Self-assembly of fullerene C60-based amphiphiles in solutions

Fullerene C60 is an all-carbon cage molecule with rich physicochemical properties. It is highly symmetric and hydrophobic, which can be used as a building block for the preparation of amphiphiles that self-assemble into diverse supramolecular structures in aqueous solutions. Meanwhile, C60 is also lipophobic, which is different from the alkyl chains in traditional surfactants. By attaching alkyl chains to the C60 sphere, a new type of lipophobic-lipophilic amphiphiles can be constructed which undergo self-assembly in n-alkanes. When inorganic clusters such as polyoxometalate are linked to the C60 sphere, organic-inorganic hybrids will be obtained which can self-assemble in polar organic solvents. Pristine C60 has also been modified by polar groups such as hydroxy and carboxy, which are linked to hydrophobic moieties and form a new class of amphiphiles. In this review, the self-assembly of C60-based amphiphiles in aqueous and nonaqueous solutions will be summarized. The characteristics exhibited by C60-based amphiphiles during the self-assembly will be discussed with close comparison to traditional surfactants, and the influences of the aggregate formation on the physicochemical properties of the C60 sphere will be described. Finally, a brief summary will be given together with a promising perspective in near future.