Abstract
A PVC-based membrane electrode for lead ions based on hexathia-18-crown-6-tetraone as membrane carrier was prepared. The influence of membrane composition, pH of test solution and foreign ions on the electrode performance were investigated. The electrode showed a Nernstian response over a lead concentration range from 1.0 × 10-6 to 8.0 × 10-3 M at 25°C, and was found to be very selective, precise and usable within the pH range 3.0 - 6.0. The electrode was successfully used as an indicator electrode in potentiometric titration of lead ions and in direct determination of lead in water samples.