Not unlike those fortune-telling fish you used to get at joke shops a new form of 3D-printed microfish – fish, not fiche – can wiggle and jiggle and wriggle inside you, dropping off medicine and cleaning up toxins as they go.
Researchers at the University of California, San Diego have created nano-sized fish out of materials that can react to their environment, allowing them to “swim” in various liquids. They also contain nanoparticles that can be used to inject chemicals into cells and organs. These are better than the traditional nano-scale robots in that they are actually shaped like swimming things.
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.
Obviously these fish are very primitive and will not taste good when placed, length-wise, on a delicious Caesar Salad. However they are an interesting use of nanotechnology and could be part of improved delivery systems for medicines. The fish can also clean up toxins in water. “As a proof-of-concept demonstration, the researchers incorporated toxin-neutralizing nanoparticles throughout the bodies of the microfish. Specifically, the researchers mixed in polydiacetylene (PDA) nanoparticles, which capture harmful pore-forming toxins such as the ones found in bee venom,” wrote the researchers. The swimming fish were able to grab and neutralize the toxins faster than normal chemical reactions thanks to their brisk swimming. I, for one, welcome our tiny fish-shaped robotic overlords.
