The newly developed DNA-biosensor is a very promising tool for the inv
estigation and study of the action of drugs specifically designed to i
nteract with DNA. In this work the electrochemical reduction of nitroi
midazole drugs was studied in the presence of DNA immobilized onto the
surface of a glassy carbon electrode. This enabled preconcentration o
f the drug onto the electrode surface, which was then electrochemicall
y reduced to the corresponding hydroxylamine which followed by reoxida
tion give the nitroso compound and subsequently an azoxycompound. More
over, as the target of the nitroimidazole action was the DNA, the dama
ge caused to DNA on the electrode surface by a reduction product of th
is drug could be detected in situ.