Ultra-thin electronics that dissolve inside the body have been devised by scientists in the US and could be used for a range of medical roles.
The devices can “melt away” once their job is done, according to research published in the journal Science.
The technology has already been used to heat a wound to keep it free from infection by bacteria.
The components are made of silicon and magnesium oxide, and placed in a protective layer of silk.
It is part of a field termed “transient electronics” and comes from researchers who have already developed “electronic tattoos” – sensors that bend and stretch with the skin.
They described their vanishing devices as the “polar opposite” of traditional electronics, which are built to be stable and to last.
Getting the electronics to fade away in a controlled manner relies on two scientific developments – getting the electronics to dissolve at all and using a shell to control when that happens.
Silicon dissolves in water anyway. The problem is that the size of components in conventional electronics means it would take an eternity. The researchers used incredibly thin sheets of silicon, called a nanomembrane, which can dissolve in days or weeks.
The speed of melting is controlled by silk. The material is collected from silkworms, dissolved and then allowed to reform. Altering the way the dissolved silk crystallises changes its final properties – and how long the device will last.
Prof Fiorenzo Omenetto, from Tufts school of engineering, said: “Transient electronics offer robust performance comparable to current devices but they will fully resorb into their environment at a prescribed time, ranging from minutes to years.”
A range of uses have already been tested in the laboratory including a 64-pixel digital camera, temperature sensors and solar cells.
John Rogers, a mechanical science and engineering professor at the University of Illinois, said: “It’s a new concept, so there are lots of opportunities, many of which we probably have not even identified yet.”