Mercurated polystyrene as a sensor for anionic surfactants in ion-selective polymeric membrane electrodes

Mercurated polystyrene (R–Hg–Ac) was employed as a sensor in a membrane electrode sensitive to anionic surfactants. A Nernstian dependence over the concentration range of sodium dodecyl sulphate of from 1 × 10–3 to 1 × 10–7M and a high selectivity for anionic surfactants relative to inorganic anions were found for the electrode. Moreover, the electrode shows interesting properties towards hydroxyl ions. The electrode may find application in the analysis of surfactants, as an indicator electrode in the potentiometric titration of both cationic and anionic surfactants and in the physico-chemical studies of surfactant solutions.