title: Microchannel neural interface manufacture by stacking silicone and metal foil laminae.
abstract: Microchannel neural interfaces (MNIs) overcome problems with recording from peripheral nerves by amplifying signals independent of node of Ranvier position. Selective recording and stimulation using an MNI requires good insulation between microchannels and a high electrode density. We propose that stacking microchannel laminae will improve selectivity over single layer MNI designs due to the increase in electrode number and an improvement in microchannel sealing.
  
  
  
  This paper describes a manufacturing method for creating MNIs which overcomes limitations on electrode connectivity and microchannel sealing. Laser cut silicone-metal foil laminae were stacked using plasma bonding to create an array of microchannels containing tripolar electrodes. Electrodes were DC etched and electrode impedance and cyclic voltammetry were tested.
  
  
  
  MNIs with 100 μm and 200 μm diameter microchannels were manufactured. High electrode density MNIs are achievable with electrodes present in every microchannel. Electrode impedances of 27.2 ± 19.8 kΩ at 1 kHz were achieved. Following two months of implantation in Lewis rat sciatic nerve, micro-fascicles were observed regenerating through the MNI microchannels.
  
  
  
  Selective MNIs with the peripheral nervous system may allow upper limb amputees to control prostheses intuitively.
authors.affiliation: University College London, John Scales Centre for Biomedical Engineering, Institute of Orthopaedics and Musculoskeletal Science, RNOHT, Stanmore HA7 4LP, UK.
authors.forename: Henry T
authors.initials: HT
authors.lastname: Lancashire
authors.forename: Anne
authors.initials: A
authors.lastname: Vanhoestenberghe
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Pendegrass
authors.forename: Yazan Al
authors.initials: YA
authors.lastname: Ajam
authors.forename: Elliot
authors.initials: E
authors.lastname: Magee
authors.forename: Nick
authors.initials: N
authors.lastname: Donaldson
authors.forename: Gordon W
authors.initials: GW
authors.lastname: Blunn
mesh_terms: D000818:Animals; D062207:Brain-Computer Interfaces; D017097:Electric Impedance; D004566:Electrodes; D004567:Electrodes, Implanted; D019544:Equipment Failure Analysis; D007368:Interferometry; D008297:Male; D008670:Metals / Q000737:chemistry*; D009474:Neurons / Q000502:physiology*; D010525:Peripheral Nerves / Q000502:physiology; D011474:Prosthesis Design; D051381:Rats; D011917:Rats, Inbred Lew; D012828:Silicones / Q000737:chemistry*
chemical_list: D008670:Metals; D012828:Silicones