Thiocyanate ion selective electrode based on bis(N-3-methylphenyl salicylidenaminato)copper(II) ionophore

In this work a PVC membrane electrode based on bis(N-3-methyl phenyl salicylidenaminato)copper(II) as ionophore was prepared. The electrode was tested by inorganic anions and showed good selectivity for thiocyanate ion. This sensor showed Nerstian behavior with a slope of a -59.3 mV per decade at 25 degrees C. The proposed electrode exhibited a wide linear range from 1.0 x 10(-6) mol/L to 1.0 x 10(-1) mol/L with a detection limit of 5.0 x 10(-7) mol/L. The electrode response was independent of pH in the range of 4.0-10.0. The response time is about 9-21 s, and the electrode can be used for over 60 days without considerable deterioration. The prepared sensor was applied as an indicator electrode in potentiometric titration of SCN- with Ag+ ion and to determine the thiocyanate in samples of urine and saliva. (C) 2014 Published by Elsevier B.V. on behalf of Chinese Chemical Society.