Ultra-Flexible Multichannel Neural Microelectrodes Modified by PEDOT:PSS/IrOx for Enhanced Sensing and Localized Stimulation

We report an ultra-flexible multi-channel neural electrode with a novel modified approach to achieve the performance of high charge storage capacity. This kind of neural electrodes possess the thickness of ~ 2.5 μm, the width of ~ 100 μm, and bending stiffness of ~3.9×10
^-13
N•m
²
, which testify to its outstanding flexibility, higher biocompatibility and working stability. Moreover, ultrathin flexible neural electrode modified with PEDOT: PSS/IrOx has a high charge storage capacity of ~ 24.2 mC/cm
²
, which is ~ 27.9 times and ~1.6 times of PEDOT:PSS and IrOx alone, presenting superior performance in electrical stimulation. The extremely thin thickness and modified nanomaterials both benefit long-term high-quality neurophysiological signal recording. By implanting the ultraflexible neural electrode, it was verified that the modified electrode had long-term stable signal recording ability for 6 weeks and good localized electrical stimulation effect, which demonstrated to be a powerful tool for the research of brain neuroscience.