title: Novel multi-sided, microelectrode arrays for implantable neural applications.
abstract: A new parylene-based microfabrication process is presented for neural recording and drug delivery applications. We introduce a large design space for electrode placement and structural flexibility with a six mask process. By using chemical mechanical polishing, electrode sites may be created top-side, back-side, or on the edge of the device having three exposed sides. Added surface area was achieved on the exposed edge through electroplating. Poly(3,4-ethylenedioxythiophene) (PEDOT) modified edge electrodes having an 85-μm(2) footprint resulted in an impedance of 200 kΩ at 1 kHz. Edge electrodes were able to successfully record single unit activity in acute animal studies. A finite element model of planar and edge electrodes relative to neuron position reveals that edge electrodes should be beneficial for increasing the volume of tissue being sampled in recording applications.
authors.affiliation: Department of Electrical Engineering, University of Michigan, Ann Arbor, MI 48019, USA. seymourj@umich.edu
authors.forename: John P
authors.initials: JP
authors.lastname: Seymour
authors.forename: Nick B
authors.initials: NB
authors.lastname: Langhals
authors.forename: David J
authors.initials: DJ
authors.lastname: Anderson
authors.forename: Daryl R
authors.initials: DR
authors.lastname: Kipke
mesh_terms: D000818:Animals; D001921:Brain / Q000502:physiology; D017097:Electric Impedance; D055724:Electrophysiological Phenomena; D020342:Finite Element Analysis; D008297:Male; D008839:Microelectrodes; D055616:Microtechnology / Q000295:instrumentation*; D011108:Polymers / Q000737:chemistry; D019736:Prostheses and Implants; D051381:Rats; D017207:Rats, Sprague-Dawley; D012822:Silicon Dioxide / Q000737:chemistry; D014992:Xylenes / Q000737:chemistry
chemical_list: D011108:Polymers; D014992:Xylenes; C011055:parylene; D012822:Silicon Dioxide