Characterization of an optical copper sensor based on N, N′-bis(salycilidene)-1,2-phenylenediamine

We prepared a copper selective optical chemical sensor based on N, N′-bis (salycilidene)-1,2-phenylenediamine (salophen) as ionophore. This proposed membrane works on the basis of a cation-exchange mechanism and shows a significant absorbance signal change on exposure to 0.05 mol l −1 acetate buffer solution of pH 5.5 containing copper ion. This optode membrane shows enhanced selectivity for Cu 2+ over other transition metal ions. The sensing membrane reversibly responses to copper ion over the wide range of 5.01 × 10 −8 to 6.32 × 10 −4 mol l −1 with a detection limit of 4.7 × 10 −8 mol l −1 (2.98 ppb) and response time of less than 3 min. This sensor has been used for determination of copper in some real samples containing potential interferents with satisfactory recovery.