Potassium selective microelectrode

VYSKOClL, F., KRIZ, N., and BURE , J. 1972. Potassium-selective microelectrodes used for measuring the extracellular brain potassium during spreading depression and anoxic depolarization in rats. Brain Research 39j 255-259. 

Gyurcsanyi, R. E., Nyback, A. S., Toth, K., Nagy, G., Ivaska, A., Novel polypyrrole based all-solid-state potassium-selective microelectrodes. AnaZy f 1998, 123(6), 1339-1344. 

The greater conductivity of an ion-exchanger solution containing the potassium salt of anion XVI in solvent 3-o-nitroxylene (Corning No. 476200) [13a] is a reason for the popularity of this system for electrophysiological measurements using ion-selective microelectrodes [216]. Application of this sensor is so widespread that only reviews and books will be mentioned, for microelectrodes in intracellular measurements [23, 32, 78, 86, 211, 217] and for the determination of K in the intercellular liquid [78]. A working valinomycin microelectrode has also been constructed [166]. 

Fig. 2a. Simultaneous recording of membrane PDs (upper) and potassium potentials (lower) by the two barrels of the double-barreled K -selective microelectrode.

Tarcah, J., Nagy, G., Toth, K., Pungor, E., Juhasz, G., KukoreUi, T., In vivo measurements with a potassium ion-selective microelectrode based on a new bis(crown ether). Anal Ghim Acta 1985, 178(2), 231-237. 

The ionophore N,N -diheptyl-N,N -dimethylsuccinic acid diamide (9) is considered the best available lipophilic ligand regarding selectivity for magnesium over the physiologically important ions of sodium, potassium and calcium (37). Glass microelectrodes filled with (9) (20 mass %), propylene... 

Chow, S.Y., D.L. Kunze, A.M. Brown, and A.M. Woodbury. 1970. Chloride and potassium activities in luminal fluid of turtle thyroid follicles as determined by ion selective ion-exchanger microelectrodes. Proc. Natl. Acad. Sci. 67 998-1004. 

Potassium is the major determinant of the electrophysiological properties of cells- renal epithelial cells being no exception (Windhager and Giebisch, 1965). This study utilizes a double-barreled K" "-selective liquid ion-exchange microelectrodes to... 

The selectivity coefficients of the microelectrodes were evaluated in equimolar pure solutions. The ionic strength of the standards was selected so as to approximate the value of intracellular fluid of Necturus proximal tubules. The intracellular K" and Cl concentrations were determined from the calibration curve of the respective microelectrode in standard solutions that flanked intracellular readings. The chloride microelectrode potential is insensitive to the cationic substitution of Na for K" " in the different solutions at constant ionic strength. It is also insensitive to changes in H concentration in the pH 4-8 range. Similarly, the potassium microelectrode potential is insensitive to the anionic substitution of H2P0 for Cl". 

Using double-barreled liquid ion-exchange microelectrodes intracellular potassium and chloride concentrations were measured simultaneously with membrane PDs in single cells of the proximal tubules of Necturus kidney. The electrometric method measured an intracellular potassium concentration which constituted about 3/4 of the total K content. There was a remarkable agreement between the calculated and measured E across the luminal and peritubular boundaries suggesting passive transport of K", an electrochemical equilibrium distribution and K -selectivity of both membranes. 

HINKE, J. A. M. The measurement of sodium and potassium activities in the squid axon by means of cations-selective glass microelectrodes. Journal of Physiology (London), 1961, 156 ... 

Khuri, R.N., Aguilian, S.K, and Wise, W.M. Potassium in the rat kidney proximal tubules situ determination by K -selective liquid ion-exchanger microelectrodes. Pflug. Arch. Ges. Physiol. 1971, 3, 39. 

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