Enhanced NADH Oxidation Using Polytyramine/Carbon Nanotube Modified Electrodes for Ethanol Biosensing. Issue 8 (26th May 2017)

• Record Type: Journal Article
• Authors: Wilson, Thomas A.; Musameh, Mustafa; Kyratzis, Ilias L.; Zhang, Jie; Bond, Alan M.; Hearn, Milton T. W.
• Is Part Of: Electroanalysis. Volume 29:Issue 8(2017)
• Page Start: 1985
• Page End: 1993
• Publication Date: 2017-05-26
• Subjects: NADH -- mediator -- tyramine -- biosensor -- ethanol; Electrochemical analysis -- Periodicals; Chemistry, Analytical -- Periodicals; Electrochemistry -- Periodicals; 543.4
• DOI: 10.1002/elan.201700146
• Languages: English
• ISSNs: 1040-0397

Abstract

Abstract: Polytyramine (PT) has been electro‐deposited onto multi‐walled carbon nanotube (MWCNT) modified glassy carbon (GC) electrodes via oxidation of tyramine in 0.1 M H3 PO4 by cycling the potential over the range of −400 mV to 1300 mV ( 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 170 mV compared to the value of the MWCNT modified electrode with a peak potential of 180±10 mV ( 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±0.06 μA mM −1 cm −2, a linear range between 0.1 mM and 0.5 mM and a detection limit of 10 μM. Abstract :