“To create the microbots, we started by making polymer cubes that have a metallic coating on one side, essentially allowing the metallic side to act as a micro-magnet,” Koohee Han, first author of the study and Ph.D. candidate at NC State, told Digital Trends. “Depending on their position, the cubes can be assembled in many different ways. Once assembled, the microbots open when a magnetic field is applied and close when the field is removed. The orientation and gradient of the magnetic field allows us to control the rotation and movement of the microbots.”
Microbots aren’t a new development but the new study demonstrates progress in the field. Whereas previously reported versions had rigid bodies that restricted them to simple tasks like pushing and penetrating, the bots made by Han and his team have the ability to fold and change their shape like origami, enabling them to attach together, open, and close through magnetic stimulation.
In their study, the researchers tasked the microbots with capturing and transporting a live yeast cell, and controlled their movement by activating and deactivating the magnetic field.
“The ability to remotely control the dynamic reconfiguration of our microbot creates a new platform for exquisitely manipulating micro-scale objects such as single-cell isolation and targeted drug delivery,” said Wyatt Shields, co-author of the study and postdoctoral researcher at Duke University and NC State University. “Although this technology is still in its early stages, we believe these tools could one day entirely replace expensive and tedious micro-manipulators.”
The researchers point out that their current design is limited to 2D functions but they see their study as driving forward small, self-reconfigurable machines.
“We expect the principles of this simple platform can be extended to more advanced structures by using more advanced particle shapes, compositions, and field parameters to address a broad range of applications, from robotics and micro-manipulation to responsive materials and on-demand reconfigurable structures,” said Orlin Velev, corresponding author and professor of chemical and biomolecular Engineering at NC State.
A paper detailing the study was published this week in the journal Science Advances.
