Thermo Fisher Scientific Ion Selective Electrodes Copper User Manual
Page 19
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Electrode Life
The Cupric Ion Electrodes will last six months in normal
laboratory use. On-line measurements might shorten operational
lifetime to several months. In time, the response time will
increase and the calibration slope will decrease to the point
calibration is difficult and electrode replacement is required.
Electrode Storage
The Cupric Ion Electrodes may be stored for short periods of time
in 1.0x10
-2
M cupric solution. For longer storage (longer than two
weeks), rinse and dry the sensing pellet and cover the membrane
tip with any protective cap shipped with the electrode. The
reference portion of the combination electrode (or the outer
chamber of the reference electrode) should be drained of filling
solution, if refillable, and the rubber insert placed over the
filling hole.
ELECTRODE THEORY
Electrode Operation
The Cupric Ion Electrode is composed of sulfides of copper and
other metals bonded into an epoxy or glass body. When an
electrode potential develops across the membrane, the membrane is
in contact with a solution containing cupric ions. The electrode
potential is measured against a constant reference potential,
using a standard pH/mV meter. The level of cupric ions,
corresponding to the measured potential, is described by the