Immobilization of DNA at Glassy Carbon Electrodes. A critical Study of the Adsorbed Layer.

M. L. PEDANO ; G. A. RIVAS

MOLECULAR DIVERSITY PRESERVATION INTERNATIONAL-MDPI

Lugar: Basel; Año: 2005 vol. 5 p. 424 - 424

font face="Times New Roman">In this work we present a critical study of the nucleic acid layer immobilized at glassy carbon electrodes. Different studies were performed in order to assess the nature of the interaction between DNA and the electrode surface. The adsorption and electrooxidation of DNAdemonstrated to be highly dependent on the surface and nature of the glassy carbon electrode. TheDNA layer immobilized at a freshly polished glassy carbon electrode was very stable even afterapplying highly negative potentials. The electron transfer of potassium ferricyanide, catechol and dopamine at glassy carbon surfaces modified with thin (obtained by adsorption under controlled potential conditions) and thick (obtained by casting the glassy carbon surface with highly concentrated DNA solutions) DNA layers was slower than that at the bare glassy carbon electrode, although this effect was dependent on the thickness of the layer and was not charge selective. Raman experiments showed an impo