The influence of photoelectron processes in a semiconductor substrate on the adsorption of polycationic and polyanionic molecules

Abstract

White-light illumination during the adsorption of polyanionic molecules of glucose oxidase (GO_x) enzyme on the surface of p-Si/SiO₂/polyethylenimine structure leads to a threefold decrease in the surface concentration of GO_x molecules. Same illumination during the GO_x adsorption on the n-Si/SiO₂/PEI structure leads to a sevenfold increase in the surface concentration of enzyme molecules. Changes in the amount of adsorbed GO_x molecules depending on the intensity of irradiation are explained by electron transfer processes and recharging of electronic states at the Si/SiO₂ interface and within SiO₂ layer.