Solid state electrochemical cells are developed by using thin films of silver nanoparticles dispersed into polyethyleneimine. The material provides the ion conducting bridge between gold electrodes, thermally evaporated onto copier grade transparency sheet substrates, with one of the electrodes having on the top a layer of conducting ink based on multiwalled carbon nanotubes. The current-voltage loops of cells measured in water, are characterized by currents peaks that reversibly change their intensity in the presence of hydrogen peroxide.