Light driven process prints biocompatible plastic electrodes

by Robert Schreiber
Linkoping, Sweden (SPX) Dec 16, 2025
Researchers at Linkoping University and Lund University have demonstrated that visible light can drive the formation of conductive polymer electrodes from water based solutions without hazardous chemicals. The method produces electrodes on many different substrates, including glass, textiles and even skin, which supports new types of electronic and medical sensor applications.

The work is based on conjugated polymers, a class of conductive plastics that combine the electrical behavior of metals and semiconductors with the mechanical properties of polymers. In the new approach, specially designed water soluble monomers undergo polymerisation when exposed to visible light, eliminating the need for strong or toxic reagents and avoiding harmful ultraviolet exposure.

In use, a solution containing the monomers is deposited onto a surface and exposed to a patterned light source, such as a laser or other visible light illumination, which defines the electrode geometry. The unpolymerised solution is then rinsed away, leaving behind patterned electrodes whose shapes are set by the light exposure.

"I think this is something of a breakthrough. It's another way of creating electronics that is simpler and doesn't require any expensive equipment," says Xenofon Strakosas, assistant professor at the Laboratory of Organic Electronics, LOE, at Linkoping University. According to the team, the use of visible light from simple LED lamps, such as party lights, is sufficient to drive the polymerisation.

The resulting material conducts both electrons and ions, allowing direct coupling to biological systems. "The electrical properties of the material are at the very forefront. As the material can transport both electrons and ions, it can communicate with the body in a natural way, and its gentle chemistry ensures that tissue tolerates it - a combination that is crucial for medical applications," says Tobias Abrahamsson, researcher at LOE and lead author of the article in Angewandte Chemie.

To evaluate the method in a biological context, the researchers photo patterned electrodes directly on the skin of anaesthetised mice. These polymer electrodes recorded low frequency brain activity with better performance than traditional metal EEG electrodes, demonstrating improved signal quality in this frequency range.

Because the process works on many surfaces and does not rely on aggressive solvents, the team points to potential use in wearable sensors integrated into garments and in large scale production of organic electronic circuits. The combination of visible light processing, aqueous chemistry and substrate versatility suggests a route toward scalable bioelectronic interfaces and soft electronic devices.

Research Report:Visible-Light-Driven Aqueous Polymerization Enables in Situ Formation of Biocompatible, High-Performance Organic Mixed Conductors for Bioelectronics