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nanotimes News in Brief
Professor John Boland, Director of CRANN, the Science Foundation Ireland (SFI) funded nanosci- ence institute at Trinity College Dublin, has been named the Laureate of the 2011 ACSIN Nanosci- ence Prize for his outstanding work in the develop- ment and application of scanning probe microscopy and spectroscopy and in the use of these tools to advance our understanding of chemical and physi- cal phenomena of materials.
11-09 :: September 2011
could generate proton currents to control certain functions directly.
A first step toward this type of control is a transistor that can send pulses of proton current. The proto- type device is a field-effect transistor, a basic type of transistor that includes a gate, a drain and a source terminal for the current. The UW prototype is the first such device to use protons. It measures about 5 microns wide, roughly a twentieth the width of a human hair.
Materials scientists at the University of Washing- ton (U.S.) have built a novel transistor that uses protons, creating a key piece for devices that can communicate directly with living things.
“So there’s always this issue, a challenge, at the interface – how does an electronic signal translate into an ionic signal, or vice versa?” said lead author Marco Rolandi, a UW assistant professor of materi- als science and engineering. “We found a biomate- rial that is very good at conducting protons, and al- lows the potential to interface with living systems.”
In the body, protons activate “on” and “off” swit- ches and are key players in biological energy trans- fer. Ions open and close channels in the cell memb- rane to pump things in and out of the cell. Animals including humans use ions to flex their muscles and transmit brain signals. A machine that was compa- tible with a living system in this way could, in the short term, monitor such processes. Someday it
“In our device large bioinspired molecules can move protons, and a proton current can be swit- ched on and off, in a way that’s completely ana- logous to an electronic current in any other field effect transistor,” Rolandi said.
The device uses a modified form of the compound chitosan originally extracted from squid pen, a structure that survives from when squids had shells. The material is compatible with living things, is easily manufactured, and can be recycled from crab shells and squid pen discarded by the food industry.
Chao Zhong, Yingxin Deng, Anita Fadavi Roudsari, Ad- nan Kapetanovic, M.P. Anantram, Marco Rolandi: A po- lysaccharide bioprotonic field-effect transistor, In: Nature Communications, Vol. 2(2011), September 2011, Article number: 476, DOI:10.1038/ncomms1489: http://dx.doi.org/10.1038/ncomms1489