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conferenceseries.com
Volume 8, Issue 2 (Suppl) J Biosens Bioelectron, an open access journal
ISSN: 2155-6210 Euro Biosensors 2017
July 10-11, 2017
July 10-11, 2017 Berlin, Germany
7th Euro Biosensors
and Bioelectronics Conference
Application of twin-working electrode cell in characterizing biological electron mediators
Mahamudul Hassan1,2 , Ka Yu Cheng1,3, Goen Ho1 and Ralf Cord-Ruwisch 1
1Murdoch University, Australia
2University of Chittagong, Bangladesh
3CSIRO Land and Water, Australia
Electron mediators often play a key role in facilitating microbial extracellular electron transfer (EET) to oxygen or insoluble
compounds. This study aims at developing a novel electrochemical cell consisting of two closely (250 µm) mounted working
electrodes (WEs), hence Twin-WE; to detect and quantify redox active compounds in a micro-scale (304 µL) environment. A fixed
voltage window between two WEs using common counter and reference electrodes was maintained and the individual currents
of both WEs were monitored. To detect electron mediators, an optimized voltage window (50 mV) was shifted through a defined
potential range (between –1 V and +0.5 V vs. Ag/AgCl) by changing a fixed voltage step (12.5 mV) after the establishment of steady
equilibrium current in both WEs. When the voltage window was maintained at the midpoint potential of a mediator, concurrent
oxidation and reduction of the mediator occurred as evidence by the concurrent maximal anodic and cathodic current recorded
at the two WEs. The electrical current difference plot against the potential scale enabled the identification (by peak location in
the potential scale) and quantification (by peak height) of the mediators tested. Our technique enabled a precise determination
of riboflavin, anthraquinone-2, 6-disulfonate (AQDS) and two mediators from a pyocyanin producing Pseudomonas aeruginosa
(WACC 91) culture both individually and from their mixture. The described Twin-WE cell device is suitable for studying microbial
electron transfer processes under a simulated redox environment which prevails in natural habitat. The bio-electrochemical principle
underpinning this new method may also be useful for advancing biosensor development.
Biography
Mahamudul Hassan has completed his BSc (honors) and MS in Microbiology from University of Chittagong, Bangladesh. Currently, he is pursuing his PhD at
Murdoch University and he aims to investigate the role of electron mediators in microbial extracellular electron transfer (EET) processes.
Mahamudul Hassan et al., J Biosens Bioelectron 2017, 8:2(Suppl)
DOI: 10.4172/2155-6210-C1-033