INSTITUTO DE QUIMICA, FISICA DE LOS MATERIALES, MEDIOAMBIENTE Y ENERGIA
Unidad Ejecutora - UE
Electrochemical sensing platform based on polyelectrolyte-surfactant supramolecular assemblies incorporating carbon nanotubes.
M.L. CORTEZ; M. CEOLIN; O. AZZARONI; F. BATTAGLINI
AMER CHEMICAL SOC
Lugar: Washington; Año: 2011 vol. 83 p. 8011 - 8011
The characterization and application of a polyelectrolyte surfactant supramolecular assembly formed by poly- (allylamine) and dodecyl sulfate (PADS) on a screen-printed graphite electrode for the preparation of electrochemical sensing platforms are presented. The system was characterized by X-ray reflectometry (XRR) and grazing-incidence small-angle X-ray scattering (GISAXS) and tested with four benchmark electrochemical probes undergoing different electron-transfer mechanisms on carbon: ferrocyanide, hexaammineruthenium, ascorbic acid, and dopamine. The polyelectrolyte acts as a scaffold favoring the incorporation of the ferrocyanide, an ion oppositely charged to poly(allylamine). Also, its ability to incorporate carbon nanotubes (CNT) is presented. The composite material PADSCNT is able to electrocatalyze the oxidation of dopamine, allowing its detection at micromolar levels in the presence of 100 times higher concentrations of ascorbate and it is shown to be stable, while XRR and GISAXS results confirm a lamellar structure with well-defined domains, not perturbed by the presence of the CNT. The dispersion is easily prepared in aqueous solution and could facilitate the processing of the CNT with an efficient loading and yielding a more robust carbon-based material for sensing applications