A new surface based on poly(vinylferrocenium) (PVF+)-modified platinum electrode was developed for determination of Hg2+ ions in aqueous solutions. The polymer was electrodeposited on platinum electrode by constant potential electrolysis as PVF+ClO4- Cl- ions were then attached to the polymer matrix by anion exchange and the modified electrode was dipped into Hg2+ solution. Hg2+ was preconcentrated at the polymer matrix by adsorption and also complexation reaction with Cl-. Detection of Hg2+ was carried out by differential pulse anodic stripping voltammetry (DPASV) after reduction of Hg2+. Mercury ions as low as 5 x 10(-10) M could be detected with the prepared electrode and the relative standard deviation was calculated as 6.35% at 1 x 10(-6) M concentration (n = 6). interferences of Ag+, Pb2+ and Fe3+ ions were also studied at two different concentration ratios with respect to Hg2+. The developed electrode was applied to the determination of Hg2+ in water samples. (c) 2008 Elsevier B.V. All rights reserved.