INFIQC   05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
artículos
Título:
Electrooxidation of DNA at glassy carbon electrodes modified with multi-wall carbon nanotubes dispersed in chitosan
Autor/es:
SOLEDAD BOLLO, NANCY F. FERREYRA, GUSTAVO A. RIVAS
Revista:
ELECTROANALYSIS
Referencias:
Año: 2006
ISSN:
1040-0397
Resumen:
We report on the analytical performance of glassy carbon (GCE) electrodes modified with a dispersion of multiwall carbon nanotubes (CNT) in chitosan (CHIT) for the quantification of DNA.T he electroanalytical response of the resulting electrodes was evaluated using differential pulse voltammetry, while the electrochemical reactivity of the film surface was characterized using scanning electrochemical microscopy.Different treatments of the modified GCE were evaluated to improve the stability of the film and the accumulation of DNA.T he guanine oxidation signal of double stranded calf-thymus DNA after 3-min accumulation was 20 times higher at GCE/CHIT-CNT cross-linked with glutaraldehyde (GTA) than at bare GCE, while the peak potential was around 45 mV less positive.T he guanine oxidation signal demonstrated to be highly reproducible, with 3.4% RSD for 5 different electrodes.The treatment with sodium hydroxide demonstrated to be not effective since the resulting films were less stable and the guanine oxidation signal was ten times smaller compared to electrodes prepared with the GTA treated films.T he effect of chitosan molecular weight used to prepare the dispersion and the amount of carbon nanotubes dispersed were evaluated.T he response of single stranded DNA and oligo(dG)15 is also discussed.