Rapid 3D printing of PEDOT:PSS-based flexible bio-electrodes

Abstract

The integration of biotechnology and information technology has created a growing demand for high-performance flexible bio-electrodes. However, existing conductive polymer systems often struggle to simultaneously achieve high electrical conductivity, excellent stretchability, and high-resolution circuitry that are essential for soft bioelectronics. To address these challenges, we developed a light-curable, elastomeric bio-electrode consisting of a dual-network conductive hydrogel system combining poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) with a photo-crosslinkable Pluronic hydrogel. Utilizing digital light processing (DLP)-based three-dimensional (3D) printing technology, this bio-electrode can be rapidly prototyped with customized, high-resolution electrode structures and tailored packaging. Subsequent acid treatment induces molecular chain rearrangement within the electrode, resulting in a denser network topology and significantly enhanced electrical conductivity. Consequently, these flexible electrodes exhibit excellent electrical performance exceeding 300 S/m, while maintaining remarkable flexibility and stretchability. The fabricated electrodes demonstrate good biocompatibility and are capable of delivering electrical stimulation to biological tissues or recording cortical neural signals. This approach provides an efficient strategy for customizing high-performance flexible bio-electrodes, holding significant promise for future medical applications.