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PubMed · 3839437

Ca2+-selective microelectrodes.

D Ammann
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Abstract

Ca2+-selective microelectrodes based on the synthetic neutral carrier ETH 1001 can be used for quantitative intracellular measurements of resting Ca2+-activities and of slowly changing Ca2+-levels (response time in the order of seconds). Microelectrodes with tip diameters greater than 0.3 micron show selectivities that yield a detection limit between 10(-8) and 10(-7) M Ca2+ in an intracellular background. The Ca2+-activity is obtained together with electrical parameters of the cell (e.g. cell membrane potential and membrane resistance or conductivity). Simultaneous monitoring of other ion-activities is accessible (double- or multi-barrelled microelectrodes). The Ca2+-determination is extremely local, i.e. it probably does not indicate an averaged cytosolic activity in every situation (e.g. localized transients).

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CalciumCation Exchange ResinsCytoplasmDiaminesElectrochemistryMicroelectrodesPotentiometryTime FactorsJournal ArticleResearch Support, Non-U.S. Gov't

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D Ammann. 1985. Ca2+-selective microelectrodes.. https://doi.org/10.1016/0143-4160(85)90033-8

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