Micro and nanorobots (MNRs) hold great promise in healthcare—from mending life-threatening brain bleeds to precisely targeting tumors with chemotherapy. However, their clinical potential has been limited by challenges in navigating the complex environment of the human body.
At the University of Saskatchewan (USask), new research may finally help overcome these hurdles. USask College of Engineering professor Dr. Chris Zhang and his team—comprising PhD students Lujia Ding and N.N Hu, along with alumni Dr. Bing Zhang and Dr. R. Y. Yin—have developed a highly precise mathematical model that significantly improves the design and control of MNRs. This enhanced model enables the robots to maneuver efficiently through the bloodstream, a breakthrough that could pave the way for clinical trials. Their findings were recently published in Nature Communications.
Dr. Zhang explained, “The current models fail to fully account for the unique properties and dynamic behavior of blood in the human body. Our approach offers a more realistic depiction of blood vessel flow.” His motivation to improve MNRs began over a decade ago, following the experience of a former PhD student’s daughter who suffered a brain bleed. “At that time, the success rate with steerable catheters was only 25 per cent. This deeply motivated our team to pursue innovations that could potentially boost patient survival rates,” he added.
MNRs, which are corkscrew-shaped and guided by an external magnetic system, must generate enough power to swim against the flow of blood—comparable to a fish swimming upstream. Speed is critical in emergency medical situations, so the ability of these robots to move swiftly in challenging conditions is essential.
If these obstacles can be overcome, MNRs could access hard-to-reach areas, such as the tiny blood vessels in the brain or deep-seated tumors that are difficult to operate on. In these locations, the robots could either repair tissues, halt dangerous bleeding, or deliver medications like chemotherapy directly to the affected sites.
By offering new mathematical insights, Dr. Zhang and his colleagues have laid a foundation for the optimal design and control of these small yet powerful robots. In addition to their theoretical advancements, the team has also built an external power unit and created a prototype using 3D printing technology. Following promising prototype demonstrations, the next step is to advance to clinical trials—the critical final stage for the application of MNRs.
Dr. Zhang emphasizes the importance of cross-disciplinary collaboration in tackling complex challenges. “I thrive in cooperative environments, especially within healthcare. Although my background is in mechanical engineering, I am deeply involved in biomedical engineering and work closely with medical professionals. Different perspectives are crucial in research,” he noted.
