Caltech Engineers Develop Smart Ingestible Capsule for Real-Time Gut Health Monitoring - Video

In a new advancement that could improve gastrointestinal diagnostics, a team of engineers at the California Institute of Technology (Caltech) has developed a smart ingestible capsule capable of detecting a variety of biomarkers inside the gut. Described in a new paper published in Nature Electronics, the capsule dubbed PillTrek offers a non-invasive and real-time method for analyzing metabolic and molecular information from the gastrointestinal (GI) tract.

Scientists have long sought reliable tools to monitor the wide range of biomarkers present in the complex GI environment. Traditional methods like fecal analysis or biopsy are invasive, costly, and limited in their ability to provide continuous, real-time data.

Developed by Professor Wei Gao and his team, PillTrek integrates a wireless electrochemical workstation within a capsule measuring just 7 millimeters in diameter and 25 millimeters in length smaller than current capsule endoscopy devices. “We designed this pill to be a very versatile platform,” said Gao, who is also a Heritage Medical Research Institute Investigator. “From an electrochemical-sensing point of view, it is very powerful. It has the ability to measure metabolites, ions, hormones such as serotonin and dopamine, possibly even proteins as well. And all within the gut, which is a complex environment.”

The proof-of-concept study demonstrated the capsule’s ability to measure pH, temperature, glucose, and serotonin levels in animal models. The capsule’s modular design allows for easy integration of various electrochemical sensors, which can be mass-produced using a previously developed 3D printing technique.

With its advanced sensing capabilities and small form factor, PillTrek represents a significant leap forward in real-time, in vivo diagnostics—potentially paving the way for personalized treatment and improved management of chronic gastrointestinal and metabolic conditions.

Reference: Min, J., Ahn, H., Lukas, H. et al. Continuous biochemical profiling of the gastrointestinal tract using an integrated smart capsule. Nat Electron (2025). https://doi.org/10.1038/s41928-025-01407-0