Dissolvable Electronics Designed to Monitor Health

It’s almost commonplace in science fiction for characters’ bodies to be filled with tiny computers for any number of purposes. While we may not have body-dwelling nanomachines yet, researchers have developed tiny electronic sensing devices that can be placed inside the brain which are capable of dissolving harmlessly once their job is done.

Smaller than a grain of rice, these temporary sensors are capable of measuring pressure, temperature, pH, motion, flow, and potentially specific biomolecules, and while they were originally designed for usage in the brain, they could potentially be used in any number of other organs. The advantage to the use of these tiny electronics is the potential to free patients from the cumbersome and potentially invasive equipment that is currently used to monitor them. The authors of its scientific paper believe that the sensors could help those with a wide variety of ailments, from complex brain injuries to diabetics.

Created through the efforts of Rory Murphy of Washington University School of Medicine and John Rogers’ group at the University of Illinois at Urbana-Champaign, the main design of the diminutive sensors comprises of biodegradable silicon-based piezoresistive materials that change resistance under stress, as well as layers of magnesium, and a dissolvable copolymer and poly(lactic-co-glycolic acid) (PLGA). In short, the devices are made from materials already present in our bodies that we intake regularly. Wireless data transmission from the sensors is handled by dissolvable molybdenum wires that connect the sensor to a data transmission device that can be placed outside of the body, such as on the skin.

The lifetime of the devices is controlled by the thickness of their coatings, with thicker ones taking longer to dissolve. Currently, the longest lifespan of the devices when covered in biofluids is only a few days, but Murphy is hopeful that this lifespan could be extended to weeks. Testing so far has taken place with rats, allowing the researchers to both test the collection of  temperature and pressure data as well as closely track the breakdown of the sensor, to check whether it’s degradation had any effect on the animal’s brain. Thankfully there are yet to be any clear complications as a result of using the sensors.

It is still only a proof of concept at this stage, but the results are certainly promising. In the future systems such as these could go a long way towards medical advances due to the ability to collect biometric data that would require traumatic invasive surgery with our current technology. Some may still fear the idea of computers in their brains, but at least these ones aren’t permanent.

The full paper published to the journal Nature can be found here.

Image credit to J Rogers, University of Illinois