Synthesis of a New Calix[4]Arene and Its Application in Construction of a Highly Selective Silver Ion-Selective Membrane Electrode

Abstract

A PVC membrane sensor for Ag (I) ions has been prepared. The membrane has 5, 11, 17, 23-tetra-tert-butyl-25-(3-N, N-diethyldithio carbamoylpropoxy)-26,27,28-tris-propoxy calix[4]arene (CAD) as a carrier. It was found that the sensor exhibits a Nernstian response for Ag+ ions over a wide concentration range (10−2–10−6 M). Additionally, it illustrates a fast response time (about 5 seconds), and it can be used for at least 2 months without any considerable divergence in potentials. The nature of the plasticizer, the additive, the concentration of internal solutions in the electrodes, and the composition of the membrane were investigated. Furthermore, the suggested membrane electrode revealed good selectivities for Ag+ over a variety of other metal cations, and it could be used in the pH range of 3.0–7.0. Eventually, it was successfully applied as an indicator electrode for the potentiometric titration of Ag+ ion with NaCl.