Application of Nanomaterials in Solid and Liquid Microextraction

Nanomaterials (NMs) have attracted great attention in sample preparation. In particular, because of their high surface-to-volume ratios, NMs facilitate the implementation of microextraction techniques. Additional advantages derived from NMs are the possibility of increasing the selectivity through the functionalization of their surfaces, and the improvement of mechanical and thermal stability of the extraction devices. This chapter summarizes the main uses of NMs in solid and liquid microextraction techniques, and representative examples of applications are presented.

The fabrication of coatings for fiber solid-phase microextraction (SPME) is the main objective in many of the scientific research developed in the area. For this purpose, a variety of NMs have been used such as carbon-based NMs, especially carbon nanotubes (CNTs) and graphene, metallic and silica-based NMs, and more recently, metal-organic frameworks (MOFs). NMs have also been used to prepare new sorbents for other microextraction techniques such as in-tube solid-phase microextraction(ITSPME) and stir bar sorptive extraction (SBSE). The employment of magnetic nanoparticles (MNPs) has recently been introduced in microextraction, which leads to a new technique termed magnetic IT-SPME. Although the number of applications is still low, NMs are also receiving increasing attention in the main techniques of liquid phase microextraction namely, singe drop microextraction (SDME), hollow-fiber liquidphase microextraction (HF-LPME) and dispersive liquid-liquid microextraction (DLLME).

Keywords: Carbon nanotubes (CNTs), Dispersive liquid-liquid microextraction (DLLME), Fiber coatings, Fiber solid phase microextraction (fiber SPME), Graphene, Head space solid-phase microextraction (HS-SPME), Hollow-fiber liquid-liquid microextraction (HF-LPME), In-tube solid phase microextraction (IT-SPME), Liquidphase microextraction (LPME), Magnetic in-tube solid phase microextraction, Magnetic nanoparticles (MNPs), Metal organic frameworks (MOFs), Metallic nanoparticles, Multiwalled carbon nanotubes (MWCNTs), Nanomaterials (NMs), Nanoparticles (NPs), Silica nanoparticles, Single-drop microextraction (SDME), Single-walled carbon nanotubes (SWCNTs), Solid phase microextraction (SPME), Stir-bar sorptive extraction (SBSE).