Electrooxidation of DNA at glassy carbon electrodes modified with multi-wall carbon nanotubes dispersed in chitosan

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

WILEY-V C H VERLAG GMBH

Año: 2007 vol. 19 p. 833 - 833

font size="1" face="AdvTTR"> 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 electrode