Solid phase extraction of trace amounts of Pb(II) in opium, heroin, lipstick, plants and water samples using modified magnetite nanoparticles prior to its atomic absorption determination

A new, simple, fast and reliable solid-phase extraction method has been developed for separation/preconcentration of trace amounts of Pb(II) using dithizone/sodium dodecyl sulfate-immobilized on alumina-coated magnetite nanoparticles, and its determination by flame atomic absorption spectrometry (FAAS) and graphite furnace atomic absorption spectrometry (GFAAS) after eluting with 4.0 mol L −1 HNO 3 . Optimal experimental conditions including pH, sample volume, eluent concentration and volume, and co-existing ions have been studied and established. Under the optimal experimental conditions, the preconcentration factor, detection limit, linear range and relative standard deviation of Pb(II) using FAAS technique were 280 (for 560 mL of sample solution), 0.28 ng mL −1 , 1.4–70 ng mL −1 and 4.6% (for 10 ng mL −1 , n = 10), respectively. These analytical parameters using GFAAS technique were 300 (for 600 mL of sample solution), 0.002 ng mL −1 , 0.006–13.2 ng mL −1 and 3.1% (for 5 ng mL −1 , n = 10), respectively. The presented procedure was successfully applied for determination of Pb(II) content in opium, heroin, lipstick, plants and water samples.