Before first use: Soak in 100ppm sodium calibration standard for 24 hours to condition the probe
With use (submersion in the liquids under test) the response time will become slow and it might be difficult to calibrate. If this occurs the probe needs to be cleaned.
General Cleaning: Rinse electrodes in deionized water and gently remove any sample particles with a lab wipe. Soak in 100 ppm calibration standard.
Oil/Grease Films: Wash sensing electrode bulb in a dilute solution of Dawn detergent and warm water. Rinse electrode tip with distilled water and soak the electrode in 100 ppm calibration standard.
Protein Deposits: Dissolve protein deposits by immersing the electrode in a 1% pepsin solution with a background of 0.1M HCl for five minutes, followed by thorough rinsing with distilled water and soaking in 100 ppm calibration standard.
After any of these special cleaning procedures, the reference chamber must be drained and refilled. Soaking overnight in 100 ppm calibration standard is recommended. If these steps fail to restore normal electrode response, replacing the electrodes is required.
100 ppm Sodium standard: