Modified electrodes were obtained from pyrrole and aniline on different substrates like: platinum, titanium, zinc or aluminium substrates by electropolymerization or by co-electropolymerization from synthesis solutions containing different ratio of monomers. Cyclic voltammetry and electrochemical impedance spectroscopy were used to investigate the electrochemical properties of the resulting modified electrodes. Further, an amperometric biosensor for glucose was prepared by immobilization of glucose-oxidase into a poly(o-phenylenediamine) film by simple one-step electropolymerization on platinum substrate. The rejection of interference species may be additionally increased by placing additional layers of Prussian Blue that ensured electrode operation at low potential values or of polypyrrole, respectively.