Carbon-based sorbents: carbon nanotubes.

Carbon nanotubes (CNTs), as an advanced material, have been widely used in various fields since its discovery in 1991. In recent years, as an excellent adsorption material, the pure and modified CNTs are successfully used for the purification and enrichment of food, medicine, environmental samples and so on. In this review, we focus on the detailed description of different CNTs-based extraction modes such as solid-phase extraction (SPE) (including cartridge and disk SPE, dispersive SPE, and μ-SPE) and solid-phase microextraction (SPME) (including fiber SPME, electrosorption-enhanced SPME, stir bar sorptive extraction, needle trap SPME, and hollow fiber SPME).