Meaning
Slow changes in the output signal of a sensing probe occur over time even when the sample concentration remains constant. Persistent potentiometric electrode drift results in a shifting baseline that compromises the accuracy of acid or base titrations. The phenomenon stops being a factor once the electrode is cleaned or the internal electrolyte is replenished.
Signal Instability
Build-up of polymer residue or surfactants on the glass membrane slows the ion exchange process. Because potentiometric electrode drift introduces a time-dependent error, the titration endpoint may be overshot or undershot. This leads to inconsistent results between laboratory shifts even when testing the same resin batch.
Calibration Frequency
Frequent standardization against known buffers compensates for the changing slope of the sensor response. Regular monitoring of potentiometric electrode drift identifies the moment when a probe is no longer fit for purpose. Maintenance involves soaking the tip in a rejuvenation solution to clear the pores.
This ensures that the millivolt readings remain tethered to the actual pH or ion concentration of the solvent. Proper storage of the probe in a dedicated electrode solution prevents the drying of the sensing layer.
Sensor Integrity
Neglecting the health of the probe leads to retesting and production delays. Controlled potentiometric electrode drift preserves data quality.
