Cyclodextrins (CDs) are cyclic oligosaccharides formed a-D-glucopyranosyl units which are linked together via a series of a(1,4)-glycosidic linkages. The most common three members are called a, b and g-CDs which are formed with 6, 7 and 8 glucose unit respectively. The molecules have a truncated cone-shaped geometry with all the primary hydroxyl groups present at the narrower end and all the secondary hydroxyl groups at the wider end. All the macrocyclic molecules possess a cavity with diameter of ~9 to 12 A at the narrow end and height of 7.9 Å. Because the cavities are relatively hydrophobic, all CDs can be used to form inclusion complexes with organic compounds in polar solvents such as water.
- Different types of cylodextrins
Cyclodextrins are commonly used:
- in the pharmaceutical industries as excipients and drug delivery.
- in cosmetic, personal and toiletry for a) volatility suppression of fragrance – perfume deodorants, air fresheners, b) odour control – detergents, c) better availability of active ingredient – toothpaste.
- in the food industry (flavour protection and flavour delivery), in pharmaceuticals (excipients) and in agricultural and chemical industries.
Information courtesy of The Ling Research Group Web Page http://www.ucalgary.ca/ccling/