Hg2+-selective membrane potentiometric sensor based on a recently synthesized mercapto compound

A new PVC membrane electrode for Hg(II) ion based on a recently synthesized mercapto compound of 2-benzoylamino-3-(4-chloro-phenyl)-thioacrylic acid S-(2-mercapto-4-methyl-phenyl) ester is reported. The electrode exhibits a Nernstian response for Hg2+ ions over a wide concentration range (2.0 x 10(-7)- 3.0 x 10(-2) M) with a slope of 29 (+/- 1). The limit of detection is 5.0 x 10(-8) M. The proposed sensor revealed good selectivities over a wide variety of other cations include hard and soft metals. This electrode could be used in a pH range of 1.0-4.0. It was used as an indicator electrode in potentiometric titration of mercury(II) ions and can be used in the direct determination of Hg2+ in aqueous solutions.