FrogHeart

Key Obstacle to Integrated Bioelectronic Implants Removed with Use of Solid-State Hydrogel

Swedish researchers have created a photo‑patternable solid‑state hydrogel electrolyte using i‑carrageenan and PEGDA, achieving ionic conductivity above 10 mS cm⁻¹ and feature sizes down to 15 µm. The material replaces liquid electrolytes in organic electrochemical transistors (OECTs), enabling fast, dense, and flexible circuits that can be implanted without leakage. A proof‑of‑concept spiking neuron circuit was wrapped around the mouse vagus nerve, producing controlled heart‑rate reductions while remaining stable after implantation. The work demonstrates a scalable path toward reliable bioelectronic therapies.