Determination of Trace Amounts of Copper (II) by Selective PVC Membrane Electrodes

A simple and fast method for determination of trace amounts of copper (II) ions was developed usingsynthesized Schiff base 2-propylpiperidine-l-carbodithioate and explored as ionophore for preparingof PVC-based membrane sensors selective to the copper (Cu2+) ion. Potentiometric investigationindicated high affinity of these receptors for copper ion. The best performance was shown by themembrane composition (w/w) ofionophore containing: 1 mg, PVC: 30 mg, DOP: 69 mg. KTpCIPB as additive was added 50 mol % relative to the ionophore in 2 ml THF. The proposed sensor s detectionlimit is 5.0x10^-7 M over pH 4 at room temperature (Nemstian slope 30.89 mV/dec.) with a response time of 15 seconds with good selectivity to copper ion over a number of interfering cations.