GLASSY CARBON ELECTRODES MODIFIED WITH A DISPERSION OF MULTI-WALL CARBON NANOTUBES IN DOPAMINE-FUNCTIONALIZED POLYETHYLENIMINE CHARACTERIZATION AND ANALYTICAL APPLICATIONS FOR NICOTINAMIDE ADENINE DINUCLEOTIDE QUANTIFICATION

AURÉLIEN GASNIER ; M. LAURA PEDANO; FABIANA GUTIÉRREZ; PIERRE LABBÉ; GUSTAVO RIVAS; M. DOLORES RUBIANES

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2012 vol. 71 p. 73 - 73

We report the characterization of a dispersion of multi-wall carbon nanotubes (CNT) in a solution of polyethylenimine (PEI) functionalized with dopamine (Do), the electrochemical behavior of glassy carbon electrodes (GCE) modified with the resulting dispersion, and its analytical application for the highly sensitive quantification of NADH without fouling of the surface. The dispersion was obtained by sonicating for 60 min 1.0 mg CNT in 1.0 mL of 1.0 mg/mL PEI-Do solution prepared in 50/50 (v/v) ethanol/water. The presence of Do covalently bonded to PEI promotes hydrophobic π interactions with the CNT walls and improves significantly the dispersability of CNT in this mixture. The dispersion is highly stable since after 2 months resting at room temperature no phase separation was observed. This dispersion was drop-coated over GCE, and after solvent evaporation, a very reproducible and uniform coverage was obtained