Office of Technology Transfer – University of Michigan

Magnetically Switchable Particles

Technology #4856

Patchy particles have multiple functions

Patchy particles have multiple functions

Magnetically switchable particles

A method has been devised to engineer particles with magnetically activated surfaces. Researchers have demonstrated that it is possible to use a magnetic field to induce a change in color on a display made with these particles. Patchy poly(lactide-co-glycolide) particles are prepared such that one side of the particle is magnetic and dyed with carbon black, while the other side is non-magnetic and dyed yellow. When a magnet is placed near the particles, the magnetic end is attracted towards it and results in a black/dark blue display, and when the magnet is moved to the opposite end of the container, a yellow display is seen. This technology has enormous implications in the development of e-displays and smart materials.

Applications and Advantages


  • Black and white displays (e.g.: Kindle)
  • Smart glass
  • Magnetic drug delivery/diagnostics
  • Switchable catalysis


  • Allows precise switching of material properties