The ingestible sensor developed by MIT. Image: Lillie Paquette/MIT
In the near future, digestion issues may be diagnosed in real time just by swallowing this powerful smart pill.
Anyone presenting themselves to a doctor with stomach problems will likely be familiar with the not-so-pleasant and intrusive testing that needs to be done in many cases – but what if there was a much simpler way?
This is now a distinct possibility thanks to a breakthrough achieved by a team from MIT. It has unveiled an ingestible sensor pill equipped with genetically engineered bacteria, capable of diagnosing bleeding in the stomach or other gastrointestinal problems.
Taking the ‘bacteria-on-a-chip’ approach, the team designed it so that it combines these living cells with ultra-low power electronics that convert the bacterial response into a wireless signal that can be read by a smartphone.
Publishing its findings in the journal Science, the team said that the altered cells are designed to respond to heme, a component of blood, as well as sensors that can respond to a molecule, a marker of inflammation.
The technology has been a decade in the making, following the work of synthetic biologists to engineer bacteria to respond to pollutants or markers of disease by emitting light. Until now, though, specialised equipment has been needed to see it.
Could diagnose multiple conditions
So, to make it more applicable in the real world, the MIT team decided to combine the bacteria with an electronic chip, which could then use the natural response as energy for the wireless signal.
In terms of size, the sensor is a cylinder measuring about 1.5in long and only requires 13 microwatts of power.
Equipped in the sensor is a 2.7V battery, which should be enough to power the sensor for more than a month, but the team has said that it could also be powered by a voltaic cell sustained by acidic fluids in the stomach.
The device has so far been tested in pigs and this showed it could correctly determine whether any blood was present in the stomach.
The researchers anticipate that this type of sensor could be either deployed for one-time use or designed to remain in the digestive tract for several days or weeks, sending continuous signals.
“The goal with this sensor is that you would be able to circumvent an unnecessary procedure by just ingesting the capsule and, within a relatively short period of time, you would know whether or not there was a bleeding event,” said Mark Mimee, one of the lead authors on the paper.
In the future, the team hopes to find a way to design the sensor pill to carry multiple strains of bacteria, allowing for the diagnosis of a variety of conditions.
