Performance evaluation of copper ion selective electrode based on cyanocopolymers

A copper(II) ion selective electrode based on copper(II) salicylaniline Schiffʹs base complex in styrene-co-acrylonitrile copolymer (SAN) has been developed. The SAN-based membrane electrode containing copper(II)–Schiffʹs base complex, dioctylphthalate as plasticizer and sodium tetraphenylborate as an anion excluder exhibited a linear response with a Nerstian slope of 30 mV decade−1 within the concentration range of 10−6–10−2 mol dm−3 of Cu2+ ions. The prepared electrode has an average response time of 15 s to achieve 95% steady potential for Cu2+ concentration ranging from 10−4 to 10−2 mol dm−3. The electrode has shown a detection limit of 10−7 mol dm−3 of Cu2+ ion with an average lifetime of 6 months. The selectivity of electrode for Cu2+ ion has been found to be better in comparison to other various interfering ions. The electrode is suitable for use within the pH range of 2.0–7.0 at 1.0×10−3 mol dm−3 of Cu2+ ion. The prepared electrode can be used successfully as an indicator electrode for the potentiometric titration of the Cu2+ ion using EDTA.