MIT researchers have developed a small battery that runs on stomach acids and is capable of powering e-pills to monitor patient health.
The small system can generate enough power to run small sensors or drug delivery devices that can reside in the gastrointestinal tract for long periods of time.
For this battery, researchers used idea of very simple type of voltaic cell, lemon battery that produces electric current between the two electrodes stuck in a lemon due to its citric acid.
To replicate it, the researchers attached zinc and copper electrodes to the surface of their ingestible sensor.
The zinc emits ions into the acid in the stomach to power the voltaic circuit.
It can generate enough energy to power a commercial temperature sensor and a 900-megahertz transmitter to wirelessly transmit the data to a base station located 2 metres away, with a signal sent every 12 seconds.
The current prototype of the device is a cylinder about 12 millimetres in diameter and 40 millimetres in length.
Researchers are anticipating to make the capsule about one-third that size.
It offers a safer and lower-cost alternative to the traditional batteries used to power such devices.
It can also help in manufacturing new generation of electronic ingestible pills.
This could enable novel ways of monitoring patient health and treating disease.
