Novel potentiometric sensor for selective monitoring of Ce3 + ion in environmental samples

Abstract

Novel ligand 1,1′-(pyridine-2,6-diyl)bis(3-(1H-pyrrol-2-yl)prop-2-en-1-one) (L) was synthesised and explored as ion carrier for the selective monitoring of Ce3+ ion in various samples. Spectrophotometric and conductometric studies reveals high affinity of L towards Ce3+ ion and therefore, L was used in the fabrication of poly (vinyl chloride) based membrane sensor of coated graphite electrode (CGE) and coated pyrolytic graphite electrode (CPGE). Best performance was observed with the optimized membrane composition of L: PVC:o-NPOE:NaTPB::7:31:59:3 (w/w, mg). The CPGE exhibits wide working concentration range of (1.9×10−8–1.0×10−1molL−1) and low detection limit of 5.0×10−9molL−1 with Nernstian slope of 19.4±0.2mV−1 decade of activity. The sensor is independent of pH in the pH range of 3.0–8.5 and exhibited fast response time of 9s. The sensor can work satisfactorily in partially non-aqueous media of water-acetonitrile and water-ethanol (30%, v/v) and could tolerate about 20% (v/v) of water-methanol contents. The applicability of the sensor is illustrated by determining Ce3+ ion in real samples and as an indicator electrode in the potentiometric titration of Ce3+ ion with oxalate and fluoride ions.