Researchers at Mass General Brigham and the University of Toronto have developed a swallowable biosensor pill called PRIM (Pill for ROS-responsive Inflammation Monitoring) that detects intestinal inflammation by releasing a visible blue dye in response to elevated levels of reactive oxygen species (ROS)—a chemical marker associated with inflammatory bowel diseases (IBD) like Crohn’s and ulcerative colitis.
The pill is coated with a ROS-sensitive polymer that remains stable under healthy conditions but breaks down when inflammation is present. Once the polymer degrades, the capsule releases Brilliant Blue FCF dye, which colors stool and toilet water, providing a clear, at-home visual signal without requiring stool handling or lab tests. In preclinical studies using rat models of colitis, the PRIM device correctly identified inflammation with 78% sensitivity and 72% specificity. It remained inactive in healthy rats, confirming its stability and selectivity.
Designed to be low-cost (estimated at $0.38 per unit), the PRIM pill could offer a noninvasive alternative to colonoscopies and fecal tests, which are often uncomfortable, expensive, or underused due to patient aversion. The team is now working to adapt the device for human use, including testing in larger animal models and refining its sensitivity to detect mild-to-moderate inflammation.
Article from Mass General Brigham: Mass General Brigham Researchers Develop Ingestible Biosensor Pill for At-Home Monitoring of Intestinal Inflammation
Abstract in Device: A radically simple, ingestible colorimetric biosensor pill for cost-effective, non-invasive monitoring of intestinal inflammation
