Design of a selective and sensitive PVC-membrane potentiometric sensor for strontium ion based on 1,10-diaza-5,6-benzo-4,7-dioxacyclohexadecane-2,9-dione as a neutral ionophore

A novel PVC membrane sensor for the Sr2+ ion based on 1,10-diaza-5,6-benzo-4,7-dioxacyclohexadecane-2,9-dione has been prepared. The sensor possesses a Nernstian slope of 30.0 +/- 0.6 mV decade(-1) over a wide linear concentration range of 1.6 x 10(-6)-3.0 x 10(-3) M with a detection limit of 6.3 x 10(-7) M. It has a fast response time of <15 s and can be used for at least two months without any considerable divergence in potential. The potentiometric response is independent of the pH of test solution in the pH range 4.3-9.4. The proposed electrode shows good selectivities over a variety of alkali, alkaline earth, and transition metal ions.