How to measure pHT in biological experiments

Research on ocean acidification requires following best practices. The OA-ICC contributes to the development of teaching material for the implementation of simplified methodologies for laboratories with limited finances or infrastructure.

Authors: Sanja Grđan, University of Dubrovnik & Sam Dupont, University of Gothenburg

Translation: Celeste Sánchez Noguera (Spanish) and Sam Dupont (French)

Description: Measuring pH in seawater using a glass electrode is not trivial and requires TRIS buffer. TRIS buffers are commercially available from Dr. Andrew Dickson’s laboratory at the Scripps Institution of Oceanography, California. However, access to this buffer can be difficult due to a continuously increasing demand as well as costs including shipping, customs fees, and taxes, making them less available for countries and laboratory with limited funds.

A simplified buffer preparation method is described in Paulsen & Dickson (2020) making the use of TRIS buffers available to a wider range of researchers.

The aim of this document and associated material (xls sheets and videos) is to help experimentalists entering the field of ocean acidification to make their own TRIS buffer, calibrate their glass electrodes for pH measurement on the total scale, take water samples and calculate pH on the total scale (pH_T).

English Language Materials

French Language Materials

Spanish Language Materials

IAEA, 6 July 2022. More information.

Ocean Acidification