Ingestible electronic capsules that can sense different gases in the gut, and can distinguish changes in a person’s diet, are reported in a paper published online this week in Nature Electronics. The devices could potentially be used to help understand the effects of diet and medical supplements, and to help develop individualized diets.

Ingestible sensors are an emerging technology that could play a powerful role in the monitoring of human health, but the capabilities of the devices are currently relatively limited.

Kourosh Kalantar-Zadeh and colleagues have developed small ingestible capsules that contain gas sensors, a temperature sensor, a small computer (microcontroller), a radio-frequency transmitter, and batteries. In a small human pilot trial (six healthy volunteers), the sensors are shown to be capable of sensing oxygen, hydrogen, and carbon dioxide as the device travels the length of the gut, transmitting the gas concentration data to a pocket-sized receiver carried by the volunteers. The gas concentration profiles reflect, in particular, the gases produced by the microbial community of the gut during food fermentation and could be used to distinguish volunteers on high- and low-fibre diets.

The results also highlighted that the electronic capsules are capable of detecting the different fermentation patterns of individuals, which suggests that the sensors could be used to monitor a person’s response to a custom diet.