University of Florida researchers have developed a signaling technology that can be embedded into drug tablets to notify clinicians and caretakers that a pill has been ingested. Although a bit of electronics is going to be moving through the digestive system, the researchers believe that it will pass safely without causing side effects to the patient. If the technology proves itself, we may soon be using it to confirm compliance in clinical trials or to monitor patients under a strict drug regimen.
One part is the pill, a standard white capsule coated with a label embossed with silvery lines. The lines comprise the antenna, which is printed using ink made of nontoxic, conductive silver nanoparticles. The pill also contains a tiny microchip, one about the size of a period.
When a patient takes the pill, it communicates with the second main element of the system: a small electronic device carried or worn by the patient – for now, a stand-alone device, but in the future perhaps built into a watch or cell phone. The device then signals a cell phone or laptop that the pill has been ingested, in turn informing doctors or family members.
Bashirullah [Rizwan Bashirullah, UF assistant professor in electrical and computer engineering] said the pill needs no battery because the device sends it power via imperceptible bursts of extremely low-voltage electricity. The bursts energize the microchip to send signals relayed 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 confirms 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 the amount of silver retained in the body is tiny, less than what people often receive from common tap water.