Synthesize and modification of nano graphene oxide as solid phase adsorbent for separation and preconcentration of Iron(III) and Zinc ions from foods, soil and biological

A simple and selective method for the preconcentration of Fe(III) and Zn ions prior to flame atomic absorption spectrometric (FAAS) determinations using a column packed with nano graphene oxide (GO) as a solid-phase extractant has been presented in this manuscript. The method is based on the sorption of mentioned ions on synthesized GO with use of Methyl-2-(4-methoxy-benzoyl)-3- (4-methoxyphenyl)-3-oxopropanoylcarbamate) as chelating agent. Some effective parameters on the extraction and complex formation were selected and optimized. Under the optimized conditions (pH 9, flow rate 9 mL min−1), metal ions were retained on the column, then quantitatively eluted by 5 mL 3.0 mol L−1 HNO3 solution. The preconcentration factor was calculated as 240. The detection limits for the understudy analyte ions were found in the range of 0.22 ng mL-1 to 0.28 ng mL-1 (for Fe3+ and Zn2+, respectively). The column packed with GO was good enough for metal ions separation in matrixes containing alkali, alkaline earth, transition and heavy metal ions. This method was also used to determine the recovery rate of the studied ions in real samples.