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PubMed · 8788062

Toward the ultimate metal microelectrode.

G E Loeb·R A Peck·J Martyniuk
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Abstract

The performance of metal microelectrodes for stimulating and recording neuronal action potentials depends on precise control of their geometrical, electrical and mechanical properties. We describe a combination of materials whose properties approach fundamental physical limitations on achievable performance and reproducible fabrication techniques that provide probes with very small dimensions. Pure iridium wire is electrolytically sharpened, vapor-coated with Parylene-C insulation and the tip exposed using an automatically steerable UV laser. Electrochemical activation of the iridium increases the capacitance of the metal-electrolyte interface so that the overall impedance in the relevant frequency band (100-10,000 Hz) is dominated by the access resistance of the surrounding tissues.

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Electric ConductivityElectric ImpedanceElectrochemistryElectrophysiologyIridiumMicroelectrodesPolymersXylenesJournal Article

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BibTeXRIS

G E Loeb, R A Peck, J Martyniuk. 1995. Toward the ultimate metal microelectrode.. https://doi.org/10.1016/0165-0270(95)00107-7

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