An organic-inorganic hybrid polymer composed of a Dawson trivanadium-substituted heteropolytungstate ((Bu 4 N) 5 [H 4 P 2 W 15 V 3 O 62 ]) cluster and PS chain are originally designed and first synthesized via in situ ATRP. Further characterization includes NMR spectroscopy, FT-IR spectroscopy, and GPC which proved the purity of the material. By means of a cation exchange process, a hybrid polymer (Bu 4 N) þ -POM-PS was tuned into a novel giant amphiphile H þ -POM-PS. Immediately, individual molecules self-assembled into kinetically favored hybrid vesicles in DMF. Our work provides a controllable and rational way to fabricate stable and well-defined POM-polymer hybrid polymers that can be optimized for potential applications.

We report the construction of dumbbell-shaped hybrid molecules for programming their hierarchical supramolecular nanostructures through a synergetic self-assembly. Our first dumbbell-shaped hybrid molecule is a POM-organic-POSS cocluster produced by covalently coupling a POM cluster and a POSS cluster together through an organic tether. Structural analyses demonstrated a highly ordered lamellar morphology with a 4.9 nm periodicity, indicating a strong thermodynamic force driving a nanoscale phase separation of the POM and POSS blocks. The POM clusters were arranged in an orderly fashion within the POM-containing layer with a 1.38 nm periodicity because of fixed shape and size of the cluster. This investigation provides in-depth understanding of how to construct hierarchical supramolecular nanostructures at a nanoscale less than 5 nm by manipulating and controlling the topological shape of hybrid molecules.

Organic polymers have been found widespread commercial applications due to their easy processing and attractive mechanical properties. Concurrently, inorganic polyoxometalates (POMs), a class of metal–oxygen anionic and nanosized clusters of early transition metals, have a wide range of attractive functions and are used in industrial catalysis. In this communication, we report a new approach to creating the first linear poly(polyoxometalate)s that combine the advantages of polymers and POM clusters. In the experiment, a POM-containing norbornene monomer was first synthesized by linking a Wells-Dawson-type POM with a norbornene derivative. The monomer was polymerized in the presence of a Grubbs catalyst under mild conditions with yields nearly 100% in a living and controllable manner. The resulting poly(polyoxometalate)s have controllable molecular weights and a well-defined hybrid structure of an organic polynorbornene backbone with large pendant groups of the nanosized POM clusters. Thus, they form good films and have a good catalytic performance. Our findings not only pave the way for incorporating the POM clusters into polymers with well-defined structures and high molecular weights, but also offer a competitive strategy for developing more novel catalytic systems by introducing the poly(polyoxometalate)s.

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Amphotericin B (AmB)/poly(lactic acid)-b-poly(ethylene glycol) (PLA-b-PEG) nanoparticles coated with polysorbate 80 (Tween-80) were prepared by nanoprecipitation for transport across the blood-brain barrier (BBB). The effects of Tween-80 on the size and distribution, entrapment efficiency and release behavior of AmB/PLA-b-PEG nanoparticles were investigated. Furthermore, the brain targeting and curative effect of coated nanoparticles were also investigated. The entrapment efficiency was significantly enhanced when nanoparticles were coated with Tween-80. The prepared nanoparticles were spherical with homogeneous distribution. Drug concentration in mice brain was greatly enhanced, which indicated that the coated nanoparticles could get across the BBB. Meanwhile, the AmB/PLA-b-PEG nanoparticles are able to reduce the toxicity of AmB to liver, kidney and blood system with improved therapeutic effect.

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We report our findings on the macromolecule-to-amphiphile conversion process of a polyoxometalate-polymer hybrid and the assembled hybrid vesicles formed by aggregation of the hybrid amphiphile. The polyoxometalate-polymer hybrid is composed of a polyoxometalate (POM) cluster, which is covered by five tetrabutylammonium (Bu(4)N(+)) countercations, and a polystyrene (PS) chain. Through a cation-exchange process the Bu(4)N(+) countercations can be replaced by protons to form a hybrid amphiphile composed of a hydrophilic, protonated POM cluster and a hydrophobic PS chain. By implementing a directed one-dimensional diffusion and analyzing the diffusion data, we confirmed that the diffusion of solvated protons rather than macromolecules or aggregates is the key factor controlling the conversion process. Once the giant hybrid amphiphiles were formed, they immediately assembled into kinetically favored vesicular aggregates. During subsequent annealing these vesicular aggregates were transformed into thermodynamically stable vesicular aggregates with a perfect vesicle structure. The success in the preparation of the POM-containing hybrid vesicles provides us with an opportunity of preparing POM-functionalized vesicles.