Smart Capsule to Target Colon Diseases

Based on reporting by Ben Gruber for Reuters.

Researchers at Purdue University in Indiana have engineered an electronic drug capsule that delivers medication directly to the colon — potentially a more effective and cheaper way to treat gastrointestinal conditions.

The capsule has two parts: one carries the drug payload, and the other houses electronics built on the same principles used to trigger a torpedo.

"There is a magnetic switch, and so when it gets close to the magnetic marker that can be worn outside the body or implanted close to where you want to release it, it will trigger the magnetic switch, discharge the capacitor, and you have a fuse that basically blows up," said lead researcher Babak Ziaie.

That reaction sets off a spring-loaded mechanism that splits the capsule and releases the medication — after an eight-hour journey through the stomach's harsh acidity and 20 feet of small intestine, with the drug payload reaching the colon intact.

The team designed the magnetic switch so that ordinary electromagnetic signals, such as those from cell phones, can't trigger the capsule. Whether the magnet is worn or implanted depends on the patient's weight.

"You have to be close — within a couple of centimeters. So for a lean person you can wear the magnet outside. But if someone is very obese, it actually won't trigger from outside, so you probably have to implant," Ziaie said.

The targeted delivery system could make drug treatment for gastrointestinal disorders — including bacterial infections, Crohn's disease, and Irritable Bowel Syndrome — more efficient and cheaper, according to Ziaie. He estimated the capsules could eventually be manufactured "for cents" once scaled up to commercial levels.

The team was working with a private biomedical company to start clinical trials.

More than 20 percent of people globally suffer from Irritable Bowel Syndrome, according to the International Foundation for Functional Gastrointestinal Disorders.