Graphene oxide nanosheets modified with trithiocyanuric acid for extraction and enrichment of Pb (II) and Cu (II) ions in seawater

Trithiocyanuric acid (TTC) is a robust chelating ligand for extracting divalent and univalent heavy metals from water samples. In this method, graphene oxide nanosheets (GO) was modified with TTC, to produce a new nano-adsorbent (GO-TTC), for extraction and preconcentration of Pb (II) and Cu (II) ions from seawater samples. The concentrated analytes were measured by a flame atomic absorption spectrometry. The detection limits of the method for Pb (II) and Cu (II) ions were 0.32 ng/mL and 0.13 ng/mL, respectively. The relative standard deviations of analytes for six successive extractions were below 1.64%. The maximum adsorption capacity of GO-TTC for Pb (II) and Cu (II) ions was 750 mu g/g and 460 mu g/g, respectively. The recoveries of the spiked analytes in artificial and natural seawater samples were above 90%, pointing out that the method is not affected by the major coexisting ions in seawater matrices.