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MI-411 and MI-413 MI-414
Needle
Micro-combination
Microelectrodes
Operating
Instructions |
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The
microelectrode is ready to use.
Carefully unwind the tape and remove
the probe from the protective glass
tube. The white translucent sleeve,
which covers the hole, should be
moved down the glass barrel slightly
to ventilate the reference chamber
and replaced after each use.
The use of a
separate Reference Electrode is not
required.
Calibration
The
electrode can be held by hand when
measuring pH. It has been
standardized in two (2) pH buffers.
Follow the procedure recommended by
the manufacturer of your pH meter
for calibration.
Optimum Response Time:
Optimum response time will be
obtained after the probe has been
exercised in two (2) buffer
solutions. Fill one beaker
with a pH 4.01 buffer or equivalent
and a second beaker with a pH 6.86
buffer or equivalent. Hold the
microelectrode and touch the pH 4
.01 buffer surface allowing 5
seconds for equilibration, and then
touch the pH 6.86 buffer surface in
the same manner. Do this
several times. It is not
necessary to rinse the probe with
distilled water because the
carry-over is negligible.
Handling
The
outer reference chamber of the
microelectrode can be refilled when
necessary with the 3 M
KCl solution, using the bulb
pipette. Hold the electrode at a 60
degree angle (approx.) and slowly
insert the tip into the fill hole of
the electrode.
Be careful
not to apply pressure against the
inner glass capillary tube.
Slowly fill the reference chamber.
If filling is done too quickly, air
may be trapped in the chamber
causing reference solution to squirt
out of the fill hole instead of
entering and filling the reference
chamber.
Cleaning
When using the
microelectrode in solutions
containing protein, it should be
soaked in an enzyme cleaning
solution such as Terg-a-zyme
(Alconox,
Inc.) or a
chromic/sulfuric acid glass cleaning
solution for a couple of minutes
after each use to remove the protein
from the glass and the reference
junction. This will prolong
the useful life of the
microelectrode.
Storage
Always clean the microelectrode
before storing:
Long-term (over 2 weeks):
Return the electrode to its original
container and prepare it in the same
condition in which you received it.
Usually this means simply moistening
the sponge located in the bottom of
the protective glass tube with pH 4
buffer.
Short-term: The
probe can be left in an acid pH
buffer solution (pH 4.01).
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