β-cyclodextrin (β-CD) is widely used as a component of pharmaceutical formulations, classically to improve the solubility and oral bioavailability of poorly water-soluble drugs through formation of drug/β-CD inclusion complexes. Unexpectedly, the association of the highly water-soluble drug meglumine antimoniate (MA) with β-CD turned this antimonial compound orally-active in a murine model of leishmaniasis. To get insight into the mechanisms responsible for the enhanced oral efficacy of MA, the MA/β-CD composition was characterized physicochemically, using thermogravimetry, circular dichroism, mass spectrometry (ESI-MS), osmometry and photon correlation spectroscopy. The freeze-dried MA/β-CD was found to form nanoassemblies in water, as a result of multiple non-inclusion interactions between MA and β-CD, which behave as a sustained release system of the MA drug.
cyclodextrin; antimony; meglumine antimoniate; sustained release; nanobiotechnology
