N Akbari - Department of Chemistry, Damghan University, Damghan, ۴۱۱۶۷-۳۶۷۱۹, Iran.

We are introducing graphene oxide modified with amine groups as a new solid phase for extraction of heavymetal ions including cadmium(II), copper(II), nickel(II), zinc(II), and lead(II). Effects of pH value, flow rates, type,concentration, and volume of the eluent, breakthrough volume, and the effect of potentially interfering ions were studied.Under optimized conditions, the extraction efficiency is >97 %, the limit of detections are 0.03, 0.05, 0.2, 0.1, and 1 μgL−1 for the ions of cadmium, copper, nickel, zinc, and lead, respectively, and the adsorption capacities for these ionsare178, 142, 110, 125, and 210 mg g−1. The aminofunctionalized graphene oxide was characterized by thermogravimetricanalysis, transmission electron microscopy, scanning electron microscopy, and Fourier transform infrared spectrometry.The proposed method was successfully applied in the analysis of environmental water and food samples. Good spikedrecoveries over the range of 95.8–100.0% were obtained. This work not only proposes a useful method for samplepreconcentration but also reveals the great potential of modified graphene as an excellent sorbent material in analyticalprocesses.

Amine-functionalized graphene oxide ; Solid phase extraction ; Preconcentration ; Heavy metals