The iPill navigates the digestive system by gauging pH levels, which it reads through onboard sensors. Acidity "is an excellent marker because the most important landmarks are when the pill leaves the stomach, and when it goes from the small intestine to the large intestine," says Philips senior scientist Jeff Shimizu.
"There's a very obvious pH jump." When the sensors detect a specified pH level that indicates arrival at the destination, the iPill begins dispensing medication-- which it can do all at once, in a series of bursts, or gradually.
As the iPill moves through the body, its wireless transmitter communicates information about both pH levels and temperature to an outside unit, providing doctors with internal information about the patient. "Based on the data that's coming out, you can adjust the behavior of the pill as it's en route," Shimizu says. "If, for example, there's an adverse reaction, you could stop the delivery of the medication instantly."
Philips, which is continuing testing of the prototype, hopes to move to clinical trials - and into an intestinal tract near you - soon.
