Abstract
A tetrode is a bundle of four microwires that can record from multiple neurons simultaneously in the brain of a freely moving animal. Tetrodes are usually electroplated to reduce impedances from 2-3 MΩ to 200-500 kΩ (measured at 1 kHz), which increases the signal-to-noise ratio and allows for the recording of small-amplitude signals. Tetrodes with even lower impedances could improve neural recordings but cannot be made using standard electroplating methods without shorting. We were able to electroplate tetrodes to 30-70 kΩ by adding polyethylene glycol (PEG) or multi-walled carbon nanotube (MWCNT) solutions to a commercial gold-plating solution. The MWCNTs and PEG acted as inhibitors in the electroplating process and created large surface area, low-impedance coatings on the tetrode tips.
Original language | English (US) |
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Pages (from-to) | 388-393 |
Number of pages | 6 |
Journal | Sensors and Actuators, A: Physical |
Volume | 156 |
Issue number | 2 |
DOIs | |
State | Published - Dec 2009 |
Bibliographical note
Funding Information:This work was supported by a grant from the University of Minnesota Institute for Engineering in Medicine (IEM) and an NIH T32-EB008389 training grant. Parts of this work were carried out in the Minnesota Characterization Facility, which receives partial support from NSF through the NNIN program.
Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
Keywords
- Carbon nanotubes
- Electroplating
- Extracellular recording
- Impedance
- Tetrodes