title: Microtube-based electrode arrays for low invasive extracellular recording with a high signal-to-noise ratio.
abstract: We report on the development of a microtube electrode array as a neural interface device. To combine the desired properties for the neural interface device, such as low invasiveness with a small needle and a good signal-to-noise ratio in neural recordings, we applied the structure of a glass pipette electrode to each microtube electrode. The device was fabricated as sub-5-microm-diameter out-of-plane silicon dioxide microtube arrays using silicon microneedle templates, which are grown by the selective vapor-liquid-solid method. The microtubes had inner diameters of 1.9-6.4 microm and a length of 25 microm. Impedances ranged from 220 kOmega to 1.55 MOmega, which are less than those for conventional microneedles. In addition, the microtube electrodes had less signal attenuation than conventional microneedle electrodes. We confirmed that the effects of parasitic capacitances between neighboring microtubes and channels were sufficiently small using a test signal. Finally, neural responses evoked from a rat peripheral nerve were recorded in vivo using a microtube electrode to confirm that this type of electrode can be used for both electrophysiological measurements and as a neural interface device.
authors.affiliation: Department of Electrical and Electronic Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka Tempaku-cho, Toyohashi, Aichi 441-8580, Japan. takei@dev.eee.tut.ac.jp
authors.forename: Kuniharu
authors.initials: K
authors.lastname: Takei
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kawano
authors.forename: Takahiro
authors.initials: T
authors.lastname: Kawashima
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Sawada
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Kaneko
authors.forename: Makoto
authors.initials: M
authors.lastname: Ishida
mesh_terms: D000818:Animals; D004567:Electrodes, Implanted; D004569:Electroencephalography / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008297:Male; D008839:Microelectrodes; D008904:Miniaturization; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014793:Visual Cortex / Q000502:physiology*