Application of Modified Magnetite Nanoparticles as a New Sorbent for Separation/Preconcentration of Mercury(II) Trace Amounts and its Determination by Cold Vapor Atomic Absorption Spectrometry

A new, simple, fast and reliable method has been developed to separation/preconcentration of trace amounts of mercury ions using dithizone/sodium dodecyl sulfate-immobilized on alumina-coated magnetite nanoparticles (DTZ/SDS-ACMNPs) and its determination by cold vapor atomic absorption spectrometry (CVAAS). This method avoided the time-consuming column-passing process of loading large volume samples in traditional solid phase extraction (SPE) through the rapid isolation of DTZ/SDS-ACMNPs with an adscititious magnet. Under the optimal experimental conditions, the enrichment factor, detection limit, linear range and relative standard deviation (RSD) of Hg(II) ions were 250 (for 500 mL of sample solution), 0.058 mu g mL(-1), 0.2-80.0 mu g mL(-1) and 3.55% (for 5.0 mu g n=10), respectively. The adsorbed mercury ions were quantitatively eluted by 2.0 mL of 0.4 mol L-1 HBr solution. The presented procedure was successfully applied for determination of mercury content in the different samples of water and blood.