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 Cu2+ over other transition metal ions. The sensing membrane reversibly responses to copper ion over the wide range of 5.01 x 10(-8) to 6.32 x 10(-4) mol l(-1) with a detection limit of 4.7 x 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. (c) 2005 Elsevier B.V. All rights reserved.