A copper-selective electrode based on bis(acetylacetone)propylenediimine

The potentiometric response characteristics of Cu²⁺-selective electrodes based on bis(acetylacetone)propylenediimine (I) combined with anion localizing agent (sodium tetraphenyl borate (NaTPB)) and solvent mediators (dibutyl butyl phosphonate (DBBP), tri-n-butyl phosphate (TBP) and chloronaphthalene (CN)) were investigated. The best results for Cu²⁺ sensing was obtained for the electrode membrane containing PVC, I, DBBP and NaTPB in composition 5:100:200:6 (I:PVC:DBBP:NaTPB) (w/w; mg), where the electrode had a Nernstian response (30.0 mV/decade) to Cu²⁺ within the concentration range 1.0 × 10⁻⁵ to 1.0 × 10⁻¹ M and detection limit of 0.5 ppm. The operational pH range of the electrode was 3.3-7.0. Selectivity characteristic of the proposed electrode was also assessed by calculating using fixed interference method matched potential method. The sensor has been successfully used in the potentiometric titration of copper ions with EDTA.