3D-printed
microfish contain functional nanoparticles that enable them to be
self-propelled,
chemically powered and magnetically steered. The microfish
are also capable
of removing and sensing toxins.
Image credit: J.
Warner, UC San Diego Jacobs School of Engineering.
(August 25, 2015) Researchers
demonstrate a novel method to build microscopic robots with complex shapes and
functionalities.
Nanoengineers at the University of California, San Diego
used an innovative 3D printing technology they developed to manufacture
multipurpose fish-shaped microrobots — called microfish — that swim around
efficiently in liquids, are chemically powered by hydrogen peroxide and
magnetically controlled. These proof-of-concept synthetic microfish will inspire
a new generation of “smart” microrobots that have diverse capabilities such as
detoxification, sensing and directed drug delivery, researchers said.
The technique used to fabricate the microfish provides
numerous improvements over other methods traditionally employed to create
microrobots with various locomotion mechanisms, such as microjet engines,
microdrillers and microrockets. Most of these microrobots are incapable of
performing more sophisticated tasks because they feature simple designs — such
as spherical or cylindrical structures — and are made of homogeneous inorganic
materials. In this new study, researchers demonstrated a simple way to create
more complex microrobots.
Schematic
illustration of the process of functionalizing the microfish.
Platinum
nanoparticles are first loaded into the tail of the fish for propulsion
via reaction with
hydrogen peroxide. Next, iron oxide nanoparticles are
loaded into the
head of the fish for magnetic control.
Image credit: W.
Zhu and J. Li, UC San Diego Jacobs School of Engineering.
The research, led by Professors Shaochen Chen and Joseph
Wang of the NanoEngineering Department at the UC San Diego, was published in
the Aug. 12 issue of the journal Advanced Materials.
By combining Chen’s 3D printing technology with Wang’s
expertise in microrobots, the team was able to custom-build microfish that can
do more than simply swim around when placed in a solution containing hydrogen
peroxide. Nanoengineers were able to easily add functional nanoparticles into
certain parts of the microfish bodies. They installed platinum nanoparticles in
the tails, which react with hydrogen peroxide to propel the microfish forward,
and magnetic iron oxide nanoparticles in the heads, which allowed them to be
steered with magnets.
Fluorescent image
demonstrating the detoxification capability
of the microfish
containing PDA nanoparticles.
Image credit: W.
Zhu and J. Li, UC San Diego Jacobs School of Engineering.
“We have developed an entirely new method to engineer
nature-inspired microscopic swimmers that have complex geometric structures and
are smaller than the width of a human hair. With this method, we can easily
integrate different functions inside these tiny robotic swimmers for a broad
spectrum of applications,” said the co-first author Wei Zhu, a nanoengineering
Ph.D. student in Chen’s research group at the Jacobs School of Engineering at
UC San Diego.