Carbohydrate-functionalized catanionic surfactant vesicles: preparation and lectin-binding studies

In this paper we describe the modification of anionic surfactant vesicles with surfactant-based glycoconjugates of glucose, lactose, maltose and maltotriose. Catanionic vesicles were prepared by mixing cetyltrimethylammonium tosylate and sodium dodecylbenzenesulfonate to obtain thermodynamically stable, spontaneously formed vesicles. Carbohydrate moieties were linked to a hydrocarbon chain via an N-glycosyl linkage to produce an amphiphilic glycoconjugate that undergoes hydrophobic insertion into the outer bilayer leaflet of the surfactant vesicle. Once inserted, the bioavailability of the surface-adsorbed carbohydrates was determined using agglutination of the modified vesicles through selective binding of the lectins concanavalin A and peanut agglutinin. In these studies, glycoconjugates were present in the vesicle bilayer at a carbohydrate-to-surfactant ratio of approximately 1 : 100. At this coverage, vesicle formation is uninhibited, the carbohydrate groups are displayed on the vesicle outer surface and bind selectively to lectins in solution. The preparation of stable, carbohydrate-functionalized, anionic surfactant vesicles may prove useful in the targeted delivery of molecular payloads such as dyes or drugs to cells with high selectivity for a wide range of biotechnological applications.