Wang is also working with UC San Diego
nanoengineering professor Shaochen Chen,
an innovator in 3-D printing technology, to
develop “microfish”—microscopic fish-shaped
robots. Similar to Wang’s tubular micromotors, these microfish swim via a chemically
powered reaction, yet can also be steered
with magnets. “We incorporated a traditional
micromotor into a nature-inspired design,
such as a fish shape, to create a ‘smart mi-croswimmer’ that can do multiple tasks in
solution,” says Chen.
By combining Wang’s expertise in micromachines and Chen’s 3-D printing technology,
researchers were able to print hundreds of
multitasking microfish within seconds. The
microfish were printed with tiny pieces of platinum in their tails, which react with hydrogen
peroxide to serve as external fuel. When the
fish then were released in a hydrogen peroxide
solution, the tails produced a stream of oxygen
bubbles as propellant, while tiny magnetic
iron oxide particles printed into the heads of
the fish allowed researchers to guide the fish
Researchers also printed unique nanoparticles throughout the bodies of the microfish
to detect and absorb poisonous toxins. In their
experiments, researchers showed that the
microfish could efficiently detoxify a solution
contaminated with a poison found in bee venom.
When the nanoparticles bind with toxin molecules, they even glow red in color, making the
fish also useful as toxin sensors.
The versatility of these microfish may
hold great potential in and out of the body,
but they are still at the proof of concept stage.
Wang and Chen forecast several years before
they can be used for medical applications. As a
step toware this goal, researchers are planning
to build microfish that are powered by more in
vivo-friendly fuels, such as water or enzymes.
Nanoengineering professor Shaochen Chen, a leader
in 3-D printing, uses nature-inspired design to create
tiny microfish that can be steered with magnets.