ALBUQUERQUE, N.M., April 20 -- Intelligent nanostructures that report on their environment by changing color from blue to fluorescent red under mechanical, chemical, or thermal stress have been created by researchers at Sandia National Laboratories and the University of New Mexico. Most immediately, the self-assembling structures -- as durable as seashells -- may lower costs by reducing the need for expensive manufactured devices like stress detectors, chemical analyzers and thermometers, according to the press release from Sandia National Laboratories. "The material can distinguish between different solvents," said Sandia senior scientist and UNM professor Jeff Brinker. "There's a high correlation of color with the polarity of the solvent." The material also can report changes in mechanical stress and temperature. When the environmental disturbance is removed, the structures change back to their original color in some cases, making them potentially reusable. "The material is of interest to NASA -- one of the sponsors of our research -- for a thin film for an inflatable structure that would aid in the inhabitation of Mars," said Brinker. "The structure's skin would require a very thin yet strong membrane with low permeability that could sense mechanical damage from hazards such as meteorites or sandstorms." The color change of the coating would also be sensitive to the composition of chemicals hitting the structure's "skin," or to dangerous increases in temperature. The method, which involves a technique that links monomers into polymers in an orderly fashion within a nanostructure, is published this week in the April 19 issue of Nature.