About event
Implantable microelectrode arrays are crucial tools in neuroscience to study neural functions as well as disorders like Parkinson's disease, epilepsy, and spinal cord injuries. Despite advancements in neuro-device technology, challenges persist with rigid-metal-based arrays. These devices often cause mechanical mismatches with brain tissue, leading to chronic inflammation, tissue damage, and compromised performance. There is increasing interest in developing flexible electrodes to mitigate these issues.
Our approach to bridging the mechanical mismatch gap involves utilizing gallium-based electrodes for flexible neural implants. Gallium-based materials offer several advantages, including soft mechanical properties, minimal cytotoxicity, and excellent electrical conductivity. Gallium electrodes are initially rigid for implantation but phase into a liquid state post-insertion due to their low melting point, reducing the mechanical mismatch with neural tissue.We electrochemically deposited conductive polymer poly(3,4-ethylenedioxythiophene) PEDOT doped with tetrafluoroborate (BF4) to contain the liquid gallium, preserve its' electrochemical properties and enhance the device biocompatibility. PEDOT: BF4 demonstrates excellent electrochemical and thermochemical performance, low impedance, and good biocompatibility. We characterize the electrochemical properties, thermal stability, and morphology of PEDOT:BF₄ - coated gallium electrodes, showing strong structural integrity and stability over five weeks in vitro. Acute in vitro and in vivo tests confirm their ability to record neural activity. Chronic implantation in rats demonstrates device functionality lasting eight weeks.
This talk will explore our flexible gallium-based neural arrays capped with PEDOT: BF4 for chronic in vivo applications. Our findings indicate that these gallium-based, PEDOT: BF4-coated neuro devices exhibit superior biocompatibility compared to traditional rigid, metal arrays.
