethanol sensitivity of 4.28±0.06μAmM-1cm-2, a linear range between 0.1mM and 0.5mM and a detection limit of 10μM.

Original languageEnglish
Pages (from-to)1985 – 1993
Number of pages9
JournalElectroanalysis
Volume29
Issue number8
DOIs
Publication statusPublished - 2017

Keywords

  • Biosensor
  • Ethanol
  • Mediator
  • NADH
  • Tyramine

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