Determination of Pb 2+ ion in water samples by CPE-FAAS using erythrosine as complexing agent

A cloud point extraction procedure was presented for the preconcentration of Pb 2+ ion in various water samples. Pb 2+ ion after complexation with Erythrosine, quantitatively extracted in Triton X-114. After centrifugation, the surfactant-rich phase was dissolved in acidified methanol prior to its analysis by flame atomic absorption spectrometry (FAAS). The influence of analytical parameters including ligand, Triton X-114, bath temperature, heating time, centrifuge rate and time were optimized. The effect of the matrix ion on the recovery of Pb 2+ ion was investigated. The detection limit (3S.D.b/m, n=5) of 0.012 µg mL −1 along with preconcentration factor of 30 and enrichment factor of 15.07 with R.S.D. of 2.68% was achieved. The proposed procedure was applied to the analysis of various water samples.