Cyclodextrins (CDs) are cyclic oligosaccharides produced by enzymatic degradation of starch. The most common CDs are the main natural ones, α, β and γ, which are constituted of 6, 7 and 8 glucopyranose units, respectively. The CD structure forms a torus or doughnut ring and the molecule actually exists as a truncated cone. The outer side of the toroid is hydrophilic in nature due to the hydroxyl groups of the glucopyranose units while the internal cavity is relatively apolar. Thus, CDs have a high potential to entrap entirely or partially a wide variety of compounds in a process known as complexation. This gives them new physico-chemical properties and characteristics. The main applications of CDs in drug formulation rely on CD complexation and include the protection of easily oxidizable molecules or the improvement of aqueous solubility. The use of CDs in analytical chemistry is based on his host-guest recognition property, known as supramolecular complex formation. Currently, CDs are successfully used in molecular recognition-based methods like chromatographic separations, spectroscopic and electroanalyses. Quiral analytical separations are a CD area of special relevance. In this work, attention is paid to more recent references, especially to selected reviews.
Part of the book: Cyclodextrin