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[Display omitted] • A bipyridine containing homopolymer is synthesized to prepare various nanostructures via different self-assembly pathways. • Bowl-shaped nanoparticles with controlled size and openings are obtained by controlling the initial concentration. • A fusion induced assembly behavior is found to form nanosheets using nanowires as building block. The control of the morphology and nanostructure of soft nanomaterials self-assembled from amphiphilic polymers has attracted significant attention. In this study, various nanostructures including bowl-shaped nanoparticles with controlled openings, round Yuanbao-shaped assemblies, nanowires and butterfly shaped twin nanosheets are formed by manipulating the self-assembly pathway of an amphiphilic homopolymer. The amphiphilic (poly(N -(2,2′-bipyridyl-4-acrylamide), PBPyAA) with bipyridine pendants is designed and synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization, which can self-assemble into bowl-shaped nanoparticles with controlled openings by solvent switch method at different initial concentrations. In addition, core–shell nanostructures are obtained taking advantage of the coordination between bipyridine and Fe2+. Upon annealing in ethanol, butterfly shaped twin nanosheets with thickness of about 10 nm are formed by controlling the cooling rate, while round Yuanbao-shaped assemblies are formed by naturally cooling. Revealing into the formation mechanism of the butterfly shaped twin nanosheets, a fusion induced assembly process of nanowires is observed. Overall, various nanostructures are obtained by manipulating the self-assembly pathways of a bipyridine containing amphiphilic homopolymer. [ABSTRACT FROM AUTHOR]

• Amphiphilic double brush homopolymers open new era of self-assemblies in water. • Uniform micelles, unimer micelles, and rod micelles can be produced as desired. • The micelle morphology is controlled by the pendant design and chain length. • More hydrophobic homopolymers induce morphology transition at shorter chain length. • Discrete micelles are simultaneously formed via the self-sorting of the homopolymers. In this paper, we examined self-assembly of amphiphilic homopolymers bearing the double brush side chains of a hydrophilic PEG and various hydrophobic units including butyl, octyl, dodecyl, octadecyl, and oleyl groups in water. Analyzed by size exclusion chromatography coupled with multiangle laser light scattering, those homopolymers formed uniform micelles, unimer micelles, and large aggregates like rod micelles in water; the morphology depended on the hydrophobic side chains and changed at a certain threshold degree of polymerization (DP th). The homopolymer comprising butyl groups folded into compact micelles via intramolecular association in water, independent of molecular weight. In contrast, the homopolymer carrying octyl groups formed either uniform micelles via multichain association (DP th). The homopolymers carrying dodecyl, octadecyl, and oleyl groups exclusively undergo multichain association in water but form either uniform micelles (DP th). Uniquely, those DP th values decreased with increasing the hydrophobicity of the pendants; more hydrophobic homopolymers tend to form large aggregates at shorter polymer chains. Additionally, those homopolymers with broad molecular weight distribution induced chain length-dependent self-sorting to simultaneously produce uniform micelles and large aggregates in water. [ABSTRACT FROM AUTHOR]

• A metal-chelating polymer was synthesized with deferoxamine, polyethylene glycol, and fluorescein pendant groups and a biotin end-group. • The metal-chelating polymer was labeled with Zr, and then the polymer was conjugated to streptavidin-coated polymeric microspheres. • The Zr chelating polymers conjugated to the polymeric microspheres was imaged using Imaging Mass Cytometry™ and epifluorescence microscopy. Mass cytometry (MC) uses antibodies (Abs) labeled with heavy metal isotopes to monitor biomarker expression on individual cells. Metal-chelating polymers (MCPs) conjugated to the Abs increase the number of metal ions carried per Ab, and this increases the signal generated per Ab. Although the MC detector can detect 134 metal isotopes with unique weight simultaneously, in the current literature a maximum of 43 isotopes have been analyzed simultaneously. Currently available MCPs for MC are well-suited for use with lanthanides and bismuth, but are incompatible with other metals of interest. Here we examine a new MCP with deferoxamine pendant groups designed to chelate Zr ions. Zr has 4 isotopes useful for MC. To overcome the limited water solubility of deferoxamine groups, we introduced pendant polyethylene glycol chains. The polymer also included fluorescein pendant groups, along with a biotin terminal end-group. Once loaded with Zr, the polymers were incubated with streptavidin-coated polystyrene microbead and analyzed using epifluorescence microscopy and imaging MC. [ABSTRACT FROM AUTHOR]