A team of researchers that includes the University of Toronto's Caitlin Maikawa has developed a swallowable, low-cost device that allows people with inflammatory bowel diseases (IBD) to easily monitor their health at home.
The PRIM (Pill for ROS-responsive Inflammation Monitoring) device is designed to release a harmless blue dye in the presence of gut inflammation, changing the colour of stools and toilet water - an easy, at-home alternative to colonoscopies and lab-analyzed stool samples.
Described in a study published in the journal Device , the technology could help doctors and patients detect flare-ups earlier and adjust treatments more effectively.
IBD, which affects more than seven million people worldwide, is often marked by unpredictable episodes of inflammation in the digestive tract. While long-term management depends on curbing inflammation, current methods for monitoring gut health are either invasive, expensive or under-utilized. Colonoscopies are the gold standard but aren't practical enough for frequent use; stool tests are less invasive, but many patients are unwilling to collect and send samples, which limits long-term tracking.
"There's a clear need for a tool that can make routine inflammation monitoring easier and more accessible for patients," says Maikawa, an assistant professor at the Institute of Biomedical Engineering in U of T's Faculty of Applied Science & Engineering, who is co-leading the research alongside Yuhan Lee and Jeffrey Karp of Harvard Medical School and Brigham and Women's Hospital. "Our goal was to design something simple, affordable and patient-friendly that makes it possible to detect inflammation without needing a lab."
The PRIM device uses a chemical marker called reactive oxygen species (ROS), which increases in the intestines during inflammation. The pill is coated with a special polymer that remains intact in healthy conditions but breaks down when ROS levels are high. When this occurs, the pill releases a harmless blue dye.
If inflammation is present, the dye colours the stool and toilet water blue, providing a clear visual signal that can be observed at home without handling stool or using specialized equipment.
The team found that the pill detected gut inflammation in pre-clinical models with around 68 per cent accuracy. With its simple design and inexpensive materials, the device could cost less than 50 cents to manufacture at scale, the researchers estimate - making it more accessible to a broader population including those in lower-resource settings.
The researchers are now refining the pill's design to bring the technology closer to clinical use. Lucia Huang, co-lead author on the study and a master of science student in Maikawa's lab, is working on new polymer materials that will more sensitively detect inflammatory markers like ROS.
Future studies will also test the device in larger animal models that better mimic humans.
"We are working on refining the pill design, including improving the pill's accuracy and exploring how our pill could interface with digital health technologies," says Maikawa.
"Our long-term aim is to make regular inflammation monitoring as easy as possible."
