Ion transistors that are completely biocompatible with humans are presented – wearable electronics will become implanted

Scientists from Oxford University have presented technology for manufacturing logic circuits that are fully compatible with human biology. Instead of electrons, “human electronics” use ion exchange. This is also a transfer of charges, which can be programmed and controlled. From tiny drops of hydrogel, you can create diodes, transistors, memory and logic elements that will perceive electrical signals from the human body and transmit them back.

Image source: University of Oxford

The researchers even came up with a name for the new electronics: dropletronics. Each droplet has a volume of several nanoliters and, depending on the composition, can have cationic (p) or anionic (n) conductivity, similar to transitions in semiconductors. Thus, diodes, transistors and logic circuits can be created from droplets with different conductivities. As an example, the researchers developed an electronic circuit capable of counting heart rhythms using signals directly from the heart muscle.

Scientists have previously used ionic conduction to create logic elements, but all previous work was based on solid substrates. The development of British scientists is distinguished by the fact that it is completely soft – after all, what could be softer than a drop of hydrogel? This provides a new advantage: such electronics will be fully compatible with the biosystem of the human body, both at the physical and signal levels. The body can be modernized by implanting electronic devices both for medical purposes and to improve the quality of life.

Separately, the researchers expressed hope that the capletronics they proposed would contribute to the development of neuromorphic computing that most closely imitates the functioning of the human brain. If the implanted computing device does not have enough power, scientists have already provided a solution – a droplet lithium-ion battery. But that will be a different story.