Title :
In vitro comparison of the charge-injection limits of activated iridium oxide (AIROF) and platinum-iridium microelectrodes
Author :
Cogan, Stuart F. ; Troyk, Philip R. ; Ehrlich, Julia ; Plante, Timothy D.
Author_Institution :
EIC Labs. Inc., Norwood, MA, USA
Abstract :
The charge-injection limits of activated iridium oxide electrodes (AIROF) and PtIr microelectrodes with similar geometric area and shape have been compared in vitro using a stimulation waveform that delivers cathodal current pulses with current-limited control of the electrode bias potential in the interpulse period. Charge-injection limits were compared over a bias range of 0.1-0.7 V (versus Ag|AgCl) and pulse frequencies of 20, 50, and 100 Hz. The AIROF was capable of injecting between 4 and 10 times the charge of the PtIr electrode, with a maximum value of 3.9 mC/cm 2 obtained at a 0.7 V bias and 20 Hz frequency.
Keywords :
charge injection; iridium compounds; microelectrodes; platinum compounds; 0.1 to 0.7 V; 100 Hz; 20 Hz; 50 Hz; IrO; PtIr; activated iridium oxide microelectrodes; cathodal current pulses; charge-injection limits; electrode bias potential; platinum-iridium microelectrodes; Charge transfer; Electrodes; Frequency; In vitro; Microelectrodes; Oxidation; Pulse shaping methods; Shafts; Shape control; Voltage; Charge-injection; current pulsing; iridium oxide; microelectrode; neural stimulation; platinum-iridium; Electric Impedance; Electric Stimulation; Electrostatics; Equipment Design; Equipment Failure Analysis; Iridium; Microelectrodes; Platinum Compounds;
Journal_Title :
Biomedical Engineering, IEEE Transactions on
DOI :
10.1109/TBME.2005.851503
