A team of researchers from the University of Waterloo has developed smart, advanced materials that will serve as the foundation for future soft medical microrobots.
These microrobots have the potential to perform minimally invasive medical procedures such as biopsies, as well as transport cells and tissues. They can navigate through confined and fluid-filled environments, such as the human body, and deliver fragile cargo to specific locations.
These tiny soft robots are no more than one centimeter in length, and they are both biocompatible and non-toxic. They are composed of advanced hydrogel composites that incorporate sustainable cellulose nanoparticles derived from plants.
Under the leadership of Hamed Shahsavan, a professor in the Department of Chemical Engineering, this research demonstrates a comprehensive approach to the design, synthesis, fabrication, and manipulation of microrobots. The hydrogel used in this study undergoes shape changes when exposed to external chemical stimuli. The ability to control the orientation of cellulose nanoparticles allows researchers to program these shape changes, which is crucial for creating functional soft robots.
“In my research group, we are bridging the old and new,” said Shahsavan, who is also the director of the Smart Materials for Advanced Robotic Technologies (SMART-Lab). “We are introducing emerging microrobots by leveraging traditional soft matter such as hydrogels, liquid crystals, and colloids.”
Another unique feature of this advanced smart material is its self-healing capability, which enables a wide range of robot shapes to be programmed. Researchers can cut the material and reattach it without using adhesives, allowing for different shapes to be formed for various procedures.
The material can also be modified with magnetism to facilitate the movement of soft robots within the human body. As a proof of concept, researchers controlled the movement of a tiny robot through a maze using a magnetic field.
“Chemical engineers play a critical role in advancing medical microrobotics research,” Shahsavan stated. “Interestingly, addressing the numerous challenges in microrobotics requires the expertise and knowledge possessed by chemical engineers, including heat and mass transfer, fluid mechanics, reaction engineering, polymers, soft matter science, and biochemical systems. Therefore, we are uniquely positioned to introduce innovative avenues in this emerging field.”
The next step for this research is to downscale the robot to submillimeter sizes.
Shahsavan’s research group collaborated with Tizazu Mekonnen from the Department of Chemical Engineering at Waterloo, Shirley Tang (Associate Dean of Science, Research), and Amirreza Aghakhani from the University of Stuttgart in Germany.
