Macrocyclic amphiphiles.

In this critical review, we summarize recent results in the investigation of macrocyclic amphiphiles, amphiphiles based on macrocyclic frameworks. These interesting molecules have drawn a lot of attention over the past decades due to their unique superiority in self-assembly processes and other advantages. Compared with traditional linear amphiphiles, macrocyclic amphiphiles can be tailored to promote their self-assembly into various well-defined architectures by locating hydrophilic and hydrophobic chains on the respective sides. Since macrocyclic amphiphiles can be regarded as "surfactants" with host-guest recognition sites, they may be highly beneficial for applications where guest molecules must be stabilized, transported or protected in aqueous media. Considering the abundant research results on the host-guest chemistry of macrocycles, the use of macrocyclic amphiphiles in the fabrication of multidimensional and hierarchical self-assemblies may also provide interesting new topological structures. Moreover, the interactions of their self-assemblies can be mediated by molecular recognition, which may further our understanding of biological processes.