The paper presents the thermodynamic analysis of adenine adsorption on a mercury electrode in an acetate buffer at pH 3 and pH 4. Adsorption energy and constants were determined using the Frumkin isotherm and the virial isotherm. Stronger adsorption in the buffer at pH 3 was observed in comparison to the buffer at pH 4. Using cyclic voltammetry and Faraday impedance measurement, an inhibitory effect of adenine on the kinetics of Zn (II) ion electro-reduction was observed.