Département de chimie moléculaire

One challenging goal for the development of biosensors is the conception of three dimensional biostructures on electrode surfaces. In this context, single-walled carbon nanotube coatings (SWCNTs), functionalized by biotin groups, were investigated to develop 3D conductive nanostructures allowing a post-functionalization by biol. macromols. This specific anchoring of biomols. was carried via the affinity interactions using the avidin-biotin system. For this purpose, a biotinylated pyrene was specially synthesized to develop a non-covalent functionalization based on $π$-interactions between pyrene and the nanotube sidewall. SWCNT coatings were also biotinylated via electropolymn. of biotin-pyrrole derivs. at 0.95 V in CH3CN electrolyte. The resulting biotinylated SWCNTs were modified by an avidin protein via affinity interactions and characterized with SEM. The biofunctionalization by a biotinylated glucose oxidase (GOX) was performed by successive incubation in avidin and GOX aq. solns. via avidin bridges. The efficiency of the enzyme anchoring was examd. through the electro-enzymic activity of the modified electrodes towards the detection of glucose at 0.7 V vs. SCE. The glucose sensitivity and max. c.d. were 1.6 mAM-1 cm-2 and 131 $μ$Acm-2 resp. for pyrene biotin-SWCNT electrode and 2.5 mAM-1 cm-2 and 178 $μ$Acm-2 resp. for the poly(pyrrole biotin)-SWCNT. [on SciFinder(R)]