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Supramolecular self‐assembly is a promising strategy for stabilizing the photo‐sensitive components in photocatalysis. However, the underlying correlation between the enhanced photostability and supramolecular structure at the molecular level has not yet been fully understood. Herein, we develop a biomimetic vesicular membrane‐based polyporphyrin photocatalyst exhibiting excellent photocatalytic stability with at least activity time of 240 h in hydrogen generation. Time‐domain ab initio modelling together with transient absorption spectroscopy, visual frontier orbitals and Gibbs free energy calculation disclose that the ordered aggregation of porphyrin units in the vesicle membrane facilitates "hot" electron relaxation and the rapid dissipation of photo‐generated charges, thereby contributing to the longevity. This work deepens the molecular‐level understanding on photostability and photocatalytic mechanism of supramolecular photocatalysts. [ABSTRACT FROM AUTHOR]

This study presents interesting self‐assembly of peapod‐like micrometer tubes from a planet‐satellite‐type supramolecular megamer, which was constructed through the specific host–guest molecular recognition between azobenzene (AZO)‐functionalized hyperbranched poly(ethyl‐3‐oxetanemethanol)‐star‐poly(ethylene oxide) (HSP‐AZO) and β‐cyclodextrin(CD)‐based hydrophilic hyperbranched polyglycerol (CD‐g‐HPG). A peapod‐like structure with micrometer‐sized tube as the pod and vesicles encapsulated inside as the peas was formed through sequential vesicle entosis, linear association, and fusion processes. Dissipative particle dynamics (DPD) simulations support the structural possibility of the supramolecular peapod formation and its mechanism. UV light irradiation could lead to the disassembly of the peapod‐like structure. This study expands the family of supramolecular polymers and opens a new avenue to develop bioinspired complex hierarchical nanoarchitectures at the microscopic level. [ABSTRACT FROM AUTHOR]

Engineering synthetic materials that mimic the complex rhythmic oscillatory behavior of living cells is a fundamental challenge in science and technology. Up to now, the reported synthetic model system still cannot compete with nature in oscillatory modes and amplitudes. Presented here is a novel alternating copolymer vesicle that exhibits drastic and multimode shape oscillations in real time, which are controlled by polymer concentrations and driven by the Belousov—Zhabotinsky oscillatory reaction, including swelling/deswelling, twisting/detwisting, stretching/shrinking, fusion/fission, and multiple division. Some of them, especially the fission oscillation, have not been observed before. In addition, the oscillation magnitude with regard to diameter is much larger than that of previously reported self‐oscillating vesicles. Such a self‐oscillating vesicle transformer would extend the complexity and capacity of membrane deformations in synthetic systems, approaching those of natural cells. [ABSTRACT FROM AUTHOR]

This communication describes polymer vesicles self-assembled from hyperbranched polymers (branched polymersomes (BPs)) as scaffolds, conceptually mimicking the natural light-harvesting system in aqueous solution. The system is constructed with hydrophobic 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) as donors encapsulated in the hydrophobic hyperbranched cores of the vesicles and the hydrophilic Rhodamine B (RB) as acceptors incorporated on the surface of the vesicles through the cyclodextrin (CD)/RB host-guest interactions, through which the donors and acceptors are spatially separated to effectively avoid the self-quenching between donors. This vesicular light harvesting system has presented good energy transfer efficiency of about 80% in water, and can be used as the ink to write multiclolor letters. In addition, due to the giant dimension of BPs, the real-time fluorescent images of the vesicles under an optical microscope can be observed to prove the light-harvesting process. It is supposed that such a vesicular light-harvesting antenna can be used to construct artificial photosynthesis systems in the future. [ABSTRACT FROM AUTHOR]

A facile and novel method for the synthesis of monodisperse hyper-crosslinking polymer nanoparticles (HPNs) is reported in the combination of vesicle bilayer templating and hyper-crosslinking technology. Monodisperse polymer nanoparticles (PNs) around 61 nm are first obtained through the confined reaction of vinylbenzyl chloride and divinylbenzene in the bilayers of the vesicles, and then the PNs are turned into HPNs through the Friedel-Crafts-type hyper-crosslinking reaction. The finally obtained HPNs demonstrate small and uniform size, high Brunauere-Emmette-Teller surface area up to ≈1300 m2 g−1, a very high micropore area above 1000 m2 g−1 and a micropore volume of 0.55 cm3 g−1. In addition, they also show the carbon dioxide adsorption capacity of 2.87 mmol g−1 (273 K, 1 bar), which is among the best CO2 adsorption property for 'Davankov Resins.' [ABSTRACT FROM AUTHOR]

Hyperbranched multiarm copolymers (HMCs) have been shown to hold great potential as precursors in self-assembly, and many impressive supramolecular structures have been prepared through the self-assembly of HMCs in solution. However, theoretical studies on the corresponding self-assembly mechanism have been greatly lagging behind. Herein, we report the self-assembly of normal or reverse vesicles from amphiphilic HMCs by dissipative particle dynamics (DPD) simulation. The simulation disclosed both the self-assembly mechanisms and dynamics of vesicles. It indicates that the self-assembly of HMCs involves several steps, from randomly distributed unimolecular micelles to small spherical micelles, to membrane-like micelles, to finally small vesicles. The membranes are formed through the direct aggregation and lateral fusion of small micelles, and the bending and closing of the membranes give rise to small vesicles. Finally, large and steady vesicles are formed through the fusion of small vesicles. In addition, the bilayer or monolayer molecular packing modes as well as the mircrophase separation behaviors of HMCs in normal or reverse vesicles have also been studied. These simulation results explore details that cannot be observed in the experiments to a certain degree, and have extended the understanding of the vesicular self-assembly process of HMCs. [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]

Front Cover: A novel non‐emulsion polymerization method to synthesize uniform and small‐sized “Davankov Resins” around 60 nm through the combined technology of bilayertemplating polymerization inside the hyperbranched polymer vesicles and hyper‐crosslinking is reported. The obtained hyper‐crosslinked polymer nanoparticles possess a high surface area, a very high micropore area, and excellent carbon dioxide adsorption property. This is reported by Caiyun Cai, Zhilin Hou, Tong Huang, Ke Li, Yannan Liu, Ning Fu, Sheng Han, and Yongfeng Zhou* in the article number 1700001. [ABSTRACT FROM AUTHOR]

Highlights • Simple and efficient polymer based aqueous detection system for toxic Hg2+. • Turn-on response visible to naked eye. • Real-time detection of Hg2+ in raw water samples. • Excellent quantifying ability in terms of percentage recovery. Abstract In recent years, there has been an ever-increasing demand to develop highly sensitive and selective colorimetric detection systems to tackle the growing threat of potentially toxic mercuric ions (Hg2+) exposure at the global level. However, most of the reported chemosensors for Hg2+ detection worked only in organic or in mixed solutions (organic/aqueous). The properties of the reported aqueous chemosensors for Hg2+ are not satisfactory. Herein, we take the advantage and present the first vesicular chemical sensor for the aqueous detection of Hg2+ with a high efficiency and selectivity. The vesicles were obtained through the aqueous self-assembly of the newly synthesized amphiphilic alternating copolymer poly(2, 3-dihydroxybutylene-alt-2,3-dihydroxybutylenedithioether) [P(DHB-a-DHBDT)] grafted with 2-(5-bromopyridine-2-yl)-3′,6′-bis(diethylamino)spiro[isoindoline-1,9′-xanthene]-3-thione (PST) probes. After the addition of Hg2+, the colorless aqueous solution of the vesicles changed into pink color accompanied by the significant enhancement of photophysical (emission and absorption) intensities at 580 nm and 559 nm, respectively. This color transition from colorless to pink allows the "bare-eye" detection of Hg2+ ions in the aqueous medium. The vesicular sensor also shows high selectivity for Hg2+ detection among miscellaneous metal cations. The detection limit (LOD) is about 53.0 nM, which is approximately one or two order of magnitude higher than those of the reported aqueous Hg2+ chemosensors. The mechanism study indicates the significant enhancement of emission and absorption intensities in response to Hg2+ should be attributed to the spirolactam ring opening via photoinduced electron transfer (PET) of xanthene moiety in the PST probes. Most importantly, the newly developed polymeric vesicle sensors shows great potential for the detection and quantification of Hg2+ with excellent selectivity in real water samples with the percentage recovery of 102–98%. [ABSTRACT FROM AUTHOR]

Abstract: A series of palmitoyl chloride-grafted hyperbranched polyglycerols were synthesized through cationic ring-opening polymerization and end-group modification. The obtained grafted copolymer of HPG-C16 possesses a hydrophilic hyperbranched polyether core and many hydrophobic alkyl arms, which shows interesting self-assembly behavior in THF and water. The results indicate that the copolymers with a relatively high alkyl grafting ratio can form unimolecular micelles in THF and will further assemble into giant vesicles around 1–10μm in THF/water mixed solvents. However, the HPG-C16 with a low alkyl grafting ratio of 15.6% can directly assemble into vesicles in THF and form micelles in water. [Copyright &y& Elsevier]