Development of multifunctional bioelectrocatalytic films for oxidation of ethanol
|Barbara Kowalewska , Paweł J. Kulesza|
University of Warsaw, Department of Chemistry, Pasteura 1, Warsaw, Warszawa 02-093, Poland
The main goal of our research was to design, characterize and evaluate of utility distinct dehydrogenase containing multi-component bi-enzymatic and well organized bioelectrocatalytic systems capable of effective oxidation of ethanol in neutral media.
In our work, we have exploited unique characteristics of multi-walled carbon nanotubes (CNTs) [1,2] to construct the efficient anodic bioelectrocatalytic system of potential utility for biofuel cells and biosensors. Some attention has been also paid to the choice of the modifying agent poly(diallyldimethylammonium chloride) (PDDA) used to stabilize CNTs. While PDDA seems to form stable ultra-thin layers on CNTs, it is not expected to serve as a good charge (electron) mediator but it is reasonable to expect that PDDA would interact or attract electrostatically with negatively charged sites of the enzyme (or combination of dehydrogenase enzymes). Our highly porous CNT-based films have presumably acted as three-dimensional network of nanowires around the enzyme molecules and have promoted the efficient electron transfer. On the whole, combination of PDDA-modifed MWCNTs and two distinct dehydrogenase enzymes within the film has produced a catalytic system capable of oxidation of ethanol at fairly low potentials (ca. 0.1 V vs Ag/AgCl). Kinetic parameters including heterogeneous rate constants at different applied potentials as well as an apparent Michaelis-Menten constant (KMapp ~ 0.33 mM) were also determined. Among important issues are good stability and reproducibility of responses both under voltammetric and amperometric conditions.
 B. Kowalewska, P.J. Kulesza, Electroanalysis, 21 (2009) 351.
 B. Kowalewska, M. Skunik, K. Karnicka, K. Miecznikowski, M. Chojak, G. Ginalska, A. Belcarz, P.J. Kulesza, Electrochim. Acta 53 (2008) 2404.
Presentation: Keynote lecture at SMCBS'2011 International Workshop, by Paweł J. Kulesza
See On-line Journal of SMCBS'2011 International Workshop
Submitted: 2011-08-31 17:44 Revised: 2011-08-31 17:50