Glycerol Oxidation By NAD+-Dependent Enzymatic Systems
This paper will focus in the development of the bioanode to fully oxidize glycerol. The glycerol conversion to CO2 could be done by a sequential oxidation with nicotinamide adenine dinucleotide (NAD+/NADH)-dependent enzymes such as alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (AlDH) and oxalate oxidase (OxOx), lignin peroxidase (Lig) or Pt-Ru nanostructured catalyst.2 The anode design makes use of electrodeposited methylene green (MG) as catalyst toward the oxidation of NADH to NAD+ in order to minimize the overpotential of this reaction and provide the cofactor to the enzymes.3 Also, the NAD+/NADH cofactor will be tethered on the electrode surface by pyrene butanoic acid succinimidyl ester (PBSE) linker to the carbon nanotube-based material.4 Multiwalled carbon nanotube (MWCNTs)-based bucky papers are promising electrode materials for biofuel cells because of the combination of the MWCNTs high electrical conductivity, mechanical strength, thermal stability and chemical stability.5 On the bucky paper surface, the enzymes are immobilized in a polymeric chitosan-carbon nanotubes (CNTs) matrix after MG electrodeposition. In the end, two bioanode designs, a fully enzymatic and a hybrid (employing Pt-Ru catalyst) could be constructed, characterized and compared for full glycerol oxidation to CO2.
The glycerol-based bioanode can later be integrated to the lactate/glucose sensor design to induce reverse-iontophoresis of glucose from interstitial fluids. The utilization of glycerol in a lactate sensor will facilitate the storage of the biofuel in the patch-sensor design due to its low evaporation rate and high viscosity. The sensor/biofuel cell will be user-friendly and non-invasive lactate/glucose sampling.
(1) W. Jia, A. J. Bandodkar, G. Valdeìs-Ramírez, J. R. Windmiller, Z. Yang, J. Ramírez, G. Chan, and J. Wang. Anal. Chem. 2013, 85, 6553−6560.
(2) A. Falase, C. Lau, P. Atanassov, R. Arechederra, Z. Zulic and S. Minteer. 217th ECS Meeting, Abstract #419, The Electrochemical Society 2010.
(3) V. Svoboda, C. Rippolz, M. J. Cooney, B. Y. Liaw. The Journal of Electrochemical Society 2007, 154, D113
(4) R. J. Chen, Y. Zhang, D. Wang, H. Dai. Journal of the American Chemical Society 2001, 123, 3838.
(5) H. Dai, J. Kong, C. Zhou, N. Franklin, T. Tombler, A.Cassell, S. Fan, and M. Chapline. Journal of Physical Chemistry B 1999, 103, 11246.