Year-end Sale % OFF 
Abstract
Abstract Long-term interfacing with neural tissue is key for the diagnosis and therapy of neurological disorder. Coatings with dedicated micro- and nanostructures have been proposed, such as gold nanowires, platinum nanostructured by electrochemical roughening, columnar and porous titanium nitride, carbon nanotubes, and conductive polymers. The performance of these coatings, however, is limited because of the mechanical mismatch between implant and neural tissue. Herein, we show that micro- and nanostructured, soft and conductive elastomer films can be obtained by depositing gold on nanometer-thin thiol-functionalized polydimethylsiloxane (PDMS) films. Additionally, microstructured polyether ether ketone (PEEK) films enable directional ordering in topology. The formation of soft and conductive PDMS films with oriented wrinkles on the macroscopic scale was controlled by the ratio between the metal/elastomter thicknesses and the depth of thermally imprinted trenches. Four-point probe measurements revealed that the electrical conductivity is one order of magnitude higher than that of recently presented hydrogel formulations. Nano-indentations proved that the submicrometer-thin conductive elastomer exhibit an average elastic modulus well below 10 MPa. This material system can be made tens of micrometers thin, and, therefore, has the potential to address several challenges of current implantable neural interfaces for the central nervous system, e.g. fabrication of softer and more flexible micrometer-thin spinal cord arrays.
Highlights
There has been growing excitement around treating neurological diseases and spinal cord injuries using neuromodulation techniques [1,2]
The conducting elastomer film consists of a 350 nm-thin thiol-functionalized PDMS film with embedded gold
The PDMS film improved the adhesion to the high-power impulse magnetron sputtering (HiPIMS) sputtered titanium film and enable an irreversible bonding to the microstructured polymer substrate [31,32,33]
Summary
There has been growing excitement around treating neurological diseases and spinal cord injuries using neuromodulation techniques [1,2]. The elastic modulus of state-of-theart platinum‐iridium or titanium electrodes, which represent the actual neural interface, differs by orders of magnitude from that of neural tissue [7]. Developed conductive and soft neural interfaces were reducing the gap of the mechanical mismatch between the manmade system and the neural tissue [7,9,10]. Tybrandt et al proposed a soft composite of gold-coated titanium dioxide nanowires embedded in a silicone matrix [11]. Conductive and ultrasoft poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) hydrogels are promising as they mimic the mechanical properties of neural tissue [13,14,15]. The common weaknesses of such hydrogel systems, are the delamination from the carrier/substrate and their restricted electrical conductivity [16]. Further challenges of future biomimetic and soft electrodes include functionalization by e.g. chemical modification, a strong adhesion of the electrode to the substrate, and the achievement of appropriate signal-to-noise ratio for a reasonable time period in vivo
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
