MULTITASKING MICROFISH
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 microswimmer ’ 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 with magnets .
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 .
MICROFISH MAKER Nanoengineering professor Shaochen Chen , a leader in 3-D printing , uses nature-inspired design to create tiny microfish that can be steered with magnets .
24 TRITON | WINTER 2016