Glassy carbon electrodes modified with CNT dispersed in chitosan: analytical applications for sensing dna- methylene blue interaction

PAULINA ARIAS; NANCY F. FERREYRA; GUSTAVO A. RIVAS; SOLEDAD BOLLO

JOURNAL OF ELECTROANALYTICAL CHEMISTRY - (Print)

ELSEVIER SCIENCE SA

Año: 2009 vol. 634 p. 123 - 126

1572-6657

In this work we report the optimization of a chitosan (CHI) and carbon nanotubes (CNT) modified electrode, CNT-CHI, to study the dsDNA interaction with methylene blue (MB), a well-known DNA intercalator. The analytical signal was the reduction current of the MB associated with the dsDNA confined at CNTCHI modified glassy carbon electrode. The selected CNT-CHI film stabilizing treatment was immersion for 2 s in a 0.20% GTA solution. The effect of ionic strength was also analyzed, concluding that high concentration of NaCl (90 mM) benefits the intercalative process. Below these conditions, a linear response between intensity current and MB concentration was obtained. In conclusion, modifying the initial conditions of the assembling GCE/CHI-CNT/dsDNA electrode the intercalative process was favored opening a fast and cheap possibility to evaluate the toxicity of new synthesized molecules.