A non-destructive analytical protocol for simultaneous separation and preconcentration of Cd(II) and Cu(II) from edible oils prior to FAAS determination.

In this study, a vortex-assisted dispersive magnetic solid-phase extraction method was developed for Cd(II) and Cu(II) in edible oils using previously synthesized/characterized Sudan III modified Fe3O4 for the first time. Determination of analytes were achieved using FAAS. Analytical parameters that were effective on sorption and elution, including vortexing time, mass of sorbent, volume of sample, concentration and volume of eluent were optimized using central composite design. The simultaneous operating conditions were as follow: vortexing time 40 s, mass of sorbent 0.25 g, sample volume 20 mL for sorption and vortexing time 60 s, concentration of HNO3 0.25 mol L-1, volume of HNO3 6 mL for elution. Limits of detection/quantification were 15.4/51.5 μg kg-1 for Cd(II) and 11.2/37.2 μg kg-1 for Cu(II). RSD values were ≤ 2.6% for both analytes and PFs were calculated as 4.46 and 3.43 for Cd(II) and Cu(II), respectively. The method was successfully applied on various edible oils.