Liquid crystals serve as foundation for new chemical sensors
The behavior of liquid crystals provides the foundation for highly sensitive, very small, real-time and potentially wearable chemical sensors. John T. and Magdalen L. Sobota Professor of Chemical and Biological Engineering Nicholas Abbott and co-author Rahul R. Shah describe the device in the August 17 issue of Science magazine.
The sensors could be used to measure personal exposure to chemicals in variety of environments including pesticides and chemical warfare agents. In flat panel displays, electric fields change the orientation of liquid crystals to produce different optical appearances. Abbott's sensors also take advantage of this shift in orientation but do not require electrical input.
Abbott's group engineered surfaces that change the orientation and appearance of liquid crystals when different chemicals bind to the surface. The research team has demonstrated the device's sensitivity to both amine and organophosphorus compounds.
The BBC World Service program Science in Action recently featured Abbott's work. The report can be found at http://www.engr.wisc.edu/cgi/bin/forward/http://www.bbc.co.uk/worldservice/programmes/sci_act.shtml