MIT researchers pose with prototypes of their smart pill and a vial of the engineered bacteria key to the work. (Credit: MIT)

A smart pill the size of a blueberry could be a game changer in the diagnosis and treatment of bowel diseases. That’s because it is the first technology compatible with ingestion that can automatically detect — and report on in real time — key biological molecules that could be indicative of a problem.

The new pill, which has been successfully tested in pigs, combines specially engineered living bacteria with electronics and a tiny battery. When the bacteria sense a molecule of interest, they produce light (the bacteria by themselves have also been successfully tested outside of animals and in mice). The pill electronics then convert that light into a wireless signal that can be transmitted through the body to a smartphone or other computer in real time as the pill travels through the gut.

The researchers showed that the smart pill could detect nitric oxide, a short-lived molecule that is associated with many inflammatory bowel diseases. Importantly, the sensors could also detect different concentrations of nitric oxide.