CHEMSENSING :: INK NOSE

A sensor that detects odors better than the human nose may be able to smell dangerous air pollutants, soil contaminants, insecticides, food pathogens, biological warfare neurotoxins, and body odors associated with illness and disease. At the University of Illinois at Urbana-Champaign, chemistry professor Kenneth S. Suslick and graduate student Neal A. Rakow have spent four years developing a sensor that sniffs out odors by "seeing" them. Called "smell-seeing" by its inventors, the method relies on color changes that occur in an array of vapor-sensitive dyes in response to exposure. This newest version of an artificial nose is simple, fast, and inexpensive.
The ink on this paper changes color when exposed to odor. In the future it could be used on a milk container to detect spoilage.

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