Molecular-scale biophotodiode consisting of a green fluorescent protein/cytochrome c self-assembled heterolayer

摘要

A molecular photodiode that consists of a protein heterolayer is investigated at the molecular scale for construction of a bioelectronic device. Cytochrome c and green fluorescent protein (GFP) were used as an electron acceptor and a sensitizer in the molecular layer by mimicking photosynthesis. A self-assembled monolayer of thiol-modified cytochrome c was formed on Au-coated glass, and then GFP was adsorbed onto the cytochrome c surface by electrostatic attraction. Photoinduced current was generated and the photoswitching property was observed by repeated step illumination. The rectifying property by scanning tunneling spectroscopy based current-voltage characteristics was achieved in the protein heterolayer. Thus, the proposed heterolayer functioned as a biomolecular photodiode with photocurrent generation and the rectifying property.