Graphene Oxide Supported on Amberlite Resin for the Analytical Method Development for Enhanced Column Preconcentration/Sensitive Flame Atomic Absorption Spectrometric Determination of Toxic Metal Ions in Environmental Samples

Graphene oxide (GO)-layered nanosheets with a two-dimensional carbon lattice is linked to styrenic carbon of porous XAD polymeric resin via an azo spacer arm without utilizing any oxygen-containing functionality for the first time. The adopted synthesis approach makes all of the epoxy, hydroxyl, carbonyl, and carboxyl groups on the axial and basal planes of the GO sheet available for coordination with metal ions, and the introduction of hydrophilic character as result the highest preconcentration factor for Pb (500) was observed among the GO composites used as a solid-phase extractant in column operation. The developed analytical methodology using XAD-GO for the preconcentration of Pb, Cd, and Zn ions permits the use of an economically viable less sensitive atomic absorption spectrometry for their trace determination in water samples because of the enhanced quantification limit. The application of polymer-immobilized GO in a column sorts out the problem of escape of toxic GO into the environment, and under optimized solid-phase extraction conditions, the quantitative desorption of metal ion involves only 5.0 mL of 2 M HCl instead of any carcinogenic organic solvents. These two components make this method a green one. The developed method was validated by analysis of standard reference materials and recovery of the spiked analyte from real water samples.