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.