Dissolvable electronics one step closer

The possibilities for medical research and treatment could get a huge boost thanks to research that’s taken us one step closer to creating tiny electronic sensors and devices that can be implanted in the body and then dissolve once they’ve completed their task.

A research team has created a dissolvable device component out of egg proteins, magnesium and tungsten. They’ve reported their findings in ACS Applied Materials & Interfaces.

Transient electronics have many potential applications, from localised drug delivery to pollution monitoring. To explore these possibilities, scientists have been working with an array of natural materials to test how well they perform in electronic devices and whether they might cause side effects or damage when implanted. Unlike conventional electronics that contribute to a growing amount of harmful waste, dissolvable devices are designed to be compatible with the environment. Jikui Luo, Xiaozhi Wang and colleagues wanted to build on this work and develop a transient memory resistor with dissolvable components.

This electronic component, also called a memristor, is a new type of resistor that regulates the flow of electric current and can also ‘remember’ charges.

The researchers rapidly spun diluted egg albumin, the white part of an egg, on a silicon wafer to turn it into an ultrathin film. Then they incorporated electrodes made out of magnesium and tungsten. Testing showed that the device’s performance matched that of non-degradable memristors.

Under dry conditions in the lab, the components worked reliably for more than three months. In water, the electrodes and albumin dissolved in 2–10 h in the lab. The rest of the chip took about three days to break down, leaving minimal residue behind.

Image caption: A new electronic component partly made with egg proteins could help enable dissolvable devices. Image credit: American Chemical Society.