An electrochemical sensor of non-electroactive drug 6-thioguanine based on the dsDNA/AET/Au

Surface electrochemical method based on dsDNA film modified electrode is applied to a preliminary screening of anticancer drug 6-thioguanine (6-TG). A composite film containing dsDNA was fabricated on 2-aminoethanethiol self-assembled monolayers film modified gold electrode (AET/Au SAMs) by electrostatic adsorption. The two electrochemical probes of [Fe(CN)(6)](3-/4-) and Co(bPY)(3)(2+/3+) were used to investigate the interaction between dsDNA and 6-TG, Fluorimetry and UV-vis spectrometry proved further the interaction. The peak currents of the electrochemical probes were linear with the concentrations of 6-TG, a high sensitivity and a low detection limit was obtained, this modified electrode can be used to determine the concentration of 6-TG. (c) 2006 Published by Elsevier B.V.