ABSTRACT
Rapid growth in nanotechnology in recent years and its numerous applications in industries and agriculture have caused widespread emission of nanomaterials and their trace residues into the environment. The methods for analysis of nanomaterials in environmental samples are scant. However several techniques are known for their separation and characterization in food and agricultural samples that are mostly heterogeneous consisting mixtures of a variety of nanoparticles. The samples therefore require separations prior to their characterizations. Several techniques are known for the separation of nanomaterials. They primarily include the capillary electrophoresis (CE) and chromatographic methods. Also, flow field fractionation (FFF) techniques are often used for separations. The chromatographic methods include high-performance liquid chromatography (HPLC), ultra-performance liquid chromatography, size exclusion chromatography (SEC), and weak/strong cation or anion exchange chromatography. FFF is another effective method for separation of many types of nanomaterials. Two types of FFF techniques are mostly used: sedimentation and asymmetric flow.
