Delivering drugs to a specific internal organ often affects other organs along the way, causing side-effects and reducing the amount of medication that reaches the target area. To address this issue, researchers at Purdue University have designed a tiny robot that does back-flips through the colon to deliver medicine.
Organs like the colon have a wild internal environment. Rough terrain and constantly moving fluids and solids make the colon particularly tricky for a robot to travel through. So instead of designing a complex robot, the research team focused on locomotion. A robot that does backflips rotates like a car tire does to adjust for an off-road ride.
Smaller than a single letter printed on a penny, the rectangular robot tumbles easily through the colon of live mice. The researchers used an external, rotating magnetic field to provide the robot with wireless power and to control its movements. They can monitor its journey with standard ultrasound imaging.
For the current studies of mice, the robot carried a tiny vial of saline solution, and gradually released the payload over one hour. Researchers believe the robot could be directed to a specific site within the colon, and then remain stationary during the release of the medication.
Treating humans or larger animals could require an army of dozens of robots. Non-toxic and biocompatible, each robot can carry its own drug payload, which could facilitate multi-area targeting. They’re made of readily-available polymer and metal materials and can be fabricated using a standard machine manufacturing process. Mass-production is cheap and easy.
The research team sees potential for using the robots as a diagnostic tool, such as a simpler (and much more comfortable) alternative to a colonoscopy. The team published their findings in the journal Micromachines earlier this year.
