An innovative ingestible capsule, designed to measure gases inside the gut, has just passed phase one human trials. The swallowable sensor could reframe how gastrointestinal disorders are diagnosed, as well as offering a new insight into the activity of crucial bacteria in our gut microbiome.

The vast community of bacteria living inside our gastrointestinal system are constantly generating a variety of gases as they interact with unabsorbed bits of food. Hydrogen, carbon dioxide, nitrogen, and oxygen are all produced in various amounts and known to induce many unpleasant symptoms related to irritable bowel syndrome (IBS).

The ingestible sensor offers an entirely novel insight into our gastrointestinal system, with the research team discovering potentially new, previously unchronicled immune mechanisms.

"We found that the stomach releases oxidizing chemicals to break down and beat foreign compounds that are staying in the stomach for longer than usual," says Kourosh Kalantar-zadeh, capsule co-inventor and lead on the study. "This could represent a gastric protection system against foreign bodies. Such an immune mechanism has never been reported before."

Up until now it has proven notoriously difficult for doctors to accurately measure gut gas levels. Methods such as breath testing or tube insertion have been either uncomfortably invasive or frustratingly inaccurate. As well as giving doctors a picture of gas production inside the gut, this new sensor offers an entirely new way of analyzing the activity of our microbiome.

"Previously, we have had to rely on faecal samples or surgery to sample and analyse microbes in the gut," says Kalantar-zadeh. "But this meant measuring them when they are not a true reflection of the gut microbiota at that time. Our capsule will offer a non-invasive method to measure microbiome activity."

The first human trials showed the capsules to have no negative health effects and easily passed through the systems of all subjects RMIT

The latest study, conducted at RMIT and Monash University in Australia, reveals successful phase one human trials showing the capsule sensors to be safe and effective in all human subjects. Early results are delivering compelling new insights into our digestive activity including a previously undiscovered observation of oxygen in our colon.

"Trials showed the presence of high concentrations of oxygen in the colon under an extremely high-fibre diet," says Kalantar-zadeh. "This contradicts the old belief that the colon is always oxygen free. This new information could help us better understand how debilitating diseases like colon cancer occur."

The researchers are currently raising funds to bring the research into phase two of the human trials ahead of the capsule finally getting into the hands of doctors and the stomachs of patients.

The study was published in the journal Nature Electronics.

Source: RMIT