DNA-modified electrodes - Part 3: spectroscopic characterization of DNA-modified gold electrodes

DNA-modified gold electrodes were characterized by scanning tunneling micro scopy (STM), Raman spectroscopy, in situ UV/Vis reflection spectroscopy, X- ray photoelectron spectroscopy (XPS) and alternating current (AC) impedance . It has been found that dsDNA adsorbed firmly on gold surfaces lies strand -on in an ordered saturated monolayer, and ssDNA strands exist in a honeyco mb-like form on the surfaces. The bases and phosphate groups of DNA backbon e interacting with gold electrode surfaces play an important role in DNA im mobilization onto gold electrode surfaces. (C) 1999 Elsevier Science B.V. A ll rights reserved.