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Research Use Only

pH

Measures the pH of the prepared solution potentiometrically with a calibrated glass electrode.

Method
pH meter
Turnaround
5 business days from sample receipt

What it determines

A glass electrode develops a voltage across its membrane in proportion to the difference in hydrogen ion activity between the sample and an internal reference solution. The meter reads that voltage against a reference electrode and converts it to pH units.

The electrode is calibrated with standard buffers bracketing the expected range immediately before the measurement, which sets the slope and offset used in that conversion. Temperature affects both the electrode response and the pH of the solution itself, so the reading is taken with temperature compensation and the temperature is recorded.

Practical notes

  • Preparation drives the value. Concentration, diluent, and the presence of any buffer all move it.
  • Dissolved carbon dioxide shifts the pH of weakly buffered solutions during handling, and readings are taken promptly after preparation.
  • Small-volume samples are accommodated with a micro electrode, arranged at intake.

Sample intake instructions, including the quantity required, are sent once we know which assays you want.