Polypeptide-based vesicles: formation, properties and application for drug delivery

It is well known that amphiphilic block copolymers can self-assemble in selective solvents to adopt various morphologies, such as micelles, vesicles, and cylinders. Polypeptide-containing amphiphilic block copolymers have received a great deal of attention due to their unique physicochemical and biological features. They can form vesicular structures, spontaneously mimicking the self-assemblies of virus capsids. This article focuses on recent advances involving polypeptide-based vesicles, including their formation and properties, which are significantly different from those of conventional coil-coil copolymers. The preparation of vesicles with a tunable size is also described. Unlike other polymers, polypeptides can adopt different conformations and undergo conformation transitions under specific conditions. The stimuli-responses of the vesicles based on conformation transitions will be highlighted. Polypeptides are ideal materials for gene and drug delivery because they are highly biocompatible, biodegradable, and exhibiting precise secondary conformations and inherent functionality. Polypeptide-based vesicles have shown much promise with regard to anti-cancer drug delivery.