Free-Standing Gold-Nanoparticle Monolayer Film Fabricated by Protein Self-Assembly of [alpha]-Synuclein

Free-standing nanoparticle films are of great importance for developing future nano-electronic devices. We introduce a protein-based fabrication strategy of free-standing nanoparticle monolayer films. [alpha]-Synuclein, an amyloidogenic protein, was utilized to yield a tightly packed gold-nanoparticle monolayer film interconnected by protein [beta]-sheet interactions. Owing to the stable protein-protein interaction, the film was successfully expanded to a 4-inch diameter sheet, which has not been achieved with any other free-standing nanoparticle monolayers. The film was flexible in solution, so it formed a conformal contact, surrounding even microspheres. Additionally, the monolayer film was readily patterned at micrometer-scale and thus unprecedented double-component nanoparticle films were fabricated. Therefore, the free-floating gold-nanoparticle monolayer sheets with these properties could make the film useful for the development of bio-integrated nano-devices and high-performance sensors.