Aqueous suspensions of micrometer-sized latex particles coated with poly(vinylferrocene) showed voltammetric responses of poly(vinylferrocene) at the nitrobenzene(NB)-coated pyrolytic graphite electrode (PGE), although these were electroinactive at conventional metal electrodes. The whole process consists of diffusion of the latex particles in the water phase, dissolution of the particles in the NB film, the electrode reaction of dissolved poly(vinylferrocene), and the partition of poly(vinylferrocene) to the aqueous phase. The rate-determining process was in the dissolution kinetics, and hence the voltammogram showed surface waves of poly(vinylferrocene) immobilized on the NB film. The amount of the redox charge increased with time of the immersion of the PGE into the suspension. The latex particles were synthesized with copolymerization of styrene and vinylferrocene on polystyrene latex particles. One latex particle contains 2.1 x 10(7) ferrocene moieties in the overlayer of the core polystyrene. (C) 2003 Elsevier Science B.V. All rights reserved.