Application of chloride-selective microelectrodes to renal test dyes and other food or cosmetic dyes

The measurement of chloride activity was studied with Cl- -sensitive ion-exchanger microelectrodes (ISE) in calibrated test solutions stained with commonly used renal test dyes (e.g. Lissamine green SF) or other food or cosmetic dyes. Renal test dyes impair measurements of Cl- activity due to their anionic substitution and were found to increase electrode resistance. Cationic food dyes did not interfere with the Cl- reading of ISE although electrode resistances were increased, too.