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Performance of tetraethylthiuram disulphide (TETDS) as a carrier of silver ion across a polymeric inclusion membrane has been studied. This compound is also used as an ionophore in coated-wire ion-selective electrode for silver ion determination. Fundamental parameters like ion carrier concentration in the membrane phase and thiosulphate concentration in strip phase were also studied to see their effect on the transport of silver ions. The efficiency of silver transport in the presence of some interfering ions was investigated. The coated-wire electrode gave a Nernstian behavior in the activity range 5 × 10 −6 to 1 × 10 −1 M. The ion-selective electrode exhibits high selectivity towards some alkali, alkaline earth and transition metal ions. The electrode was used as an indicator electrode in titrations of I − , Br − and Cl − with Ag + ion.

A liquid membrane based Zn2+ ion selective electrode containing N,N′-Bis(2-dimethylaminoethyl)-N,N′-dimethyl-9,10 anthracenedimethanamine (Bis(TMEDA) anthracene) (I) as ionophore has been prepared and characterized. The membrane comprises of PVC, ionophore and plasticizer in the ratio of 33:2:65, respectively. It showed the best response in terms of detection limit (1.5 × 10− 6 M) and working concentration range (1.0 × 10− 5 M to 1.0 × 10− 1 M) with Nernstian response towards Zn2+ ions. The electrode responds within 15 s of coming in contact with the solution. The potential response remains almost unchanged over a pH range of 3.0 to 7.5. The electrode can be used for at least 3 months without any considerable alteration in its response behavior. The proposed electrode revealed good selectivity towards Zn2+ ions over a number of alkali, alkaline earth, transition metals and some other heavy metal ions. The electrode has been used as an indicator electrode in the potentiometric titration of Zn2+ with EDTA. The proposed electrode also detected Zn2+ ions from real life samples.

A new inorganic ion exchanger, zirconium (IV) antimonoarsenate has been synthesized at different pH values. An amorphous sample prepared at pH 1 having an ion-exchange capacity of 0.40 meq/g was selected for further studies. The material is characterized using various analytical techniques, like XRD, IR, TGA and SEM, in addition to the ion-exchange capacity and distribution coefficient ( K d ) studies. Further the exchanger has been used as an electro-active material for the determination of Cerium (III) ions with epoxy resin, PVC and polystyrene as binding materials. A membrane having a composition: ZrSbAs (50%) and polystyrene (50%) gives the best performance. It works well over a wide Ce (III) ion-concentration range of 5 × 10 −5 –1 × 10 −1 M with a super-Nernstian slope of 52.0 mV/decade. It has a fast response time of 10 s and has an average lifetime of four months. The proposed sensor shows a good selectivity for cerium (III) ions with respect to alkali, alkaline earth, some transition and rare earth metal ions that are normally present along with cerium in its ores. The electrode has also been used as an indicator electrode in potentiometric titrations of Ce (III) ions against oxalic acid.

New PVC membrane ion selective electrodes based on 1,3,5-Tris(8-quinolinoxymethyl)-2,4,6-trimethylbenzene (MO8HQ) are reported. The basic sensing material belongs to the group of tripodal ionophores. Also their derivatives prepared by placing suitable substitutents at fifth position of 8-oxine moiety, i.e, 1,3,5-Tris(5-chloro-8-quinolinoxymethyl)-2,4,6-trimethylbenzene (5CHQ), 1,3,5-Tris(5-benzoyl-8-quinolinoxymethyl)-2,4,6-trimethylbenzene (5BHQ) and 1,3,5-Tris[(5-phenylhydroxymethylene)-8-quinolinoxymethyl]-2,4,6-trimethylbenzene (HYD-8HQ) ionophores have also been used to make copper-selective membrane electrodes. Among all the four electrodes, MO8HQ and HYD-8HQ ionophores based electrodes show excellent response towards Cu (II) ions. The electrodes having composition 33% PVC, 4% MO8HQ and 63% dibutyl phthalate (DBP) and 33% PVC, 6% HYD-8HQ, 63% dibutyl phthalate (DBP) exhibit a good Nernstian response to Cu (II) ions in the range of 1.0 x 10(-6) to 1 x 10(-1) M. The electrode shows a reasonably fast response time of 15 s. The effect of pH and electrode response is also reported. It shows good selectivity for Cu (II) ions in comparison to heavy metal ions, transition metal ions and for alkali and alkaline earth metal ions. The electrode response and selectivity remains unchanged for at least 5 months. The electrode can be used as an indicator electrode in the potentiometric titration of Cu (II) ions with EDTA.

A new ion-selective electrode (ISE) based on dicyclohexano-18-crown-6 (DC18C6) as a neutral carrier is developed for lanthanum(III) ions. The electrode comprises of dicyclohexano-18-crown-6 (6%), PVC (33%), and ortho-nitrophenyl octyl ether (o-NPOE) (61%). The electrode shows a linear dynamic response in the concentration range of 10−6 to 10−1 M with a Nernstian slope of 19 mV per decade and a detection limit as 5×10−7 M. It has a response time of