Comparative study for separation, preconcentration and determination of some trace elements using flame atomic absorption spectrometry by magnetic methacrylamide/divinylbenzene and magnetic methacrylamide/divinylbenzene graphene oxide composites

Two new magnetic solid-phase extraction (MSPE) procedures were as developed for the determination of trace amounts for Cd(II), Ni(II), Pb(II) and Cu(II) ions in the aqua phase by flame atomic absorption spectrometry. For this purpose, magnetic divinylbenzene/methacrylamide (DVB/MA/Fe3O4) and divinylbenzene/methacrylamide/graphene oxide (DVB/MA/GO/Fe3O4) were synthesised in the laboratory for use in solid-phase extraction (SPE) procedure. Analytical parameters were investigated, such as pH, eluent type and eluent volume, sample volume, matrix effects of foreign ions to proposed SPE, etc. The accuracy of the method was analysed with reference material and analyte addition to real samples. The developed method was applied to several matrices, such as water, standard reference material (BCR-146 R) and pharmaceutical samples. The detection limits of the proposed method were calculated as 9.8, 27.6, 13.6 and 7.6 µg L−1 for DVB/MA/Fe3O4 adsorbent and 2.1, 9.3, 2.3 and 11.2 µg L−1 for DVB/MA/GO/Fe3O4 adsorbent in Cd(II), Ni(II), Pb(II) and Cu(II) ions, respectively.