Ion-selective microelectrodes suitable for recording rapid changes in extracellular ion concentration.
A method for fabricating double-barrel, ion-selective microelectrodes with fine tips (0.5-1.5 microns) and rapid response times is described. When made into K(+)-selective microelectrodes, the electrodes respond to changes in [K+]o with a time constant of 70-95 ms. The electrical response of these electrodes to common-mode voltages can be made to have a time constant of less than 2 ms, which minimizes electrical artifacts from field potentials. The application of these microelectrodes to the measurement of rapid, transient changes in retinal [K+]o is presented.
Wen
R
R
Neuroscience Program, University of Illinois, Urbana-Champaign 61801-2991.
Oakley
B
B
D000818:Animals; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D005110:Extracellular Space / Q000032:analysis*; D008839:Microelectrodes; D010775:Photic Stimulation; D012160:Retina / Q000032:analysis* / Q000502:physiology