Selective Determination of Zn²⁺ Ion in Various Environmental, Biological and Medicinal Plant Samples Using a Novel Coated Graphite Electrode

Abstract

Novel Zn2+ ion‐selective PVC based coated graphite electrodes were fabricated using the ionophores N‐((1H‐indol‐3‐yl)methylene)thiazol‐2‐amine (I1), N‐((1H‐indol‐3‐yl)methyl)‐thiazol‐2‐amine (I2) and 1‐((1H‐indol‐3‐yl)methylene)urea (I3). Their potentiometric performance was examined in dependence of the addition of plasticizers and anion excluders and compared. It is found that the coated graphite electrode with the composition I1:KTpClPB:o‐NPOE:PVC=9 : 1.5 : 51 : 38.5 is the best with respect to the wide working concentration range (4.2×10−8–1.0×10−1 mol L−1), low detection limit (1.6×10−8 mol L−1) and wide pH range of 3.0–8.0. The proposed electrode was successfully applied to quantify Zn2+ in various environmental, biological and medicinal plant samples and used as indicator electrode.