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In recent years, the self-assembly of copolymer micelles has become an appealing frontier of supramolecular chemistry as a strategy to construct superstructures with multiple levels of complexity. The assembly of copolymer micelles is a form of higher-level self-assembly occurring at the nanoscale level where the building blocks are preassembled micelles. Compared to one-step hierarchical self-assembly, this assembly strategy is superior for manipulating multilevel architectures because the structures of the building blocks and higher-order hierarchies can be regulated separately in the first and higher-level assembly, respectively. However, despite the substantial advances in the self-assembly of copolymer micelles in recent years, universal laws have not been comprehensively summarized. This review article aims to provide an overview of the current progress and developing prospects of the self-assembly of copolymer micelles. In particular, the significant role of theoretical simulations in revealing the mechanism of copolymer micelle self-assembly is discussed.

Polypeptide copolymers can self-assemble into diverse aggregates. The morphology and structure of aggregates can be varied by changing molecular architectures, self-assembling conditions, and introducing secondary components such as polymers and nanoparticles. Polypeptide self-assemblies have gained significant attention because of their potential applications as delivery vehicles for therapeutic payloads and as additives in the biomimetic mineralization of inorganics. This review article provides an overview of recent advances in nanostructures and bioapplications related to polypeptide self-assemblies. We highlight recent contributions to developing strategies for the construction of polypeptide assemblies with increasing complexity and novel functionality that are suitable for bioapplications. The relationship between the structure and properties of the polypeptide aggregates is emphasized. Finally, we briefly outline our perspectives and discuss the challenges in the field.

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As you like it: The synthesis of supramolecular hierarchical nanostructures with designed morphologies has been realized through computer-simulation-guided multicomponent assembly of polypeptide-based block copolymers and homopolymers. By adjusting the attraction between hydrophobic polypeptide rods, as well as other parameters such as the molar ratio of copolymers and the rigidity of polymers, a variety of morphologies were obtained.

We report here a discovery that amphiphilic polypeptide block copolymers and polypeptide homopolymers are able to aggregate together into super-helical structures of rods and rings, in which polypeptide chains form the core and PEG chains form the shell.

The self-assembly behavior of poly(gamma-benzyl-L-glutamate)-graft-poly(ethylene glycol) rod-coil graft copolymers in aqueous solution was investigated. With tetrahydrofuran (THF) as initial solvent, vesicles were observed for the graft copolymers with lower degree of grafting. When the degree of grafting increases, the aggregate morphology transforms from vesicles to spindle-like micelles then to spherical micelles. When N,N'-dimethylformamide (DMF) is introduced into the initial solvent, the vesicles transform to spindles. Increasing DMF volume fraction leads to a spindle to connected-spindle transition. On the basis of the experimental results, the mechanism of the morphological transition of the rod-coil graft copolymer is suggested.

Toroids and helices are fundamental geometrical structures in nature. Polymers can self‐assemble into various nanostructures, including both toroids and helices; however, nanostructures combining toroidal and helical morphologies (that is, helical toroids) are rarely observed. A binary system is reported containing polypeptide homopolymer and its block copolymer, which can hierarchically self‐assemble into uniform helical nanotoroids in solution. The formation of the helical toroids is a successive two‐step process. First, the homopolymers aggregate into fibrils and convolve into toroids, thereby resembling the toroidal condensation of deoxyribonucleic acid (DNA) chains. Second, the block copolymers self‐assemble on the homopolymer toroids and result in helical surface patterns. Additionally, the chirality of the surface helical patterns can be varied by the chirality of the polypeptide block copolymers.