Many orally ingested medicines are limited in their applications because they get absorbed or metabolized by the body before arriving at their final destination, the large intestine being a perfect example of such a destination. Researchers at Purdue University have developed an electronic pill, about the size of a large gel cap that can travel through the GI tract and release its cargo once it’s far enough. The device doesn’t propel itself, rather riding along with peristalsis.
The release of the powdered drug cargo is enabled by a pre-charged capacitor and the opening of the chamber is activated using a magnet. In laboratory experiments, a magnet placed nearby the channel simulating the GI tract was used to open the drug chamber, but the researchers believe that in the future a wrist-worn magnet may end up being used since the hands are near the level of the large intestine when at rest.
Watch the capsule travel through a simulated GI tract and release its cargo (you might want to fast forward through the slow parts):
Study in IEEE Transactions on Biomedical Engineering: A smart capsule with GI-tract-location-specific payload release
Source: Purdue University