Magnetic graphene oxide as a valuable material for the speciation of trace elements

Magnetic solid phase extraction (MSPE) has been explored for the application in preconcentration processes to achieve highly sensible analytical methods. Attending to the different magnetic adsorbent materials used in this field, functionalized magnetic graphene oxide (MGO) has proven to be effective for selective analysis and speciation of metals, metalloids, and derivatives in combination with several analytical techniques. Despite the increasing number of articles on speciation of trace elements using functionalized MGO as solid phase adsorbent, there are no dedicated reviews that cover the application of this novel nanomaterial, being this work pioneer in this area. This article provides a comprehensive review of the relevant literature related to the speciation of Al, Cr, As, Se, Ag, Cd, Hg, Tl and Pb, with special focus on species determined, toxicity, MGO functionalization, analytical performance, and applications, mainly to environmental and food samples. Finally, future challenges and trends related to this topic are shown. [Display omitted] •Updated review of MSPE for trace elements speciation using MGO as sorbent.•MGO is especially fit for purpose of speciation analysis.•The speciation mechanism based on the selective adsorption is the most extended.•Trends and challenges include the use of ecologic MGO synthesis routes.