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The goal of this study was to perform in situ electrochemical polymerization of poly(3,4-ethylenedioxythiophene) (PEDOT) in peripheral nerves to create a soft, precisely located injectable conductive polymer electrode for bi-directional communication. Intraneural PEDOT polymerization was performed to target both outer and inner fascicles via custom fabricated 3D printed cuff electrodes and monomer injection strategies using a combination electrode-cannula system. Electrochemistry, histology, and laser light sheet microscopy revealed the presence of PEDOT at specified locations inside of peripheral nerve. This work demonstrates the potential for using in situ PEDOT electrodeposition as an injectable electrode for recording and stimulation of peripheral nerves.
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Electropneumotactile Stimulation: Multimodal Haptic Actuators Enabled by a Stretchable Conductive Polymer on Inflatable Pockets
Abstract A type of haptic device is described that delivers two modes of stimulation simultaneously and at the same location on the skin. The two modes of stimulation are mechanical (delivered pneumatically by inflatable air pockets embedded within a silicone elastomer) and electrical (delivered by a conductive polymer). The key enabling aspect of this work is the use of a highly plasticized conductive polymer based on poly(3,4‐ethylenedioxythiphene) (PEDOT) blended with elastomeric polyurethane (PU). To fabricate the “electropneumotactile” device, the polymeric electrodes are overlaid directly on top of the elastomeric pneumatic actuator pockets. Co‐placement of the pneumatic actuators and the electrotactile electrodes is enabled by the stretchability of the PEDOT:tosylate/PU blend, allowing the electrotactiles to conform to underlying pneumatic pockets under deformation. The blend of PEDOT and PU has a Young's modulus of ≈150 MPa with little degradation in conductivity following repeated inflation of the air pockets. The ability to perceive simultaneous delivery of two sensations to the same location on the skin is supported by experiments using human subjects. These results show that participants can successfully detect the location of pneumatic stimulation and whether electrotactile stimulation is delivered (yes/no) at a rate significantly above chance (mean accuracy = 94%).
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- Award ID(s):
- 1929748
- PAR ID:
- 10458254
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 5
- Issue:
- 6
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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