Successive determination of Na + , Cl - , and H + activities on the skin surface with ion-selective electrodes.

A method is described for the rapid sequential measurement of Na, Cl-, and Hactivities on the skin surface with ion-selective electrodes. Rationales are given for details of technique such as temperature control, use of a conducting bridge, pH-dependence of sodium electrode performance, and the uniform electrode setting for all tests. Data on reproducibility document the precision of the method when applied to measurements on the skin surface. Reasons are given why Na and Clactivity measurements on the skin require a different design and interpretation than skin pH determinations.