Use of Fe₃O₄ Magnetic Nanoparticles Coated with Polythiophene for Simultaneous Preconcentration of Cu (II), Co (II), Cd (II), Ni (II) and Zn(II) Ions Prior to their Determination by MIS-FAAS

A multielement preconcentration procedure based Fe3O4 magnetic nanoparticles coated with polythiophene(Fe3O4@ PTh MNPs) as a solid phase was reported for Cu(II), Co(II), Cd(II), Ni(II) and Zn(II) ions. Following the preconcentration, the ions were determined by microsample injection system-flame atomic absorption spectrometer (MIS-FAAS). The effect of sample pH, type and volume of eluent, sample volume, extraction time, amount of adsorbent and interfering ions were optimized. The analytes were preconcentrated from 75 to 150 mL of sample solutions buffered to pH 7. The eluent was 1 mL of 1 mol L-1 HNO3 solution. Under optimum conditions, the limits of detection for the analyte ions varied from 1 to 10 mu g L-1. The adsorption capacities of Fe3O4@PTh was in the range of 2.85 to 9.76 mg g(-1). The method was validated by analysis of the certified reference materials. The relative errors and standard deviations were lower than 5%. The developed procedure was applied to various water, soil and some vegetable samples.