Determination of iron and copper in edible oils by flame atomic absorption spectrometry after liquid-liquid extraction

Abstract

In the present work, a novel and rapid extraction method for Fe(III) and Cu(II) from liquid edible oils is described. N,N'-Bis(4-methoxysalicylidene)-1,2-diamino ethane (MSE) was utilized for the extraction of metal ions and the determination was achieved by flame atomic absorption spectrometry (FAAS). In order to optimize the extraction conditions, a central composite design (CCD) technique was employed. The optimum conditions, the ratio of MSE solution volume to oil mass, stirring time and temperature, were determined as 1.2 and 1.1 mL g(-1); 24.0 and 31.8 min and 25.3 and 33.2 A degrees C for Fe(III) and Cu(II) extraction, respectively. The feasibility of the improved method was tested with oil-based metal standards affording 98.6 % recovery for both metals and 67.3 ng g(-1) for Fe(III) and 15.3 ng g(-1) for Cu(II) as limit of detection (LOD).