A Brief Overview of Nanomaterials in Inorganic Selenium Speciation

Although total selenium content is still useful in many areas, knowledge of its speciation is gaining importance as its various chemical forms have different environmental effects, toxicities and biological utilization. Among several methods used for the isolation and enrichment of selenium species, solid-phase extraction and its alternative approaches are often applied due to their simplicity and high efficiency. This brief overview summarizes the progress made in using different nanostructure sorbents to separate and preconcentrate inorganic selenium species in environmental waters. Nanomaterials are finding increasing applications as they have a large specific surface area and high chemical stability. Functionalizing their surface by covalent or noncovalent interactions with other components, grafting or doping with heteroatoms can improve the separation and removal efficiency. Strategies based on combining selective chemical reactions and separation procedures are discussed.