A potentiometric detector for following pH shifts in liquid chromatography

A potentiometric detector suitable for measurement of pH shifts caused by cation-exchange phenomena in reverse-phase liquid chromatography is described. A capillary flow-through glass pH electrode and a small reference electrode are included in a design that produces reliable results in the acid pH range. The detector is calibrated in the steady-state and dynamic modes with pH reference solutions in water and water-methanol mixtures.