Solid phase extraction of chromium and copper using with modified magnetic nanoparticles

In this study, magnetic Fe3O4 sorbent modified by Coomassie Brilliant Blue (CBB@Fe3O4) was synthesized and characterized. It was intended to preconcentration of Cr(III) and Cu(II) ions from water based samples using by mentioned sorbent and to determination by flame atomic absorption spectrometer (FAAS). Synthesized CBB@Fe3O4 sorbent was characterized using with FT-IR spectrometer and SEM monitoring. pH, amount of sorbent and sorption time parameters which are effective on sorption, additionally elution time, volume and concentration of eluent parameters which are effective on elution were optimized using central composite design (CCD) optimization procedure. pH 5.4, 0.0500 g sorbent amount and 30 s sorption time were calculated as optimum sorption conditions. In case of elution, 62 s elution time, 4.3 mL eluent volume and 1.1 mol/L HNO3 eluent concentration were obtained as optimum. The sampling frequency was obtained as 40 for improved method. Foreign ions interference experiments were carried out, the tolerance limit was determined as 5000 fold for Na+, Ca2+, K+, Mg2+, SO42- ions and 1000 fold for PO43- ion higher than analyte concentration. The limits of detection (LODs) of the improved method were calculated as 4.00 and 9.00 µg/L for Cr(III) and Cu(II) respectively. The limit of quantifications (LOQs) were also determined as 13.00 and 29.00 µg/L for Cr(III) and Cu(II) respectively. The validation of the method was made using by TMDA 53.3 (Ontarion lake water) certified reference material. The recovery percentages were found as 102.28 and 99.35 % for Cr(III) and Cu(II) respectively. Additionally, the applications of the method on water based samples were achieved and the recovery percentages were obtained between 80.2-102.7 % and 83.2-102.2 % for Cr(III) and Cu(II) respectively. As a result, synthesized and characterized CBB@Fe3O4 sorbent can be utilize to preconcentration of Cr(III) and Cu(II) from water based samples. The improved method can be successfully used to accurate, precise and sensitive determination of Cr(III) and Cu(II) ions.