A Nanoparticle-based Solid-phase Extraction Followed by Flow Injection ICPOES to Determine some Heavy Metal Ions in Water Samples

Nanotechnology as a powerful platform for the 21st century technologies could substantially enhance environmental quality and sustainability through pollution prevention, treatment and remediation. In particular, application of magnetic nanoparticles (MNPs) technology to solve environmental problems had received considerable attention in recent years. Use of nanoparticles for sample preparation in chemical analysis is gaining research interest [1]. Compared with micrometer-sized particles used for solid-phase extraction (SPE), NPs offer a significantly higher surface area-to-volume ratio that promises much greater extraction capacity and efficiency [2]. Fe3O4 MNPs are superparamagnetic particles and they are attracted to a magnetic field but retain no residual magnetism after the field is removed. Superparamagnetic NPs can be easily collected by using an external magnetic field placed outside of the extraction container. This property makes them particularly suitable for sample preparation because no centrifugation or filtration of the sample is needed after the treatment.The aim of the present study was to develop a NP-based solid phase extraction (SPE) of some metal ions (Cd2+, Co+2, Cr3+, Ni2+, Pb2+ and Zn2+). The metal ions form very stable complexes with 1-(2-pyridilazo)-2-naphthol (PAN) and the formed complexes were adsorbed on the Fe3O4 MNPs in a batch extraction procedure. The extracted metal ions were determined simultaneously using a flow injection ICP-OES. To the best of our knowledge, Fe3O4 MNPs have not been employed previously for the extraction and concentration of the studied metal ions from aqueous samples