PVC-based 1,3,5-trithiane sensor for cerium(III) ions

A PVC membrane sensor for cerium(III) ions based on 1,3,5-trithiane as memb rane carrier was prepared. The sensor has a linear dynamic range of 1.0 x 1 0(-1)-5.0 x 10(-5) M, with a Nernstian slope of 19.4 +/- 0.4 mV decade(-1), and a detection limit 3.0 x 10(-5) M. It has a fast response time of <15 s and can be used for at least 5 months without any considerable divergence in potentials. The proposed sensor revealed comparatively good selectivitie s with respect to alkali, alkaline earth, and some transition and heavy met al ions and could be used in a pH range of 5.0-8.0. It was used as an indic ator electrode in potentiometric titration of oxalate and fluoride ions and in determination of F- ion in some mouth wash preparations.