Electrode-electrolyte interface properties in implantation conditions.

A research was made on electrical properties of implantable electrodes. Materials used for this research were platinum (Pt), stainless steel (SS), gold (Au) and silver-silver chloride (Ag/AgCl) that was used as a reference electrode material although it is not suitable for implantation, Wetzig et al. The interface impedance of the electrode-electrolyte-interface in three different electrolytes, saline (0.9 m-% NaCl), SBF (simulated body fluid) and PBS (phosphate buffered saline), was measured. A Randies equivalent circuit was used to model the electrode-electrolyte-interface. The two independent components of the electric equivalent circuit of the interface were quantified for all materials in all electrolytes. Impedance of the electrode-electrolyte interface was measured by a slightly modified technique presented originally by Lario-Garcia et al.