Stanford Researchers Create Self-propelled Medical Implant
You may have noticed a running theme with many of the posts here on Engineering on the Edge. It is science fiction made science fact. I don’t know how many sci-fi movies, TV shows and books I’ve seen in which a doctor can solve all manner of ills with a simple hypodermic injector. In go nanobots or tiny medical implants and Presto! the patient is good as new.
The problem with real, functional medical tech that could produce results inside the human body is how to power them. While science has made astonishing strides in miniaturization over the years, methods to power these devices has lagged behind. In most cases, the battery required to power the tiniest devices takes up around half of the machine.
While we have gotten very good at shrinking electronic and mechanical components of implants, energy storage has lagged in the move to miniaturize. This hinders us in where we can place implants within the body and also creates the risk of corrosion or broken wires, not to mention replacing aging batteries.
— Teresa Meng, Stanford professor of electrical engineering and computer science
A team of researchers at Stanford believes they have solved the problem of how to power a medical device that has been implanted into a human body without relying on cumbersome batteries. Led by Ada Poon, assistant professor of electrical engineering, the team has created a device that, put in the simplest terms, is powered by radio waves.
Once the problem of how to power the implant was solved, Poon and her team created two prototypes. The devices measure 3mm x 4mm, which is small enough to travel through the blood stream. One device pushes electrical current through the bloodstream to propel itself forward. The other device goes with the flow, so to speak, and uses back-and-forth movement similar to how a kayaker might paddle.
There is considerable room for improvement and much work remains before such devices are ready for medical applications. But for the first time in decades the possibility seems closer than ever.
—Ada Poon, Stanford assistant professor of electrical engineering
Poon is now working with medical experts to develop applications for the breakthrough. Possible uses include using the implants to deliver drugs, perform diagnostics and perhaps minimally invasive surgery.
Below you’ll find a video that shows how the implants operate.