Micelle Mediated Methodology for the Determination of Heavy Metals in Real Samples by Flame Atomic Absorption Spectrometry

A simple and sensitive method is described for the pre-concentration by cloud point extraction followed by atomic absorption spectrometric determination of nickel, lead, zinc and copper ions in real samples. At a solution pH of 7.0, 2-amino-5-mercapto-1, 3, 5 -thiadiazole (AMTD) and TritonX-114 were used as hydrophobic ligand and non-ionic surfactant. The adopted concentrations for AMTD, Triton X-114 and HNO3, bath temperature, centrifuge rate and time were optimized. Detection limits (3SDb/m) of 1.4, 1.6, 1.7 and 1.5 ng mL-1 for Ni2+ , Pb2+, Zn2+ and Cu2+ along with enrichment factors of 29 for these ions were achieved. The high efficiency of cloud point extraction to carry out the determination of analytes in complex matrices was demonstrated. The proposed procedure was applied to the analysis of biological, industrial, natural and waste water, soil and blood samples.