Arsonoliposomes for drug delivery

Arsenic-containing liposomes or arsonoliposomes were recently prepared and characterized using novel arsenic-containing lipids, arsonolipids. Preliminary and follow up in vitro, and in vivo studies have shown that some of the arsonoliposome types studied have interesting anticancer and antiprotozoal activity. From a mechanistic point of view their activity (especially their anticancer activity) may be linked to the reduction of arsenic to its more toxic form (from As (V) to As(III)) which may be enhanced in areas where increased concentrations of thiol-containing compounds, such as glutathione, prevail, as is the case for some types of cancer cells. The physicochemical characteristics of arsonoliposomes; mean diameter, surface charge, morphology and membrane integrity are influenced by their composition. Indeed the specific arsonolipids and/or phospholipids used for their preparation, as well as the addition of cholesterol in their membrane and the relative amounts of each lipid type have been demonstrated to influence all the above mentioned vesicle characteristics. Accordingly, the antiprotozoal and in vivo distribution and kinetics were affected by arsonoliposome composition, while this is currently under investigation for anticancer activity. To conclude, the appropriate arsonoliposome type (in terms of lipid composition) should be selected when considering arsonoliposomes as nanocarriers for the delivery of drugs.