Dithizone modified magnetic nanoparticles for fast and selective solid phase extraction of trace elements in environmental and biological samples prior to their determination by ICP-OES

► We prepared dithizone modified silica-coated magnetic Fe3O4 nanoparticles. ► A method of magnetic SPE-ICP-OES was proposed for trace heavy metal analysis. ► The developed method is simple, highly selective and sensitive. ► It is suitable for the analysis of samples with large volume and complex matrix. ► The adsorption mechanism was investigated by FT-IR and XPS.