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In this study, In this study, MnO 2 self-assembled on a PP separator via KMnO 4 photodecomposition, coupled with biochar to form a composite-modified separator with enhanced conductivity. It captures and converts polysulfides to Li 2 S 2 /Li 2 S, cyclically reducing Li-PS mobility. This composite separator demonstrates impressive electrochemical performance in Li-S batteries. [Display omitted] Addressing the shuttle effect is a critical challenge in realizing practical applications of lithium-sulfur batteries. One promising avenue refers to the surface modification of separators, transitioning them from closed to open structures. In the current investigation, a high ion flux separator was devised by means of MnO 2 self-assembly onto a Porous Polypropylene (PP) separator, subsequently coupling it with biochar. The separator exhibited favorable ion and electronic conductivity. Moreover, it adeptly captured and transformed polysulfides into Li 2 S 2 /Li 2 S, cyclically curbing the mobility of Polysulfide lithium (LiPSs). In addition, this augmentation in the kinetic conversion of LiPSs during the electrochemical process translated into an impressive discharge specific capacity and area capacity of 939 mAh/g and 4 mAh cm−2, respectively. Moreover, this innovative design methodology provides an alternative avenue for future separator designs within lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Controllable construction and manipulation of artificial multi-compartmental structures are crucial in understanding and imitating smart molecular elements such as biological cells and on-demand delivery systems. Here, we report a liquid crystal droplet (LCD) based three-dimensional system for controllable and reversible ingestion and release of guest aqueous droplets (GADs). Induced by interfacial thermodynamic fluctuation and internal topological defect, microscale LCDs with perpendicular anchoring condition at the interface would spontaneously ingest external components from the surroundings and transform them as radially assembled tiny GADs inside LCDs. Landau–de Gennes free-energy model is applied to describe and explain the assembly dynamics and morphologies of these tiny GADs, which presents a good agreement with experimental observations. Furthermore, the release of these ingested GADs can be actively triggered by changing the anchoring conditions at the interface of LCDs. Since those ingestion and release processes are controllable and happen very gently at room temperature and neutral pH environment without extra energy input, these microscale LCDs are very prospective to provide a unique and viable route for constructing hierarchical 3D structures with tunable components and compartments. [ABSTRACT FROM AUTHOR]

Anaplastic thyroid cancer (ATC) is an undifferentiated subtype of thyroid cancer with a markedly poor survival prognosis, estimated to occur 3–5 months after diagnosis. Akt activation is reportedly involved in tumorigenesis during ATC and represents a new therapeutic target. Based on the Akt1/bisubstrate complex structure and artificial intelligence-assisted peptide drug screening, we designed a self-assemble Akt1-targeting peptide drug exhibiting a 0.89-nm structure and potential killing ability in ATC cells. The developed self-assemble Akt1-targeting peptide drug presented IC 50 values of 18.2 μM and 12.4 μM in 8303C and 8505C cells, respectively, after 72 h of incubation. • We report the first AI (artificial intelligence) assisted intracellular Akt1 peptide inhibitor design. • The peptide drug can self-assemble into nanostructures and function without the need for an additional delivery system. • The peptide drug provides a new solution for anaplastic thyroid cancer therapy. [ABSTRACT FROM AUTHOR]

ZnCdS nanoflowers were prepared by adjusting the molar ratio of precursor in the absence of surfactant. ZCS nanorods self-assemble into the structure of a nanoflower, so that charges on the nanorods can transfer to each other through the center of nanoflower, which provides another effective way for charge transferring. Therefore, excellent charge separation and transferring ability is achieved over ZCS nanoflowers. ZnCdS solid solutions have been extensively studied due to their excellent photocatalytic hydrogen evolution performance. The change of the molar ratio of precursors affects the morphology and structure of ZnCdS, with the subsequent influence on the separation of photogenerated electron–hole pairs and the hydrogen production ability. The effect of the amount of nonmetallic elements on the photocatalytic activity has been scarcely explored. In this work, the morphology of ZnCdS is regulated by varying the amount of thioacetamide as S precursor. The structure of the samples is thoroughly analyzed by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller analysis. Their optical properties, photocatalytic hydrogen evolution ability, and photoelectrochemical performance are evaluated. Upon increasing the amount of thioacetamide, the crystallinity improves, the ZnCdS nanorods self-assemble into nanoflowers, and the number of defects decreases. The highest photocatalytic activity is achieved for a (Zn + Cd):S molar ratio of 1:3.5. Moreover, the photocatalyst exhibits excellent stability after six cycles. The one-dimensional nanorod structure contributes to the formation of a space charge region that drives the charge carriers along the nanorods. The self-assembled ZnCdS nanoflowers provide extra channels for the charge transfer, improving the separation of electron–hole pairs. [ABSTRACT FROM AUTHOR]

Loading of noble metal nanoparticles (NPs) on the surfaces of semiconductor oxides to form a hybrid nanostructure is an effective strategy to improve gas-sensing performance. In this study, WO 3 nanoplatelets decorated with Au NPs were prepared by laser ablation in liquids (LAL) with subsequent aging and annealing treatments. Results indicated that Au NPs with an average size of 7.8 ± 2.5 nm were highly dispersed on the surface of WO 3 nanoplatelets. As gas-sensing materials, the obtained Au-decorated WO 3 nanoplatelets showed lower operating temperature of 320 °C and higher response value of 3.5-fold in detecting ethanol molecules compared with pure WO 3 nanoplatelets. Moreover, Au-decorated WO 3 nanoplatelets displayed good selectivity toward ethanol compared with other tested vapors and excellent stability within several cycled measurements. These results can be ascribed to the supported Au NPs, which promote the adsorption and dissociation of oxygen species, eventually resulting in accelerated electron depletion on the surface of Au–WO 3 hybrids. [ABSTRACT FROM AUTHOR]

Self-assembly of organic molecules has attracted more and more attention because of precise molecular structure and multifarious synthesis chemistry. Herein, near-infrared brominated boron-dipyrromethenes (BODIPY) paclitaxel conjugate (BrBDP-2PTX) was synthesized. BrBDP-2PTX could self-assemble into uniform spherical nanoparticles (BrBDP-2PTX NPs) via nanoprecipition method. The obtained nanoparticles showed satisfying stability in aqueous solution and 10% fetal bovine serum (FBS) containing phosphoric acid buffer solution (PBS). Moreover, BrBDP-2PTX NPs could make rapid enzyme response to Proteinase K as evidenced by the obvious changes in size and size distribution. BrBDP-2PTX NPs could be internalized by the HeLa cells and exhibited potent cytotoxicity toward tumor cells (human cervical carcinoma cells and liver hepatocellular carcinoma cells) as revealed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assays and live/dead staining. Furthermore, in vivo experiments indicated BrBDP-2PTX NPs could be used as efficient bioimaging agents without causing any systemic toxicity. This work highlights the potential of using self-assembly of small organic molecules to develop functional nanomaterials. [ABSTRACT FROM AUTHOR]

Binary colloidal crystals (BCCs) possess great potentials in tuning material and optical properties. In this paper, the combination of interface transferred method and spin-coating method is used to fabricate BCCs with different patterns via controlling the size ratio of small (S) to large (L) colloidal spheres and the spin speeds. It is found that BCCs formed LS 2 , LS 4 and LS 6 by changing the size ratio. In addition, there are some new and complicated structures, such as LS 12 , Janus arrays, formed at the low spin speed. This simple assembly method has potential to allow for the creation of optical metmaterials and the plasmonic structures with chiral optical properties. [ABSTRACT FROM AUTHOR]

In the paper, we investigated experimentally the optical properties of disordered and binary ordered separated metal nanoparticle arrays prepared with thermal decomposing polymer particles based on self-assemble polystyrene sphere masks. The disordered metal nanoparticles and binary ordered separated metal nanoparticles with controllable size were prepared under different conditions. The size of metal nanoparticles can be effectively controlled from 200 nm to 800 nm. The intrinsic resonant properties of disordered or ordered Au nanoparticles arrays are not affected by the density or size of nanoparticles. However, the binary ordered Au nanoparticles arrays could exhibit tunable surface plasmonic resonance bands from the visible region to the near-infrared region by adjusting the size of nanoparticles. The plasmonic mechanism of these novel structures implies a promising application in surface plasmonic enhanced spectra. [ABSTRACT FROM AUTHOR]

Abstract: Self-assembled polymeric micelles can be used as efficient particulate emulsifiers. To explore the relationship between micellar structure and emulsification performance, pH- and temperature-responsive self-assembled micelles were prepared and used as emulsifiers, based on a novel grafted polymer poly(styrene-alt-maleic acid)-graft-poly(N-isopropyl acrylamide) (PSMA-g-PNIPAm). Structure of PSMA-g-PNIPAm micelles varies in response to pH and temperature changes and can be classified into four typical states, including shrunken, moderately swollen, extremely swollen, and inverted states, confirmed by a combination of electrophoresis, dynamic light scattering (DLS), transmission electron microscopy (TEM), and 1H NMR. This structural variation plays a key role in the emulsification performance of PSMA-g-PNIPAm micelles, according to the emulsifying characteristics of the four typical PSMA-g-PNIPAm micelles as well as the micellar morphologies on the surface of oil droplets as observed by SEM. Emulsions stabilised by micelles with moderately swollen structure are especially stable compared with either the shrunken micelles or the extremely swollen micelles, because the moderately swollen micelles combine the advantages of solid particulate emulsifiers and polymeric surfactants. [Copyright &y& Elsevier]

Abstract: In three strong inorganic acidic conditions (HNO3, HCl and H2SO4), we have prepared a series of air–water interfacial zirconium dioxide (ZrO2) films at normal temperature via a self-assembly technique, by using dodecylbenzenesulfonic acid (DBSA) as template and Zr(OC4H9)4 as precursor. X-ray diffraction (XRD), transmission electron microscope (TEM), UV–vis and fluorescence spectra have been used to characterize the ZrO2 films. Results show that a number of worm-like mesoporous nanodisks and ambiguously mesoporous nanodisks are observed in the ZrO2 films with and counter-ions, respectively. Remarkably, a great many perfect target-like multiring nanodisks are obtained in the ZrO2 sample with Cl− counter-ion. The self-assembly mechanism for ZrO2 nanodisks has been purposely discussed. A model based on the structural changes with respect to the influence of counter-ions on the self-assembly of ZrO2 nanodisks is therefore proposed. In addition, the structural changes for the ZrO2 films self-assembled at a higher temperature have been discussed in combination with the influence of counter-ions. [ABSTRACT FROM AUTHOR]

Abstract: We reported here the two-component self-assembling building blocks capable of forming lyotropic liquid crystal and liquid-crystalline physical gel. One of the components has a molecular characteristic of -symmetrical trisureas containing three azobenzene groups, which can form liquid-crystal phase in a temperature range of 133–215 °C. Another one has a trisamide core, which can self-aggregate to fibrous network through hydrogen bonds of amide moieties. The mixture of these two components performs lyotropic liquid crystal as well as liquid-crystalline physical gel in a temperature range larger than that of sole compound, suggesting that the cooperation of hydrogen bonds between these components stabilizes the mesophase of the assembly. The mechanism of formation of the mesophase was investigated by infrared spectra and small-angle X-ray scatterings. [Copyright &y& Elsevier]

Abstract: Nano-sized poly(ethylene glycol dimethacrylate-co-acylic acid) (poly(EGDMA-co-AA)) were effectively self-assembled on poly(divinylbenzene-co-styryl methylpyridinium chloride) (poly(DVB-co-StMPyCl)) surfaces to form the raspberry-like composite by a charge compensation mechanism through the affinity complex between carboxylic group and pyridinium group. The effects of pH and salt electrolyte on the morphology of the self-assembled polymer composites were investigated. The resulting heterocoagulates were highly stable in water and acid solution. These heterocoagulates were reversible through the self-assembly in acidic or neutral media and the dissociation in the basic medium due to the charge compensation through the strong affinity complex between hydroxide anion and pyridinium group cation. The resulting heterocoagulates were characterized with scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). As a result, a new method for tuning the structure of a charge compensation directed polymer composite was developed. [Copyright &y& Elsevier]

Abstract: Composition of nanostructured metal particles on oxide tubes (TiO2 and ZrO2) were fabricated and characterized. The composite materials were examined by transmission electron microscopy, scanning electron microscopy, FT-IR absorption, and UV–visible absorption spectra. The results of characterization showed that the composites indeed contained both oxide tubes and gold nanoparticles and that the gold nanoparticles were intimately associated with the nanotubes. [Copyright &y& Elsevier]

Eight organotin complexes have successfully prepared. In vitro antitumor activities test, C2 has high activity and selectivity for inhibiting cancer cells. • Eight organotin complexes were synthesized and characterized, and there exhibit four structural types. • Dibutyltin complex C2 has high activity and selectivity for inhibiting cancer cells. • C2 is easy to synthesize, and may be developed as a new chemotherapeutic drug due to its excellent antitumor activity. Eight organotin(IV) complexes (C1 - C8) have been synthesized and characterized by elemental analysis, fourier transform infrared spectroscopy (FT-IR), multinuclear nuclear magnetic resonance (1H, 13C and 119Sn NMR), high resolution mass spectroscopy (HRMS) and single crystal X-ray structural analysis. Crystallographic data show that C1 was a tetranuclear 16-membered macrocycle complex, C2 - C4 and C7 were centrosymmetric dimer distannoxane and there was a Sn 2 O 2 four-membered ring in the middle of the molecule, respectively, C5 and C6 are monoorganotin complexes due to the dehydroalkylation effect during the reaction, while C8 forms a one-dimensional chain structure. The cytotoxicity of all complexes were tested by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide (MTT) assays against three human tumor cell lines NCI-H460, MCF-7 and HepG2. The dibutyltin complex C2 has been shown to be more potent antitumor agents than other complexes and carboplatin. Cell apoptosis study of C2 with the high activity on HepG2 and MCF-7 cancer cell lines was investigated by flow cytometry, it was shown that the antitumor activity of C2 was related to apoptosis, but it has different cell cycle arrest characteristics from platinum compounds, and the proliferation was inhibited by blocking cells in S phase. The DNA binding activity of the C2 was studied by UV–visible absorption spectrometry, fluorescence competitive, viscosity measurements and gel electrophoresis, results shown C2 can be well embedded in the double helix of DNA and cleave DNA. [ABSTRACT FROM AUTHOR]