Chemical sensors gain true portability
In a step toward warning badges for military personnel and spoilage indicators for supermarket items, researchers have created novel films that change color on contact with selected chemicals, such as those found in nerve gas or rotting fish.
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Scientists have already devised a variety of sensors for specific chemicals (SN: 2/19/00, p. 125), but such technology generally requires lasers, spectrometers, power sources, and other large, complicated devices to read out its messages. The new sensors, however, are simpler–flat films that require no electronic parts and that visibly change in color or shading to warn of troublesome molecules in the air.