Engineers at the University of Colorado Boulder have developed a groundbreaking class of small, self-propelled robots that can swiftly navigate through liquids, potentially delivering medication to inaccessible areas within the human body. Published in the journal Small, the research paper details these miniature healthcare providers. Lead author Jin Lee envisions a future where these microrobots can perform non-invasive surgeries by simply introducing them into the body via a pill or injection.
Although this goal has not been achieved yet, the team's work marks significant progress. Measuring just 20 micrometers wide, the microrobots can reach speeds of 3 millimeters per second, making them much faster than a cheetah relative to their size. In a promising experiment, the robots successfully transported doses of dexamethasone, a common steroid, to the bladders of lab mice, indicating their potential in treating bladder diseases and other ailments. Assistant professor C. Wyatt Shields highlights the unique aspect of these microscale robots being designed to perform useful tasks within the body.
Its Challenging!!!
This scenario may seem like it was taken straight out of a science fiction story, and that's because it was. The 1966 film Fantastic Voyage depicted a group of explorers entering a man's body using a shrunken submarine. However, today's reality is catching up with that imagination, with the advent of micrometer- and nanometer-scale robots. Lead researcher Jin Lee envisions these microrobots swimming through a person's bloodstream, targeting specific areas for treatment.
The team manufactures these robots using biocompatible polymers, employing a technology similar to 3D printing. Resembling miniature rockets with three fins, the robots possess a unique feature: each carries a trapped air bubble, which, when exposed to an acoustic field like ultrasound, vibrates vigorously, propelling the robots forward by pushing water away. Other co-authors from CU Boulder include Nick Bottenus, Ankur Gupta, and graduate students Ritu Raj, Cooper Thome, Nicole Day, and Payton Martinez. In their research, the team focused on using the microrobots to address bladder disease, serving as a test case for their capabilities.
Providing An Alternative Solution
Millions of Americans suffer from interstitial cystitis, also known as painful bladder syndrome, which causes intense pelvic pain. The treatment for this condition often involves multiple clinic visits over several weeks, where a doctor administers dexamethasone through a catheter, leading to patient discomfort. Jin Lee believes that microrobots could offer a potential solution. In laboratory experiments, the researchers developed microrobots containing high concentrations of dexamethasone and introduced them into the bladders of lab mice.
The microrobots dispersed throughout the organs and adhered to the bladder walls, providing a sustained release of dexamethasone over approximately two days. This continuous drug delivery could improve patient outcomes by allowing for a longer duration of medication. Lee acknowledges that there is still significant work to be done before microrobots can navigate human bodies, such as ensuring complete biodegradability. The goal is to achieve sustained drug release in the bladder, reducing the frequency of clinic visits for patients.
Source:
Materials provided by University of Colorado at Boulder. Original written by Daniel Strain. Note: Content may be edited for style and length.
Journal Reference
Jin Gyun Lee, Ritu R. Raj, Cooper P. Thome, Nicole B. Day, Payton Martinez, Nick Bottenus, Ankur Gupta, C. Wyatt Shields. Bubble‐Based Microrobots with Rapid Circular Motions for Epithelial Pinning and Drug Delivery. Small, 2023; DOI: 10.1002/smll.202300409