A Novel PVC Membrane Sensor for Selective Determination of Cerium(III) Ions

Abstract

A PVC membrane of azomethine of piperonylidine-4-[2.2]paracyclophanylamine reveals a Nernstian potentiometric response (with slope of 19.3 ± 0.3 mV/decade) for Ce(III) over a wide concentration range (10⁻¹−2.5 × 10⁻⁵ mol L⁻¹). The potential of this electrode is independent of pH in the range of 4.5–8.0. It has a fast response time of 30 s and can be used for a period of two months with good reproducibility. The detection limit of this membrane electrode is 1.2 × 10⁻⁵ mol L⁻¹. The nature of the azomethine compound and its cerium(III) complex is examined using Fourier-transform infrared analysis, elemental analysis, and X-ray fluorescence techniques. This sensor exhibits a very good selectivities for Ce(III) over a wide variety of metal ions. The proposed sensor has been used as an indicator electrode in the potentiometric titration of carbonate and oxalate ions and in determination of acetyl salicylate content in some drugs.

Keywords:

• Cerium sensor
• Ion-selective electrode
• PVC membrane
• Potentiometric titrations