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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]

This study reports a new category of stimuli-responsive morphological transitions, i.e., from one morphology (e.g., vesicles) to another two different ones (e.g., nanosheets and nanofibers), by investigating the light-responsive self-assembly behaviour of a “latent double-amphiphilic” linear-hyperbranched supramolecular block copolymer. [ABSTRACT FROM AUTHOR]

Amicelle-like hybrid natural-artificial light-harvesting nanosystem was prepared through protein-framed electrostatic self-assembly of phycocyanin and a four-armed porphyrin star polymer. The nanosystem has a special structure of pomegranate-like unimolecular micelle aggregate with one phycocyanin acceptor in the center and multiple porphyrin donors in the shell. It can inhibit donor self-quenching effectively and display efficient transfer of excitation energy (about 80.1%) in water. Furthermore, the number of donors contributing to a single acceptor could reach as high as about 179 in this nanosystem. [ABSTRACT FROM AUTHOR]

Vesicles, including lipid vesicles, surfactant vesicles, as well as polymer vesicles, have been extensively investigated over the past fifty years. Among them, polymer vesicles have attracted more and more attention because of their low permeability, superior stability and toughness, in addition to the numerous possibilities for tailoring physical, chemical and biological properties. Polymer vesicles are generally fabricated through the self-assembly of amphiphilic polymers with a linear architecture. Recently, as representative polymers with a highly branched three-dimensional architecture, hyperbranched polymers have also exhibited great potential for preparing vesicles. The resultant hyperbranched polymer vesicles, defined as branched-polymersomes (BPs), have shown unique properties, such as giant and easily tuned vesicle sizes, facile functionalization, a special formation mechanism, and appealing solution behaviours. In this tutorial review, ten years of advances in BPs have been summarized since their first discovery in the year 2004, including the syntheses of vesicle-forming hyperbranched polymers, self-assembly methods, self-assembly mechanisms, as well as the special properties. In addition, the cytomimetic, biomedical and other initiatory applications of BPs are also included. [ABSTRACT FROM AUTHOR]

The macroscopic molecular self-assembly of an amphiphilic hyperbranched copolymer in acetone generated multiwalled tubes millimeters in diameter and centimeters in length. The thickness of the tube walls approaches 400 nanometers, and the walls have an inhomogeneous lamella structure that alternates between ordered hydrophilic domains and amorphous, partly irregular hydrophilic domains. [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: Polymeric micelles are recognized as very promising nanocarriers for small-molecule drugs, DNA, and proteins delivery. Polyphosphates are an important class of eminent biomaterials and widely used in biomedicine due to their good biocompatibility, biodegradability, and flexibility in adjusting the pendant structures. Here, some full-polyphosphate nanocarriers have been constructed successfully through self-assembly of amphiphilic hyperbranched multiarm copolymers (denoted as HPHEEP-star-PPEPs). The hydrophilic core and hydrophobic multiarm of HPHEEP-star-PPEPs are composed by hyperbranched and linear polyphosphates respectively. HPHEEP-star-PPEPs can self-assembly into nanocarriers in aqueous media with controlled size from 48 to 74nm by conveniently adjusting the length of hydrophobic arm. These nanocarriers possess excellent biocompatibility against NIH 3T3 cells and are easily internalized by vivid cells. Chlorambucil-loaded nanocarriers were investigated for proliferation inhibition of an MDA-MB-231 breast cancer cell line in vitro, and the chlorambucil dose required for 50% cellular growth inhibition was found to be 3μg/mL. [Copyright &y& Elsevier]

Abstract: A drug nanocarrier has been constructed through self-assembly of phospholipid analogous hyperbranched polymers (HPHEEP-alkyls) which contain a polar hyperbranched polyphosphate headgroup and many aliphatic tails. HPHEEP-alkyls were synthesized by self-condensing ring-opening polymerization of 2-(2-hydroxyethoxy)ethoxy-2-oxo-1,3,2-dioxaphospholane and then capped with palmitoyl chloride. Benefiting from the amphiphilic structure with the hydrophilic core and many hydrophobic tails, HPHEEP-alkyls were able to self-assemble into nanomicelles in aqueous media. Importantly, the size of the nanomicelles could be controlled conveniently from 98 to 215nm by adjusting the capped fraction of the hydroxyl groups with hydrophobic palmityls. The excellent biocompatibility of these nanomicelles was confirmed by methyl tetrazolium assay and acridine orange/ethidium bromide double staining against COS-7 cells. Confocal laser scanning microscopy and flow cytometry analysis demonstrated their good cell permeability, i.e. these nanomicelles were easily internalized by vivid cells and mainly located in the cytoplasm rather than nucleolus. Chlorambucil-loaded nanomicelles were investigated for proliferation inhibition of a MCF-7 breast cancer cell line in vitro, and the chlorambucil dose required for 50% cellular growth inhibition was found to be 5μg/mL. All of these results indicate that HPHEEP-alkyls nanomicelles can be used as safe and promising drug nanocarriers. [Copyright &y& Elsevier]

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]

Review: 182 refs. [ABSTRACT FROM AUTHOR]