Recent trends in the application of the newest carbonaceous materials for magnetic solid-phase extraction of environmental pollutants

• New carbon materials for magnetic solid-phase extraction (MSPE).
• Novel MSPE procedures for environmental pollutants.
• Recent applications of nanocarbons, graphene and graphitic carbon nitride.
• Properties and analytical performance of magnetic composite sorbents.
• Role of derivatization in orienting MSPE sorption and selectivity.

This paper provides a review of the latest applications of carbon-based materials for magnetic solid-phase extraction (MSPE), an advantageous sample pre-treatment increasingly adopted in analytical chemistry. In particular, this review focuses on the pre-concentration procedures developed for the determination of various classes of pollutants in environmental matrices. Beside the recent advances in the application of carbon nanotubes (CNTs), the newest carbonaceous materials have been considered, namely differently arranged nanocarbons (NCs), graphene (GN) and graphitic carbon nitride (g-C3N4). The analytical performance of the magnetic composites was critically discussed in relation to the physical–chemical properties resultant from the synthetic routes. The new sorbents generally afforded high extraction efficiency, good selectivity in complex matrices and durability for tens adsorption/desorption cycles, mainly due to high surface area, chemical stability, dispersibility in aqueous solution and, importantly, multi-type interaction. In particular, this was greatly enhanced by combining magnetic GN with other substrates or using derivatized GN, obtaining mixed-mode sorbents. The ease of preparation, durability and high enrichment factor make this new generation of MSPE carbon-based sorbents a valid alternative to the commercial solid phases.