3
Measurement (calibration)
1. Open the internal solution filler port.
2. If the amount of internal solution has decreased, fill up
the internal solution.
3. Wash the electrode with pure water (or deionized water)
and wipe it with filter paper or tissue paper, prior to every
immersion into standard/sample solution.
4. When there are air bubbles inside the responsive glass
membrane, stir it lightly to remove bubbles.
5. Immerse the responsive glass membrane and liquid
junction in the sample completely.
Make sure that the surface of the internal solution inside
the electrode is higher than the surface of the sample
solution.
6. Stir the electrode lightly to remove bubbles.
Note
Be sure to keep the internal solution filler port open during
measurement. If it is clogged with the solution, accurate
measurement cannot be performed. Wipe the solution with
cloth.
For calibration/measurement on pH meter, refer to the
instruction manual of pH meter.
Maintenance
Note
Do not use organic solvents (such as acetone or
tetrahydrofuran) or acid (above 1 mol/L) or alkaline (above 0.1
mol/L) cleaning solutions. Using such chemicals may damage
the body of the electrode or cause a decline in performance.
To maintain electrode performance, replace the internal
solution approximately every one or two months. (Refer
to "Preparation" (page 2).)
Dirt on the responsive glass membrane or liquid junction
by the sample may cause a decline in electrode
response and sensitivity or measurement error. If the
electrode is very dirty and cannot be washed clean
using pure water (or deionized water), perform the
following cleaning.
Cleaning of electrode
1. Open the internal solution filler port.
2. Immerse the responsive glass membrane and liquid
junction in cleaning agent according to the type of dirt for
approximately one hour until contamination is removed.
Refer to the instruction manual of cleaning agent.
The responsive glass membrane can also be cleaned by
wiping it with cotton gauze containing cleaning agent.
3. Rinse the electrode with pure water (or deionized water)
completely.
4. Replace the internal solution. (Refer to "Preparation"
Note
Be sure to perform calibration prior to measurement after
cleaning the electrode.
Tip
Applying pressure on the internal solution and exuding it from
liquid junction have an effect of stabilizing pH response.
Stop applying pressure when the internal solution begins to
exude. Applying excessive pressure may break the electrode.
Type of dirt
Cleaning agent
General
Diluted neutral cleaning agent
Oil
Alcohol, or diluted neutral cleaning agent
Inorganic substance
Electrode cleaner (model 220) or Hydrochloric
acid approximately 1 mol/L
Protein
Cleaning agent including protein-cutting enzyme
(model 250)
Liquid junction
Electrode cleaner (model 220)
Altered of glass,
Slow-response
Electrode cleaner (model 220)
