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Valinomycin-based K+ selective microelectrodes with low electrical membrane resistance.

D Ammann·P S Chao·W Simon
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Abstract

A valinomycin-based membrane phase for microelectrodes with relatively low electrical membrane resistances is described. Microelectrodes with tip diameters of about 1 micron exhibit resistances of about 10(10) omega. Extremely high K+ selectivities are obtained, e.g. a rejection of Na+ by a factor of 5000 and of acetylcholine by a factor of 3400. At a constant background of 140 and 500 mM Na+, the detection limit of the K+ sensor is at 1.6 X 10(-5) and at 2.5 X 10(-5) M K+, respectively.

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Electric ConductivityElectrochemistryMicroelectrodesNeurophysiologyPotassiumValinomycinJournal ArticleResearch Support, Non-U.S. Gov't

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D Ammann, P S Chao, W Simon. 1987-02-24. Valinomycin-based K+ selective microelectrodes with low electrical membrane resistance.. https://doi.org/10.1016/0304-3940(87)90153-4

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