Poly(3,4‐Ethylenedioxythiophene)/Functional Gold Nanoparticle films for Improving the Electrode‐Neural Interface

Abstract

AbstractImplantable neural electrodes are indispensable tools for recording neuron activity, playing a crucial role in neuroscience research. However, traditional neural electrodes suffer from limited electrochemical performance, compromised biocompatibility, and tentative stability, posing great challenges for reliable long‐term studies in free‐moving animals. In this study, a novel approach employing a hybrid film composed of poly(3,4‐ethylenedioxythiophene)/functional gold nanoparticles (PEDOT/3‐MPA‐Au) to improve the electrode–neural interface is presented. The deposited PEDOT/3‐MPA‐Au demonstrates superior cathodal charge storage capacity, reduced electrochemical impedance, and remarkable electrochemical and mechanical stability. Upon implantation into the cortex of mice for a duration of 12 weeks, the modified electrodes exhibit notably decreased levels of glial fibrillary acidic protein and increased neuronal nuclei immunostaining compared to counterparts utilizing poly(3,4‐ethylenedioxythiophene)/poly(styrene sulfonate). Additionally, the PEDOT/3‐MPA‐Au modified electrodes consistently capture high‐quality, stable long‐term electrophysiological signals in vivo, enabling continuous recording of target neurons for up to 16 weeks. This innovative modification strategy offers a promising solution for fabricating low‐impedance, tissue‐friendly, and long‐term stable neural interfaces, thereby addressing the shortcomings of conventional neural electrodes. These findings mark a significant advancement toward the development of more reliable and efficacious neural interfaces, with broad implications for both research and clinical applications.