Frequently Asked Questions about the pH Electrodes
1. How long is the service life of pH electrodes?
The expected lifespan of a properly maintained pH electrode is around one to three years. The factors that shorten the service life of electrodes include high temperature and measurement under extreme pH conditions, even properly maintained and stored electrodes can have a shortened service life. If the electrode performance begins to decline, the pH sensitive glass film can be regenerated and the electrode performance can be restored to its original level.
2. How to choose the correct pH electrode?
It is important to choose the correct pH electrode for each application in order to ensure optimal pH measurement results. The most important sample standards are: chemical composition, uniformity, temperature, process pressure, pH range, and container size (length and width limitations). For non-aqueous, low conductivity, protein rich, and viscous measurement media, electrode selection is particularly important. In these samples, universal glass electrodes are susceptible to various influences, leading to measurement errors. The response time and accuracy of electrodes depend on many factors. Compared to measurements taken at room temperature for neutral pH aqueous solutions, measurements taken under extreme pH and temperature or low conductivity conditions have longer response times.
3. How to maintain/clean electrodes?
Routine maintenance is crucial for extending the lifespan of pH electrodes. When the liquid level may be lower than the liquid level of the sample solution, it is necessary to add electrolyte to the electrode that can be filled with electrolyte. Maintenance can prevent the sample from flowing back into the electrode. All reference electrolytes should be replaced regularly (approximately once a month). This ensures that the electrolyte is fresh and will not crystallize during the measurement process due to evaporation from the open filling port. It is very important to ensure that no bubbles are generated inside the electrode, especially near the liquid network. If this situation occurs, the measurement results will become unstable. To eliminate bubbles, gently shake the electrode in a manner similar to shaking a thermometer.
To clean the electrode, rinse it with deionized water after each measurement, but do not wipe it with a tissue. The paper towel surface may scratch and damage the pH sensitive glass film, wipe off the gel layer, and generate static charges on the electrode. This type of static charge can cause the measurement signal to become very unstable. After being contaminated by certain samples, special cleaning operations may be required.
