A collaboration between scientists atTufts School of Engineering at the University of Illinois has led to the creation oftiny, fully biocompatible electronic devices that, once they have functioned for a set period of time, dissolve harmlessly into their surroundings. The devices, dubbed “transient electronics”, are thought to be the next-generation of medical devices, and could lead to a range of implants that never need surgical removal – not to mention that they are fully compostable.
“These devices are the polar opposite of conventional electronics whose integrated circuits are designed for long-term physical and electronic stability,” says Fiorenzo Omenetto, professor of biomedical engineering at Tufts School of Engineeringin a statement. “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, depending on the application. Imagine the environmental benefits if cell phones, for example, could just dissolve instead of languishing inlandfillsfor years.”
The report, titled A Physically Transient Form of Silicon Electronics, was published in the September 28, 2012, issue of Science and described how the futuristic devices incorporate the materials of conventional integrated circuits, but in an ultrathin form that is then encapsulated in silk protein.
“While silicon may appear to be impermeable, eventually it dissolves in water,” Omenetto said. Though he added though that for the team, the main challenge was to make the electrical components dissolve in minutes rather than eons.
The result was ultrathin flexible electronic components that are a mere tens of nanometers thick. The tiny electronics were then designed to dissolve by sheets of silk protein in which the electronics are supported and encapsulated. Extracted from silkworm cocoons, silk protein is one of the strongest, most robust materials known. It’s also fully biodegradable and biofriendlyand is already used in some medical applications.
It is hoped that the next iteration of medical devices will be designed to respond to changes in their environment, such as chemistry, light or pressure.
+ Tufts School of Engineering