An electronic nose for the detection of alkylating agents
Written by Yair Gannot
Yair Gannota,b, Carmit Hertzog-Ronena, Yoav Eichena, Nir Tesslerb
aSchulich Faculty of Chemistry, bDepartment of Electrical Engineering, The Zisapel Nano-Electronics Center, Technion – Israel Institute of Technology, Technion City 32000, Haifa, Israel.
Alkylating agents (like alkyl-halides) are materials which have severe affects on human health, owing to their ability to react with many nucleophilic species in the body, and are unfortunately used, amongst other purposes, as chemical warfare agents. Detecting the presence of an alkylating agent in the atmosphere is thus an important need in modern society environment for early-warning purposes. Currently available sensing systems are, however, high-cost, cumbersome, and handled only by professional personnel.
Here we demonstrate the fabrication of an organic field-effect transistor (OFET) as an electronic sensor (E-nose) for the detection of alkylating agents in the atmosphere. Original pi-conjugated polymers were synthesized to serve as the active layer of the OFET sensor. These novel thiophene-pyridine-based polymers chemically react with various alkylating agents thus changing the device characteristics. The sensor is highly sensitive and is able to discriminate between alkylating agents and common volatile organic compounds like alcohols. The advantage of such an electronic-responsive device is the ability to easily fabricate a low-cost and small-size detector which could be used for wide spread deployment in public arenas and even as a disposable sensor for short term requirements.