Scientists at the University of Washington (USA) have developed a new type of transistor that uses protons instead of electrons for charge transport. It is intended to simplify the interfacing of electronic circuitry to the brains of living organisms, since protons (positively charged hydrogen atoms) and ions are responsible for signal transport between nerve cells. Proton-based transistors are therefore better suited to controlling and monitoring processes in the brain.
The researches discovered that the natural biomaterial chitosan, obtained from squid pens and crab shells, is a good proton conductor. They then used it to fabricate a transistor that can generate proton pulses. The prototype device is a field-effect transistor with a source, gate and drain, but it operates with protons.
The proton current can be switched on and off in the same way as the electron current in a conventional FET. The current prototype is built on a silicon substrate and is therefore not suitable for direct implantation in the body, but the researchers expect that a biocompatible version suitable for direct control of biological processes will be developed in the future.
The results of the research were published recently in Nature Communications.
Image: Marco Rolandi, UW