Solid phase extraction of copper traces using poly(styrene-divinylbenzene) membrane disks modified with pyridoxal salicyloylhydrazone in water samples

A simple technique for the isolation, concentration and matrix simplification of Cu(II) ion in natural waters is proposed. This method has been developed using poly(styrene-divinylbenzene) membrane disks modified with the synthesized ligand pyridoxal salicyloylhydrazone (PSH). The retained ions on the disks were eluted with 10 mL 1 mol L−1 HNO3 and measured by flame atomic absorption spectrometry at 324.8 nm. The influence of pH, amount of ligand, type and amount of eluent for the stripping of copper ion from the membrane over extraction efficiency were evaluated. Extraction efficiencies >99% were obtained by elution of the disks with minimal amount of solvent with a preconcentration factor up to 100. The precision of the method for 10 replicate measurements of aqueous solutions containing 40 μg L−1 Cu(II) was 1.5% at significance level of 95%. The breakthrough volume for 5 μg of Cu(II) was found to be 1000 mL and the detection limit of the method was 4 ng L−1 of metal ion. The present method was successfully applied to the extraction and determination of copper in lake and sea waters.