New nanoparticles make hidden chemical differences light up

Engineers at the University of Toronto have developed a new type of dye-sensitized nanoparticle that can detect chemicals at extremely low concentrations while also telling apart molecules that are nearly identical in shape.

The tiny particles produce a light signal after attaching to the chemical they are designed to detect. They absorb low-energy photons and convert that energy into higher-energy photons, creating a bright optical signal that researchers can measure.

That unusual ability could have practical uses in several fields. Pharmaceutical manufacturers, for example, could use the particles to identify unwanted impurities in drugs. Environmental researchers could potentially use them to search for very small amounts of chemical pollutants in groundwater.

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