Nanoparticulate delivery systems based on amphiphilic cyclodextrins

Cyclodextrins have been widely applied to the pharmaceutical field due to their ability to include hydrophobic molecules in their cavity and to mask certain physicochemical characteristics of the included molecule such as poor water solubility, stability problems, unwanted side effects, taste, odor, and incompatibility of drugs and excipients. As a result of the increasing interest in and successful licensing and commercialization of nanoparticulate pharmaceutical products, cyclodextrins have also been incorporated into nanoparticulate drug delivery systems for several purposes. This can be achieved by two approaches; either by complexation of active ingredient with an appropriate cyclodextrin derivative and entrapment into polymeric nanoparticles to solve problems arising from the drug's physicochemical properties or by modification of cyclodextrins to render an amphiphilic character to these molecules which allow cyclodextrins to self-align into nanoparticles in the form of nanospheres, nanocapsules, solid lipid nanoparticles, nanosize liposomes and nanosize vesicles with or without the presence of surfactants. This review will deal with the current literature concerning the applications of cyclodextrins and derivatives as nanomaterials for drug delivery focusing on nanoparticles prepared from novel cyclodextrin derivatives namely amphiphilic cyclodextrins and their in vitro characterization, efficacy and safety.