Electronics are often bought with one thing in mind—how long are they going to last? A new class of electronics might be on its way to reversing this paradigm. New on the technology block are ‘transient electronics’ that dissolve in water, and importantly, body fluids.
From Use-and-throw to Use-and-Disappear
Researchers at the University of Illinois, Tufts University and Northwestern University have pioneered biocompatible electronics that are both robust and high performance, and also capable of dissolving and thus free of the problems of waste disposal that accompany conventional electronic goods.
The applications of this class of devices could be wide-ranging and important. Starting with medical implants that perform a biological function for a specified duration of time or record biological parameters before being resorbed into the body’s system, and moving to environmental monitors that dissolve and reduce environmental impact, these ‘transient electronics’ have great potential.
How Do They Dissolve?
The key to this invention is the use of ultra-thin silicon sheets which are so thin they easily dissolve. Used together with soluble conductors employing primarily magnesium and magnesium oxide, they offer the raw materials for a wide range of applications. Wireless power coils, radio transmitters and antennae, solar cells and temperature sensors are some devices that have already been constructed.
The engineers have also come up with a way to control the time after which these devices dissolve, by wrapping them in a layer of silk. It is the structure of the silk that determines the rate of dissolution. The timescales for dissolution can range from as small as a few minutes to days, weeks, months or potentially, years, all depending on the silk packaging.
You can read about this research here.