Gas-sensing pill promises to revolutionise gastric treatment
Swallowable capsules that detect levels of different gases in the gut and send results to a mobile phone are set to be commercialised following the first tests on humans in Australia.
Researchers at RMIT University in Melbourne and colleagues at Monash University believe the pill-sized ingestible devices, which measure hydrogen, carbon dioxide and oxygen and send results to a mobile phone, will be a game-changer for the one-in-five people worldwide who will suffer from a gastrointestinal disorder in their lifetime. They could also reduce the need for invasive procedures like colonoscopies.
Professor Kourosh Kalantar-zadeh, a co-inventor of the device who led the tests, believes the results reported in Nature Electronics could improve understanding of how debilitating diseases like colon cancer occur. They also demonstrated that the capsule could offer a much more effective way of measuring microbiome activities in the stomach, a critical way of determining gut health, he added.
"Previously, we have had to rely on faecal samples or surgery to sample and analyse microbes in the gut. 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."
Each capsule’s electronic components are housed in an opaque polyethylene shell 26mm long and 9.8 mm in diameter. They include gas sensors capable of operating in both aerobic and anaerobic conditions, a temperature sensor, a microcontroller, a 433MHz transmission system and a button-size silver oxide battery.
Information about temperature and the concentration of the gases being monitored is continuously transmitted from the capsule to a monitor that uses a Bluetooth connection to display profiles in real time on a mobile phone.
The temperature sensor and transmission circuit require a low enough current to be able to operate for nearly 30 days, which means devices can be tracked for their entire journey through the body and retrieved once excreted. Future versions might be able to run even longer by harvesting energy from the liquid of the gut. Gas sensing requires more energy, but is extended to four days by including a microcontroller that puts the electronic components inside the capsule to sleep mode when not in use.
According to co-inventor Dr Kyle Berean, ingestible sensors offer a potential diagnostic tool for many disorders of the gut from food nutrient malabsorption to colon cancer. “It is good news that a less invasive procedure will now be an option for so many people in the future,” he commented.
The project also uncovered previously unseen mechanisms in the human body, including a potentially new immune system. The trials found evidence that the human stomach uses an oxidiser to fight foreign bodies that stay in the gut for longer than usual, an immune response that has never been reported before. Another never before seen observation was the presence of high concentrations of oxygen in the colon under an extremely high-fibre diet, contradicting the belief that the colon is always oxygen free.
Now that the capsule has successfully passed human trials, the research team has partnered with Planet Innovation to establish a new company, Atmo Biosciences, which will commercialise the technology and bring a product to market.