Responsive Supramolecular Vesicles Based on Host-Guest Recognition for Biomedical Applications

Abstract

Fabrication of responsive materials is an important research area, which is intimately associated with advanced applications such as smart delivery systems, stimulus-responsive actuators, and soft robots. To achieve responsive materials, the utilization of noncovalent forces to integrate organic building units is a favorable approach. Such supramolecular self-assembly is sensitive to specific stimuli such as light, pH, temperature, and redox agents. Among noncovalent forces, host-guest interaction occurring between macrocyclic hosts and guest molecules can combine two or more species into an amphiphile system that gives rise to diverse micro-/nanostructures after the self-assembly. Compared to normal amphiphiles, host-guest amphiphiles show high sensitivity to external stimuli, demonstrating advantages in the fabrication of smart materials. In this chapter, we discuss the preparation, characterization, and application of external stimulus-responsive vesicle systems self-assembled from integrated host-guest building blocks. By summarizing recent important developments, we introduce the preparation of vesicular structures according to the type of macrocylic hosts. Then, general principles for achieving stimulus responsiveness are discussed. Finally, we highlight some biomedical applications of responsive supramolecular vesicles prepared from host-guest amphiphiles. It is expected that this chapter would provide useful information to researchers who are interested in the areas of supramolecular chemistry, self-assembly, responsive materials, and supramolecular theranostics.