Instruction Manual
CyberScan pH 11 / 110
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rejuvenate it. (See section 11.4 on Rejuvenation Procedure).
11.2 Electrode
Cleaning
Electrodes that are mechanically intact can be restored to normal performance by
one or combination of the following procedures.
a) Salt deposits:
Dissolve the deposit by immersing the electrode in tap water for ten to fifteen
minutes. Then thoroughly rinse with deionised water.
b) Oil / Grease Films:
Wash electrode pH bulb in a little detergent and water. Rinse electrode tip with
deionised water.
c) Clogged Reference Junction:
Heat a dilute KCl solution to 60-80 °C. Place the sensing portion of the pH
electrode into the heated KCl solution for approximately 10 minutes. Allow the
electrode to cool while immersed in some unheated KCl solution.
d) Protein Deposits:
Prepare a 1% pepsin solution in 0.1M HCl. Allow the electrode to stand in this
solution for five to ten minutes. Rinse the electrode with deionised water.
11.3 Electrode
Activation
Generally, if the procedure of storage and maintenance had been closely followed,
the electrode can be used immediately. However, should the electrode response
become sluggish, it may be possible that the bulb has dehydrated. The bulb can be
re-hydrated by immersing the electrode in an ideal storage solution (e.g. buffer pH 4
solution) for 10 to 30 minutes. If this fails, the electrode may require re-activation.
At no time should one touch or rub the glass bulb as this causes the build-up of
electrostatic charge.
If the above procedure does not re-activate the electrode to acceptable status, try
rejuvenating the electrode by following the procedure outlined below.