title: The first use of a Rh(III) complex as a novel ionophore for thiocyanate-selective polymeric membrane electrodes.
abstract: The feasibility of a newly synthesized Rh(III) complex, Rh[(trpy)(bpy)Cl](PF(6))(2), as a novel ionophore for the preparation of anion-selective polymeric membrane electrodes was tested. The ionophore exhibited anti-Hofmeister behavior with enhanced potentiometric selectivity toward thiocyanate ion compared to other anions. The influence of some experimental parameters such as membrane composition, nature and amount of plasticizer and additive and concentration of internal solution on the potential response of the SCN(-) sensor were investigated. The electrode exhibits a Nernstian response for SCN(-) over a wide concentration range (1.0 x 10(-5) to 1.0 x 10(-1)M) with a slope -58.7 +/- 0.5mV per decade and a detection limit of 4.0 x 10(-6)M (0.23ppm). It could be used in a pH range of 3.0-8.0 and has a fast response time of about 15s. The proposed sensor was used for the determination of thiocyanate ions in real samples such as urine and saliva of smokers and nonsmokers and, as an indicator electrode, in potentiometric titrations of SCN(-) ion.
authors.affiliation: Department of Chemistry, Razi University, Kermanshah, Iran.
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Shamsipur
authors.forename: Sohrab
authors.initials: S
authors.lastname: Ershad
authors.forename: Naser
authors.initials: N
authors.lastname: Samadi
authors.forename: Ali Reza
authors.initials: AR
authors.lastname: Rezvani
authors.forename: Hasan
authors.initials: H
authors.lastname: Haddadzadeh