A simple and fast approach for solid phase extraction is herein described, and used to determine trace amounts of Pb2+ and Cu2+ metal ions. The solid phase support is sodium dodecyl sulfate (SDS)-coated γ-alumina modified with bis(2-hydroxy acetophenone)-1,6-hexanediimine (BHAH) ligand. The adsorbed ions were stripped from the solid phase by 6 mL of 4 M nitric acid as eluent. The eluting solution was analyzed by flame atomic absorption spectrometry (FAAS). The sorption recovery of metal ions was investigated with regard to the effects of pH, amount of ligand, γ-alumina and surfactant and the amount and type of eluent. Complexation of BHAH with Pb2+ or Cu2+ ions was examined via spectrophotometry using the HypSpec program. The detection limit for Cu2+ was 7.9 µg L-1 with a relative standard deviation of 1.67%, while that for Pb2+ was 6.4 µg L-1 with a relative standard deviation of 1.64%. A preconcentration factor of 100 was achieved for these ions. The method was successfully applied to determine analyte concentrations in samples of liver, parsley, cabbage, and water.

A very simple cloud point extraction (CPE) methodology for the preconcentration of trace amounts of silver and magnesium as a prior step for their determination by flame atomic absorption spectrometry (FAAS) has been developed. The method is based on the extraction of silver and magnesium at pH 10 by using non-ionic surfactant Triton X-114 and 4 methyl-3-((1-H-Indol-3-iyl) (phenyl) methyl)) -1-H-Indol (MPBIM) as a complexing agent. Several important variables that affect the CPE efficiency and FAAS signal were investigated and optimized. The calibration curves, using the preconcentration system, were linear in the range of 0.007-0.200 μg mL-1 with a correlation coefficient of 0.999. The lower limits of detection (3s) obtained in the optimal conditions were 1.47 ng mL-1 and 3.00 ng mL-1 for Mg²+ and Ag+ ions, respectively. The relative standard deviation for five replicate determinations of magnesium and silver at 0.133 μg mL-1 concentration level, were 1.17 and 0.97, respectively. The proposed method was successfully applied to the ultra-trace determination of silver and magnesium in various water samples, blood serum, urine, and radiology film samples.