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Vesicle-vesicle aggregation to mimic cell-cell aggregation has attracted much attention. Here, hyperbranched polymer vesicles (branched-polymersomes, BPs) with a cell-like size were selected as model membranes, and the vesicle aggregation process, triggered by click chemistry of the copper-catalysed azide-alkyne cycloaddition reaction, was systematically studied. For this purpose, azide and alkynyl groups were loaded on the membranes of BPs through the co-assembly method to obtain N(3)-BPs and Alk-BPs, respectively. Subsequently, macroscopic vesicle aggregates were obtained when these two kinds of functional BPs were mixed together with the ratio of azide to alkynyl groups of about 1:1. Both the vesicle fusion events and lateral phase separation on the vesicle membrane occurred during such a vesicle aggregation process, and the fusion rate and phase-separation degree could be controlled by adjusting the clickable group content. The vesicle aggregation process with N(3) -micelles as desmosome mimics to connect with Alk-BPs through click-chemistry reaction was also studied, and large-scale vesicle aggregates without vesicle fusion were obtained in this process. The present work has extended the controllable cytomimetic vesicle aggregation process with the use of covalent bonds, instead of noncovalent bonds, as the driving force., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Hierarchical self‐assembly of synthetic polymers in solution represents one of the sophisticated strategies to replicate the natural superstructures which lay the basis for their superb functions. However, it is still quite challenging to increase the degree of complexity of the as‐prepared assemblies, especially in a large scale. Liquid–liquid phase separation (LLPS) widely exists in cells and is assumed to be responsible for the formation of many cellular organelles without membranes. Herein, through integrating LLPS with the polymerization‐induced self‐assembly (PISA), a coacervate‐assisted PISA (CAPISA) methodology to realize the one‐pot and scalable preparation of hierarchical bishell capsules (BCs) from nanosheets with ultrathin lamellae phase (sub‐5 nm), microflakes, unishell capsules to final BCs in a bottom‐up sequence is presented. Both the self‐assembled structure and the dynamic formation process of BCs have been disclosed. Since CAPISA has combined the advantages of coacervates, click chemistry, interfacial reaction and PISA, it is believed that it will become a promising option to fabricate biomimetic polymer materials with higher structural complexity and more sophisticated functions. [ABSTRACT FROM AUTHOR]

The cytoskeleton is one of the most important cellular components. Up to now, most of the reported artificial cytoskeletons are based on a gel‐in‐vesicle strategy. Herein, we report a membrane‐bound inward‐growth pathway to prepare cytoskeleton‐like and radially aligned nanofibers grown from capsule membranes to get membrane‐bound artificial cytoskeletons (MACs). The mechanism therein is disclosed through the direct observation of the intermediates in both dried and liquid states. Furthermore, the as‐prepared MACs show a selective disassembly behavior in the presence of reductants: both capsule membranes and MACs can be disassembled or only MACs can be disassembled through the selective introduction of dynamic disulfide bonds (DS) into them and by the switch of ultraviolet (UV) irradiation. The present work provides a new hierarchical self‐assembly way to construct artificial cytoskeletons with controlled compositions and orientations. [ABSTRACT FROM AUTHOR]

Marine mussels have the ability to cling to various surfaces at wet or underwater conditions, which inspires the research of catechol‐functionalized polymers (CFPs) to develop high‐performance adhesive materials. However, these polymeric adhesives generally face the problems of complex synthetic route, and it is still high challenging to prepare CFPs with excellent adhesive performance both at dry and underwater conditions. Herein, a mussel‐inspired alternating copolymer, poly(dopamine‐alt‐2,2‐bis(4‐glycidyloxyphenyl)propane) (P(DA‐a‐BGOP)), is synthesized in one step by using commercially available monomers through epoxy‐amino click chemistry. The incorporation of polar groups and rigid bisphenol A structures into the polymer backbone enhances the cohesion energy of polymer matrix. The alternating polymer structure endows the polymers with high catechol content and controlled polymer sequence. As a result, P(DA‐a‐BGOP) exhibits a strong bonding strength as high as 16.39 ± 2.13 MPa on stainless steel substrates after a hot pressing procedure and displays a bonding strength of 1.05 ± 0.05 MPa on glass substrates at an under‐seawater condition, which surpasses most commercial adhesives. [ABSTRACT FROM AUTHOR]

Abstract: Hierarchical solution self‐assembly has become an important biomimetic method to prepare highly complex and multifunctional supramolecular structures. However, despite great progress, it is still highly challenging to prepare hierarchical self‐assemblies on a large scale because the self‐assembly processes are generally performed at high dilution. Now, an emulsion‐assisted polymerization‐induced self‐assembly (EAPISA) method with the advantages of in situ self‐assembly, scalable preparation, and facile functionalization was used to prepare hierarchical multiscale sea urchin‐like aggregates (SUAs). The obtained SUAs from amphiphilic alternating copolymers have a micrometer‐sized rattan ball‐like capsule (RBC) acting as the hollow core body and radiating nanotubes tens of micrometers in length as the hollow spines. They can capture model proteins effectively at an ultra‐low concentration (ca. 10 n m) after functionalization with amino groups through click copolymerization. [ABSTRACT FROM AUTHOR]

Well-defined ultrathin nanotubes (30 nm in diameter and of micrometer-scale length) were generated through the self-assembly of a novel alternative copolymer synthesized using an epoxy-thiol click-chemistry reaction. The self-assembly mechanism was investigated both by experiments and using dissipative particle dynamics (DPD) simulations. The obtained nanotubes can be readily functionalized with carboxy groups, amino groups, peptides, or other groups by simple modular click copolymerization. [ABSTRACT FROM AUTHOR]

Vesicle-vesicle aggregation to mimic cell-cell aggregation has attracted much attention. Here, hyperbranched polymer vesicles (branched-polymersomes, BPs) with a cell-like size were selected as model membranes, and the vesicle aggregation process, triggered by click chemistry of the copper-catalysed azide-alkyne cycloaddition reaction, was systematically studied. For this purpose, azide and alkynyl groups were loaded on the membranes of BPs through the co-assembly method to obtain N3-BPs and Alk-BPs, respectively. Subsequently, macroscopic vesicle aggregates were obtained when these two kinds of functional BPs were mixed together with the ratio of azide to alkynyl groups of about 1:1. Both the vesicle fusion events and lateral phase separation on the vesicle membrane occurred during such a vesicle aggregation process, and the fusion rate and phase-separation degree could be controlled by adjusting the clickable group content. The vesicle aggregation process with N3-micelles as desmosome mimics to connect with Alk-BPs through click-chemistry reaction was also studied, and large-scale vesicle aggregates without vesicle fusion were obtained in this process. The present work has extended the controllable cytomimetic vesicle aggregation process with the use of covalent bonds, instead of noncovalent bonds, as the driving force. [ABSTRACT FROM AUTHOR]