title: Regenerative scaffold electrodes for peripheral nerve interfacing.
abstract: Advances in neural interfacing technology are required to enable natural, thought-driven control of a prosthetic limb. Here, we describe a regenerative electrode design in which a polymer-based thin-film electrode array is integrated within a thin-film sheet of aligned nanofibers, such that axons regenerating from a transected peripheral nerve are topographically guided across the electrode recording sites. Cultures of dorsal root ganglia were used to explore design parameters leading to cellular migration and neurite extension across the nanofiber/electrode array boundary. Regenerative scaffold electrodes (RSEs) were subsequently fabricated and implanted across rat tibial nerve gaps to evaluate device recording capabilities and influence on nerve regeneration. In 20 of these animals, regeneration was compared between a conventional nerve gap model and an amputation model. Characteristic shaping of regenerated nerve morphology around the embedded electrode array was observed in both groups, and regenerated axon profile counts were similar at the eight week end point. Implanted RSEs recorded evoked neural activity in all of these cases, and also in separate implantations lasting up to five months. These results demonstrate that nanofiber-based topographic cues within a regenerative electrode can influence nerve regeneration, to the potential benefit of a peripheral nerve interface suitable for limb amputees.
authors.affiliation: Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332 USA. isaac.clements@gmail.com
authors.forename: Isaac P
authors.initials: IP
authors.lastname: Clements
authors.forename: Vivek J
authors.initials: VJ
authors.lastname: Mukhatyar
authors.forename: Akhil
authors.initials: A
authors.lastname: Srinivasan
authors.forename: John T
authors.initials: JT
authors.lastname: Bentley
authors.forename: Dinal S
authors.initials: DS
authors.lastname: Andreasen
authors.forename: Ravi V
authors.initials: RV
authors.lastname: Bellamkonda
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology; D062207:Brain-Computer Interfaces; D002452:Cell Count; D002465:Cell Movement; D004558:Electric Stimulation / Q000295:instrumentation*; D004566:Electrodes; D004567:Electrodes, Implanted; D055724:Electrophysiological Phenomena; D005121:Extremities / Q000502:physiology; D005727:Ganglia, Spinal / Q000502:physiology; D007150:Immunohistochemistry; D008297:Male; D057139:Nanofibers; D009416:Nerve Regeneration; D009924:Organ Culture Techniques; D010525:Peripheral Nerves / Q000502:physiology*; D019736:Prostheses and Implants; D011474:Prosthesis Design; D051381:Rats; D011917:Rats, Inbred Lew