Determination of copper using porphyrin by cloud point extraction

A cloud point extraction procedure was presented for the preconcentration of copper(II) ion in aqueous samples. After complexation by 5,10,15,20-tetrakis(4-methoxyphenyl) porphyrin (TMPP), copper(II) ion was quantitatively recovered in Triton X-100 after loading to minicolumn containing cotton. 2.5 mL of 25 per cent THF acidified with 1.0 mol/L nitric acid was used as eluent for stripping the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The influence of analytical parameters including ligand, Triton X-100 and nitric acid concentration and volume, effect of polar solvent in desorption solution, stirring time, concentration of electrolyte optimized. The effect of the matrix ions on the recovery of copper ions was investigated. The obtained detection limit 4.3 ng/mL was sufficiently low for detecting copper in diverse samples. The enrichment factor of 5 with RSD of 2.1 per cent for copper was achieved. The applicability of the method was confirmed by the analysis of water samples. The interference effects of some anions and cations were also tested.