PE film was treated with fuming nitric acid at 80℃ for 20 min, resulting in introduction of COOH moieties on the film surface. The COOH’s were reacted with ethylenediamine,
whose amino groups were used for linking with (2-[4-(dibutylamino)phenyl]ethenyl)-3-carboxy-methylbenzo-thiazolium, photoelectric dye (NK-5962), which absorbs visible light and converts the photon energy to electric potentials. The dye molecules were immobilized
on the PE film surface and they were able to stimulate chick retinal tissues on incidence of visible light. These facts hopefully lead to development of an artificial retinal prosthesis