Abstract
Conventional metal electrodes generate electrochemical byproducts during stimulation of nerve or muscle. These byproducts may cause tissue damage, especially with the long-term stimulation necessary with neural prosthetic devices. To prevent the possibility of such damage, completely insulated electrodes have been devised which deliver current pulses by capacitive charging of the electrode surface, not involving electrochemical reactions. Anodised discs of porous tantalum, 1·0 mm in diameter and 0·25 mm thick, can deliver 0·5 ms, 5 mA pulses. Such electrodes are available as components of commercial capacitors and are easily adapted for biological use. The design may be optimised by mathematical analysis of an equivalent electrical circuit. In vitro tests demonstrate a clear advantage of these electrodes over capacitively coupled platinum-iridium electrodes in preventing oxidation-reduction reactions. The electrodes are stable on chronic implantation and should provide a safer interface between neural prosthetic devices and human tissue.
Original language | English (US) |
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Pages (from-to) | 613-620 |
Number of pages | 8 |
Journal | Medical & Biological Engineering |
Volume | 12 |
Issue number | 5 |
DOIs | |
State | Published - Sep 1974 |
Externally published | Yes |
Keywords
- Electrode
- capacitor
- prosthesis
- stimulation
ASJC Scopus subject areas
- General Engineering