Comparative analysis of the charge transfer processes of the Ru(NH3)63+/Ru(NH3)62+ and Fe(CN)63−/Fe(CN)64− redox couples on glassy carbon electrodes modified by different lipid layers

Langmuir–Blodgett lipid films deposited onto glassy carbon electrodes were analyzed by comparing the voltammetric profiles of the Ru(NH3)63+/Ru(NH3)62+ and Fe(CN)63−/Fe(CN)64− redox couples. The responses were correlated with the behavior of the lipid monolayers at the air ∣ water interface giving the same tendency in the compressibility factors as in the electrochemical blocking effect. Digital simulation of some current–potential profiles was successfully done in the case of the Ru(NH3)63+/Ru(NH3)62+ couple, which proved to be a better marker ion as it does not have the well known drawbacks of the Fe(CN)63−/Fe(CN)64− couple. A model which considers the effect of macroscopic inhomogeneities of the surface on the electrochemical response was used.