"Biological Path to Nanodevices - Biological Nano-Fabrication of Devices by Protein Supramolecules ?"
Who: Ichiro Yamashita, Osaka University, Japan
Place: nanoGUNE seminar room, Tolosa Hiribidea 76, Donostia - San Sebastian
Date: Monday, 9 October 2017, 11:00
We have been proposing a biological process to fabricate nanodevices by protein supramolecules, which we named ?Bio Nano Process? (BNP)1,2).
In the BNP, protein supramolecules work as templates for the biomineralization of homogenous nanoparticles (NPs) and nanowires (NWs). Artificial biomineralization covers a wide variety of inorganic materials from conventional bio-related materials to naodevice-related inorganic materials. We have been expanding the proteins? biomineralization capabilities by genetic modification, and now can synthesize NPs and NWs of metal-complex and/or semiconductor materials3).
The surfaces of protein supramolecules are further modified chemically or genetically to make them self-organize to functional nano-structures at designated positions of the substrates. One typical example is a two dimensional crystalline array of cage-shaped proteins, ferritins, with 7nm NP4). The array were used as charge-storage nodes in the floating gate memory.
Another type of functional nanostructure is a hetero-junction by small cage shaped protein, Dps. The Dps is modified to have abilities to bind CNT and biomineralize 4nm semiconductor NP inside. The hetero-junctions, CNT/Dps(semiconductor NP)/CNT, are self-constructed by mixing them in aqueous solution. The junctions show new types of Seebeck-effect, p- and n-type thermoelectric materials are obtained5).
Besides them, we have designed and produced several kinds of protein supramolecules for the BNP and applied them to produce key components of nanodevices, such as a floating nanodot gate memory (FNGM), a single electron transistor, a Re-RAM, quantum solar cell, bio-sensors, Single Nucleotide Polymorphism (SNP) sensing LoC, dyes-sensitized solar cell, thermo-electronic device, and other electronic devices 6-8).
The processes are carried out in the aqueous condition under room temperature. No toxic organic solvents are necessary, which means that the BNP is intrinsically eco-friendly. Keywords: Bio-nano-Process, Self-Assembly, Biomineralization, Peptide aptamer
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Host: M. Okuda / A.M. Bittner