University of California at San Diego researchers have demonstrated a method to control and mix tiny amounts of liquids by encasing the chemicals in smart dust — silicon particles and magnetic nanoparticles.

A chemical coating causes the silicon particles to surround water droplets, and the dust changes color depending on the chemicals it is in contact with. This allows researchers to identify chemicals encased by the smart dust. The magnetic particles make it possible to move the particles — and the droplets they are surrounding — using a magnetic field.