Inflatable pill could offer long-term tracking of stomach conditions

31 January 2019 (Last Updated January 31st, 2019 12:47)

A team of engineers from the Massachusetts Institute of Technology (MIT) in the US has developed an ingestible pill that inflates in the stomach and monitors the organ’s temperature for up to a month.

Inflatable pill could offer long-term tracking of stomach conditions
The ingestible hydrogel device swells in water with high speed and a high ratio. Credit: Xinyue Liu.

A team of engineers from the Massachusetts Institute of Technology (MIT) in the US has developed an inflatable pill that swells in the stomach and monitors the organ’s temperature for up to a month.

To enable continuous tracking, a temperature sensor has been embedded into the pill.

The pill’s design is inspired by the defence mechanisms of the pufferfish (blowfish). It is made of mixtures of hydrogel polymers and water that contribute to its Jell-O-like consistency.

“The researchers also believe that insertion of tiny cameras will allow the pill to image the progress of tumours or ulcers over several weeks.”

According to the team, the combination allows swelling in the stomach and protects from the acidic environment.

The use of hydrogel is intended to make the device soft, biocompatible and long-lasting compared to existing ingestible sensors that can remain in the stomach for only days or are made of plastic or metal.

The pill can be removed by giving a patient a solution of calcium, which makes the device to shrink back to its original size and pass out safely from the body.

MIT mechanical engineering associate professor Xuanhe Zhao said: “The dream is to have a Jell-O-like smart pill that once swallowed stays in the stomach and monitors the patient’s health for a long time such as a month.”

The researchers tested the inflatable pill in a laboratory setting, where they immersed it in different water solutions and fluid similar to gastric juices. They observed that the pill swelled to 100 times its original size in approximately 15 minutes, which is considered faster than existing swellable hydrogels.

In order to assess the device’s toughness to withstand stomach churning, the team mechanically squeezed it numerous times and found the pill to be intact.

The researchers then inserted small, commercial temperature sensors into multiple pills and fed them to pigs. Analysis of the sensors’ temperature measurements demonstrated its ability to accurately monitor the animals’ daily activity patterns up to 30 days.

It is expected that the ingestible, inflatable pill will have a variety of medical applications, including the tracking of pH levels, or signs of certain bacteria or viruses in the stomach, based on the embedded sensor.

The researchers also believe that insertion of tiny cameras will allow the pill to image the progress of tumours or ulcers over several weeks.

They additionally said that the pill could potentially be used as an alternative to the gastric balloon, which is inserted into the stomach for weight loss.

In the UK alone, the overall cost of obesity to wider society is estimated at £27bn and is expected to reach £49.9bn by 2050.

Additional reporting by Charlotte Edwards.