Ichiro Yamashita, Osaka University
Fabrication of device key nanostructures by protein supramolecules
Written by Mary Nora Dickson
Nature has developed exquisitely precise processes for the assembly of biomolecules into three-dimensional nanoarchitectures. Researcher Ichiro Yamashita of Osaka University has developed ways to combine natural bottom-up assemblies with traditional top-down fabrication for the manufacture of nanoscale functional materials, in a process he calls the “Bio-Nano-Process.”
For example, Yamashita utilized apoferritin protein-cages, found in nearly all cells, as a vessel for controlled cadmium sulfide infiltration and crystal growth. In this way, he was able to fabricate monodisperse 5 nm CdS nanocrystals. He utilized these nanocrystals for thermoelectric generation (the production of electric power from heat) by binding them to carbon nanotubes to form an electrically conductive but thermal nonconductive material. Another instance is Yamashita’s protein-templated growth of carbon nanotube forests for gas-sensing applications. There are myriad exciting applications for the Bio-Nano-Process, including solar energy generators, medical diagnostics, and sensors.