Making sure the medicine goes down

Seeking a way to confirm that patients have taken their medication, University of Florida engineering researchers have added a tiny microchip and digestible antenna to a standard pill capsule.

The prototype is intended to pave the way for mass-produced pills that, when ingested, automatically alert doctors, relatives or scientists working with patients in clinical drug trials.

‘It is a way to monitor whether a patient is taking their medication in a timely manner,’ said Rizwan Bashirullah, UF assistant professor in electrical and computer engineering.

Bashirullah designed the prototype with doctoral student Hong Yu, University of Florida materials science and engineering professor Chris Batich, and Neil Euliano of Gainesville-based Convergent Engineering.

The pill itself is a white capsule coated with a label embossed with lines. The lines comprise the antenna, which is printed using ink made of nontoxic conductive silver nanoparticles. The pill also contains a tiny microchip, about the size of a full stop.

When a patient takes the pill, it communicates with a small electronic device carried or worn by the patient, which in the future could be built into a watch or cell phone. The device then signals a mobile phone or laptop that the pill has been ingested, in turn informing doctors or family members.

The pill needs no battery because the portable device sends it bursts of power that energise the microchip, causing it to send signals back via the antenna.

Eventually the patient’s stomach acid breaks down the antenna — the microchip is passed through the gastrointestinal tract — but not before the pill has confirmed its own ingestion.

The team has successfully tested the pill system in artificial human models, as well as cadavers. Researchers have also simulated stomach acids to break down the antenna to learn what traces it leaves behind.

Bashirullah said those tests had determined that the amount of silver retained in the body is tiny — less than what people often receive from common tap water.