3D-printed 'microfish' swim in bloodstream to deliver drugs

New 3D-printed robots in the shape of small fish may one day be able to swim through bloodstreams, delivering drugs to the human body and removing toxins.

The "microfish" were created by a team of researchers at the University of California San Diego, who claimed they can print hundreds of the tiny robots in seconds.

According to the study, published in *Advanced Materials,*the robots measure just 120 microns long by 30 microns thick -- making them smaller than the width of a human hair. The microfish are made with platinum nanoparticles in their tails which, when they come into contact with hydrogen peroxide, causes their tails to move. Tiny iron oxide particles in their heads also allow the robot shoal to magnetically steer themselves.

The research showed the microfish could both sense toxins and work as detoxifying robots. Their bodies glowed a fluorescent red colour when placed in contaminated liquid as a result of toxic-neutralising particles reacting to the poison.

It's not just tiny fish bots that the team wants to put into action. The computer-aided design program used can also print 3D robotic rays and other sharks, and the researchers hope to experiment with bird-shaped bots in the future.

Jinxing Li, co-first author of the study, explained he hopes the microfish will lead the way in creating a new generation of "smartbots" that can help to pioneer new medical techniques. "Another exciting possibility we could explore is to encapsulate medicines inside the microfish and use them for directed drug delivery."

It could be a while before this robot bestiary becomes a reality. The synthetic microfish are still just a proof of concept, meaning they won't make it out of the laboratory and into the "wild" for some time yet.

This article was originally published by WIRED UK