The bots were specifically modeled after the genus of unicellular ciliated protozoans known as Paramecia. Cilia are the hair-like organelles protruding from the bodies of the paramecia. Their whiplash movement propel the protozoans.
Researchers at Daegu Gyeongbuk Institute of Science and Technology modeled the movements of cilia to create a microbot uniquely positioned to navigate viscous fluid environments inside the human body.
The ciliary strokes are made possible by hair-like microstructures controlled by what’s called asymmetric magnetic drive technology. The tiny bots feature a core made of a photo-curable polymer material, surrounded by layers of nickel and titanium. A laser was used to carve out the cilia.
Previous fluid-navigating bots have utilized different motions powered by magnetic attraction. The new microbots trigger the whip-like motion of their cilia via magnetic actuation, yielding faster, more efficient movements. In other words, magnetic fields don’t pull a bot in a specific direction but trigger a series of motions to propel it forward.
“With precise three-dimensional fabrication techniques and magnetic control technology, my team has developed microrobots mimicking cilia’s asymmetric reciprocation movement, which has been never realized so far,” Choi Hong-soo, a professor of robotics engineering at DGIST, said in a news release. “We’ll continually strive to study and experiment on microrobots that can efficiently move and operate in the human body, so that they can be utilized in chemical and cell delivery as well as in non-invasive surgery.”
Scientists detailed the microbots’ unique technology and biomedical promise in the journal Scientific Reports.