Lipidic Vesicles and Amphiphilic CyDs

Cholesteryl-cyclodextrins Cholesteryl-CyDs have been designed, and are obtained by grafting a cholesterol group onto a CyD. Indeed, cholesterol is described as a phospholipid-bilayer stabilizer and the cholesterol part of cholesteryl-CyDs can enter this bilayer whereas CyD, the hydrophilic part, is located in the internal and external aqueous media between bilayers [90, 91]. 

Other Amphiphilic Cyclodextrins Other amphiphilic CyDs as well as cholesteryl-CyDs can form lipidic vesicles. These vesicles can be liposomes or vesicles delimited by the bilayer of amphiphilic molecules, sometimes incorrectly named liposomes . 

The preparation methods of these vesicles are various. In some cases, the liposomal suspension is firstly prepared and then amphiphilic CyDs are inserted inside the phospholipid-bilayer, for example by sonication [93]. Another method mixes phospholipid (+/— cholesterol) and amphiphilic CyD solutions, to form hposomes by conventional methods [92, 94]. Lastly, vesicles consisting of bilayers of purely amphiphilic CyDs as raw material can be prepared applying a technique used to prepare hposomes, i.e. hydration of lipidic film followed by sonication [99-101]. 

The introduction of amphiphilic CyDs within vesicles presents the following advantages  

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