A disposable electrode based on zeolite–polymer membranes for potentiometric titrations of ionic surfactants

A planar all-solid-state electrode for the titrimetric analysis of ionic surfactants has been developed and characterised. The electrode is fabricated by lamination of suitable electrode structures that are sandwiched between flexible plastic foils. The zeolite–polymer membrane containing 50% (w/w) zeolite of the faujasite type is cast onto an exposed gold film surface to form the surfactant-sensitive electrode. ry fast potentiometric response of the sensor can be exploited for potentiometric titrations of surfactants. Without any further pre-treatment, reproducible and well-defined titration curves are obtained for the titrimetric analysis of anionic surfactants using a cationic surfactant and vice versa. According to the fabrication strategy applied, the developed devices have the character of disposable electrodes. The electrode assembly exhibits shelf-lives longer than 3 months under room temperature and dry conditions. The practical utility of the disposable all-solid-state electrodes is demonstrated in terms of titrimetric determinations of anionic surfactants in commercial detergents.