Analytical sample preparation, preconcentration and chromatographic separation on carbon nanotubes

Carbon nanotubes (CNTs) are excellent sorbents with unique properties that have allowed them to be used for sample preparations in chemical analysis as well as chromatographic separations. They show high specific sorption capacity even for low molecular weight compounds such as CO₂ and methane, and at the same time, their nonporous structures provide faster mass transfer which allows efficient desorption of large molecules from their surface. Therefore, CNTs have been used as sorbents for small as well as macromolecules. This review highlights the applications of CNTs and CNT-based materials in some important analytical scale separations, namely stationary phase in gas, liquid and electro chromatography, sorbents for gas phase preconcentration, solid phase extraction, solid phase micro extraction and membrane separations.