Silver(I)-selective membrane potentiometric sensor based on two recently synthesized ionophores containing calix[4]arene

Abstract

Two new PVC membrane electrodes that are highly selective to Ag(I) ions were prepared using (L1) calyx[4]arene (L2) as two suitable neutral carriers. The silver(I) ion selective electrodes exhibit a good response for silver ion over a wide concentration range of 1.0 × 10−1 to 4.2 × 10−6 M (L1) and 1.0 × 10−1 to 6.5 × 10−6 M (L2) with a Nernstian slope of 60 mV per decade (L1) and 58 mV per decade (L2) at 25°C, and was found to be very selective, precise, and usable within the pH range 4.0–8.0. They have a response time of <15 s and can be used for at least 3 months without any measurable divergence in potential. The proposed sensors show a fairly good discriminating ability towards Ag+ ion in comparison to some hard and soft metal ions. The electrodes were used as indicator electrodes in the potentiometric titration of silver ion and in the determination of Ag+ in photographic emulsion and radiographic and photographic films.