Cyclodextrin is a cyclic polymer of glycose, safe and easilly biodegradable. Cyclodextrin has well known dimensions (cavity diameter = 15.4 Å). Its spatial configuration ressembles that of a cylinder with one wide and one small opening.

Cyclodextrin is amphiphilic: the internal cavity is very hydrophobic since all hydroxyl groups are on the highly polar external surface. As a result, cyclodextrin encapsulates best apolar actives although it is very water soluble.

As sugar molecules, cyclodextrins have moisturizing properties and are completely safe and biodegradable.