Owing to their high conductivity, inertness and electroactive surface area, graphene and carbon nanotube are widely used for the design of biosensors and biofuel cells [1,2].

Concerning the bioconversion of energy, an example of biofuel cell based on carbon nanotube/enzyme compressions, employing glucose oxidase for glucose oxidation, and laccase for oxygen reduction will be reported as well as its one-year stability [3]. Recent advances in the elaboration of enzyme electrodes based on carbon nanotube coatings functionalized by electropolymerized films or pi-stacked compounds will be presented for the design of biocathodes. In particular, anthraquinone-functionalized reduced oxide graphene nanosheets were thus stacked on carbon nanotube electrodes and successfully used for the non-covalent attachment of laccase and its electrical wiring [4]. In addition, the efficient immobilization and orientation of bilirubin oxidase on multi-walled carbon nanotube electrodes by using pi-stacked porphyrins as a direct electron transfer promoter will be reported. Different types of porphyrins were investigated to identify some effects of the porphyrin structure on the immobilization and wiring of the enzyme [5]. Another alternative concerns the non-covalent functionalization of carbon nanotube electrode with biomimetic model of the horseradish peroxidase active site. The electrogeneration of a polypyrrole film N-substituted by imidazole group on nanotube coating allows the coordination of protoporphine IX iron(III) and its use for the electroreduction of hydrogen peroxide [6]. The combination of carbon nanotube coating and an electropolymerized polypyrrole film of a protein: concanavalin A is also an original strategy for the non-covalent immobilization of glycoproteins via specific interactions with polymerized concanavalin A. This approach was exploited for the biofunctionalization of buckypapers obtained by cross-linking of carbon nanotubes by bis pyrene derivative [7].   

 Increased attention has been also given to the combination of carbon nanotubes with polynorbornene films. Owing to the conductivity of carbon nanotubes, the formation of BP obtained by filtration of CNT dispersion, represents an attractive way of creating a new kind of electrode or membrane. Flexible bucky paper electrodes were thus easily produced by mixing polynorbornene polymers bearing pyrene groups and multi-walled carbon nanotubes both dispersed in dimethylformamide and then filtering the mixture through a PTFE membrane [8].  In addition, the flexibility and mechanical resistance of these buckypapers were modulated by changing the length of the linear polynorbornene polymers. These bucky paper electrodes were modified by enzymes and applied to the electroenzymatic reduction of oxygen in phosphate buffer (pH 5).

References

 

1. M. Holzinger, A. Le Goff, S. Cosnier. Electrochim. Acta, 82 (2012) 179-190.
2. S. Cosnier, A. Le Goff, M. Holzinger.  Electrochem. Commun, 38 (2014) 19-23
3. B. Reuillard, C. Abreu, N. Lalaoui, A. Le Goff, M. Holzinger, O. Ondel, F. Buret, S. Cosnier. Bioelectrochemistry, 106 (2015) 73-76.
4. N. Lalaoui, A. Le Goff, M. Holzinger, M. Mermoux, S. Cosnier. Chem. Eur. J., 21 (2015) 3198-3201.
5. N. Lalaoui, A. Le Goff, M. Holzinger, S. Cosnier. Chem. Eur. J.,21 (2015)16868-16873.
6. B. Reuillard, S. Gentil, M. Carrière, A. Le Goff, S. Cosnier. Chem. Sci., 6 (2015) 5139-5143.
7. K. Elouarzaki, M. Bourourou, M. Holzinger, A. Le Goff , R. S. Marks, S. Cosnier. Energy Environ.Sci.. 8 (2015)  2069-2074.
8. S. Cosnier, R. Haddad, D. Moatsou, R. K. O'Reilly. Carbon, 93 (2015) 713-718.