Another major advance is demonstrated by the researchers in their Science Advances paper: enabling bioelectronic devices, specifically those implanted in the body for diagnostics or therapy, to interface effectively and safely with human tissue, while also making them capable of performing complex processing. Inspired by electrically active cells, similar to those in the brain that communicate with electrical pulses, the team created a single material capable of performing multiple, non-linear, dynamic electronic functions just by varying the size and density of its composite mixed-conducting particles.

Video describing the development of MCPs, mixed-conducting particulate composites that allow creation of electronic components out of a single material

“This innovation opens the door to a fundamentally different approach to electronic device design, mimicking biological networks and creating multifunctional circuits from purely biodegradable and biocompatible components,” says Khodagholy.

The researchers designed and created mixed conducting particulate (MCP)-based high performance anisotropic films, independently addressable transistors, resistors, and diodes that are pattern-free, scalable, and biocompatible. These devices carried out a variety of functions, including recording neurophysiologic activity from individual neurons, performing circuit operations, and bonding high-resolution soft and rigid electronics.

“MCP substantially reduces the footprint of neural interface devices, permitting recording of high-quality neurophysiological data even when the amount of tissue exposed is very small, and thus decreases the risk of surgical complications,” says Gelinas. “And because MCP is composed of only biocompatible and commercially available materials, it will be much easier to translate into biomedical devices and medicine.”

Both the E-IGTs and MCP hold great promise as critical components of bioelectronics, from wearable miniaturized sensors to responsive neurostimulators. The E-IGTs can be manufactured in large quantities and are accessible to a broad range of fabrication processes. Similarly, MCP components are inexpensive and easily accessible to materials scientists and engineers. In combination, they form the foundation for fully implantable biocompatible devices that can be harnessed both to benefit health and to treat disease.

Khodagholy and Gelinas are now working on translating these components into functional long-term implantable devices that can record and modulate brain activity to help patients with neurological diseases such as epilepsy.

“Our ultimate goal is to create accessible bioelectronic devices that can improve peoples’ quality of life,” says Khodagholy, “and with these new materials and components, it feels like we have stepped closer to that.”