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Precise manipulation of the morphologies of aqueous Janus droplets by leveraging the PEG/DEX ATPS on a superhydrophobic surface.

This article presents a systematic review of emulsion gels: from fundamentals to applications.

The external field-directed assembly of nanoparticles becomes a robust method to fabricate functional materials. In this review, the effects of electric field, magnetic field, and shear field on the self-assembly of nanoparticles are highlighted.

Janus particles, having the property integration of each component, have attracted increasing attention due to their considerable potential in the field of material engineering applications. However, organic solvents or sophisticated equipment during the fabrication processes is generally inevitable. Here, we report a facile route to prepare Janus droplets and hydrogels via aqueous two-phase systems (ATPS). Simply merging two polymers, i.e., polyethylene glycol (PEG) and dextran (DEX), as aqueous droplets on a superamphiphobic surface leads to phase separation, provided that their concentrations exceed the threshold in the mixed aqueous droplets, thus generating a Janus structure. Various morphologies of such Janus droplets can be well controlled by manipulating the locations of these two polymers' concentration on the phase diagram, and the evolution of the mixed droplets are deterministic on the basis of the kinetics of their phase separation and the degree of hydrophobicity of the substrate. Introducing monomers and/or nanoparticles, further, into a certain phase of the ATPS droplet followed by photopolymerizing enables Janus hydrogel particles with diverse functionalities to be obtained. The ease and green techniques with which the Janus balance and curvature between two phases of the Janus droplet can be finely tuned point to new directions in designing Janus particles and hold great promises in biological engineering.

To simultaneously detect whole transcriptomes and protein markers on the same tissue section, we combined Cellular Indexing of Transcriptomes and Epitopes by Sequencing (CITE-seq) and Stereo-seq to develop the Stereo-CITE-seq workflow. Here, we demonstrated that Stereo-CITE-seq can co-detect mRNAs and proteins in immune organs with high spatial resolution, reproducibility and accuracy.

Spatial Transcriptomics (ST) technology enables systematic depiction of regional milieu of a tissue, like tumor immuno-microenvironment (iTME). However, a powerful algorithmic framework to dissect spatially resolved niches, and to quantitatively evaluate spatial cell interaction intensity will pave the ways to understand the spatial signature associated mechanism. In this study, we provide a promising framework (StereoSiTE), which is based on space nearest neighbor graph and gene expression profile to spatially resolve iTME and to quantitatively define cell-cell communication intensity. We applied StereoSiTE to dissect the iTME of xenograft model receiving immunoagonist treatment, 7 distinct cellular neighborhoods (CN) were identified, and each CN was considered as the functional unit with exclusive cell type (CT) composition. Further deconvolving the joint matrix covering CNs and CTs indicated the importance of neutrophils in CN6, which was confirmed by pathway enrichment analysis. What’s more, analysis of interaction intensity indicated that the recruited neutrophils preserved tumor protection activity through paired IL-1β/IL-1R after immunoagonist treatment exclusively in CN6. This evidence provided a new possible vision of tumor immune evasion orchestrated by neutrophils. StereoSiTE is believed to be a promising framework of mapping iTME niches using spatial transcriptomics, which could be utilized to spatially reveal tumoribiology mechanisms.HighlightA framework based on space nearest neighbor graph and gene expression profile to spatially resolve iTME and to quantitatively define cell-cell communication intensity (StereoSiTE)

Novel urethane ionic groups were incorporated into biodegradable poly(ethylene succinate) (PES) by chain extension reaction of PES diol (HO-PES-OH) and diethanolamine hydrochloride (DEAH) using hexamethylene diisocyanate (HDI) as a chain extender. The synthesized polymer was a novel segmented poly(ester urethane) ionomer (PESI) in which the soft segments were formed by reaction of HO-PES-OH with HDI and the hard segments that contained ionic groups were derived from reaction of DEAH with HDI. The crystallization rate of PESI was dramatically accelerated when 3 mol % urethane ionic groups were incorporated. However, the crystallization mechanism did not change. The significant acceleration in crystallization rate was attributed to the improved nucleation efficiency by incorporation of the urethane ionic group, because PESI showed significantly enhanced nucleation density but slightly slowed spherurlitic growth rate in comparison with PES which was synthesized by chain extension reaction of HO-PES-OH with HDI. The increased nucleation efficiency was ascribed to the aggregation of hard segments of PESI induced by the ionic interactions.

Emulsion as a fine dispersion of immiscible liquids has involved widespread applications in industry, pharmaceuticals, agriculture, and personal care. Stimuli-responsive emulsions capable of on-demand demulsification or changing their properties are required in many cases such as controllable release cargo, oil recovery, emulsifier recycling, and product separation, great progress is achieved in these areas. Among these various triggers, much effort is made to develop physical stimuli, due to the noninvasive and environmentally friendly characteristics. Physical stimuli-responsive emulsions provide plenty of valuable practical applications in the fields of sustainable industry, biomedical reaction, drug delivery. Here, the recent development in the field of emulsions in response to physical stimuli consisting of temperature, light, magnetic fields, electrical fields, etc., is summarized. The preparation methods and mechanisms of physical stimuli-responsive emulsions and their applications of catalysis reaction, drug delivery, and oil recovery are highlighted in this review. The future directions and outstanding problems of the physical stimuli-responsive emulsions are also discussed.

The substitution of petroleum-based self-healing elastomers with biobased counterparts is crucial to the global sustainable development of the rubber industry, which highly depends on the ease of t...

Monodispersed hairy nanocomposites with typical 2 nm (isophthalic acid)24 Cu24 metal-organic polyhedra (MOP) as a core protected by 24 polymer chains with controlled narrow molecular weight distribution has been probed by imaging and scattering studies for the heterogeneity of polymers in the nanocomposites and the confinement effect the MOPs imposing on anchored polymers. Typical confined-extending surrounded by one entanglement area is proposed to describe the physical states of the polymer chains. This model dictates the counterintuitive thermal and rheological properties and prohibited solvent exchange properties of the nanocomposites, whilst those polymer chain states are tunable and deterministic based on their component inputs. From the relationship between the structure and behavior of the MOP nanocomposites, a MOP-composited thermoplastic elastomer was obtained, providing practical solutions to improve mechanical/rheological performances and processabilities of inorganic MOPs.

Hydrophilic PEGylated porous self-assembled nanomembranes (PSANMs) with average thickness and pore diameter of ca. 10 and 20-24 nm were successfully prepared by an emulsification-induced programmable self-assembly strategy. The hydrophilicity, anti-biofouling, and anti-thrombosis properties of PEGylated PSANMs were largely improved in comparison with the nonfunctionalized PSANMs, which could transform into hydrophilic (PEGylated PSANMs, minimum water contact angle: 38.8°) from hydrophobic units (PSANMs, maximum water contact angle: 137.5°) with increasing PEG density and length. The total protein adsorption of PEGylated PSANMs was about six times lower than that of the PSANMs, while the thrombosis of the PEGylated PSANMs (maximum R-time: 5.37 min) was also greatly relieved in comparison with the PSANMs (minimum R-time: 2.93 min). Such PEG-modified PSANMs may have applications in drug delivery and tissue and organ repair in vivo.

Triptolide (TP) has been widely used in clinical medicine; however, it has created a dilemma due to its toxicity and nonspecificity. Here, we reported a biocompatible and high-efficiency renal-targeting nanoplatform for renal ischemia/reperfusion injury (IRI) therapy, in which the toxic drug of TP was encapsulated into folate (FA)-modified Pluronic F127/P123 nanoparticles (FPNPs). The TP-loaded FPNPs (TP-FPNPs) had good stability and could effectively reduce the cytotoxicity of TP. Compared with the Pluronic nanoparticles (PNPs) group, cellular uptake ability of FPNPs significantly improved because of folate receptor-mediated endocytosis effect. Ex vivo organ imaging and pharmacokinetic results indicated that FPNPs possessed high kidney selectivity and long retention time. The therapeutic effect of TP-FPNPs on renal IRI was more superior to that of free TP, such as lower acute tubular injury index (2.9-fold), renal function indexes of serum creatinine (4.3-fold), urea nitrogen (2.0-fold), and Western blotting (2.4-fold). Systemic toxicity assay suggested that TP-FPNPs had much lower nephrotoxicity, hepatotoxicity, and genital system toxicity than free TP. Thus, renal-targeting FPNPs will be a potential delivery platform of hydrophobic drugs for treatment of renal diseases.

BDNF-to-TrkB signaling pathways plays an important role in the long-term maintenance of the nigrostriatal system and that its deficiency may contribute to the onset and progression of Parkinson's disease (PD). To our knowledge this is the first study to investigate the expression of the brain-derived neurotrophic factor (BDNF) and phosphorylation status of TrkB in peripheral blood lymphocytes of 28 PD and 28 Essential tremor (ET) patients and 28 healthy controls using western blot analysis. Compared with controls, no significant difference of BDNF and total and phosphorylated TrkB levels were observed in ET, whereas BDNF and phosphorylated TrkB levels were significantly decreased in the PD groups (p 0.001). Interestingly, BDNF and phosphorylated TrkB levels were positively correlated with disease duration, UPDRS score, Hoehn-Yahr staging, as well as L-DOPA medication in PD patients. These results suggest that the decreased peripheral alteration of BDNF/TrkB levels found in patients with PD is directly related to the dopaminergic neurons neurodegeneration and that decreased expression of BDNF/TrkB may lead to the development of innovative biomarkers of PD, whereas the increased level of BDNF and phosphorylated TrkB at advanced stages may due to L-DOPA medication.

Granular materials, composed of densely packed particles, are known to possess unique mechanical properties that are highly dependent on the surface structure of the particles. A microscopic understanding of the structure-property relationship in these systems remains unclear. Here, supra-nanoparticle clusters (SNPCs) with precise structures are developed as model systems to elucidate the unexpected elastic behaviors. SNPCs are prepared by coordination-driven assembly of polyhedral oligomeric silsesquioxane (POSS) with metal-organic polyhedron (MOP). Due to the disparity in sizes, the POSS-MOP assemblies, like their classic nanoparticles counterparts, ordering is suppressed, and the POSS-MOP mixtures will vitrify or jam as a function of decreasing temperature. An unexpected elasticity is observed for the SNPC assemblies with a high modulus that is maintained at temperatures far beyond the glass transition temperature. From studies on the dynamics of the hierarchical structures of SNPCs and molecular dynamic simulation, the elasticity has its origins in the interpenetration of POSS-ended arms. The physical molecular interpenetration and inter-locking phenomenon favors the convenient solution or pressing processing of the novel cluster-based elastomers.

To evaluate the diagnostic value of serum Brain-derived neurotrophic factor (BDNF) levels for discriminating PD with depression from without depression, and to investigate whether serum BDNF levels were associated with motor severity and gender in depressed PD patients.Demographic and clinical data were collected from 122 PD patients with depression, 137 without depression and 110 healthy controls. All participants' serum BDNF concentrations were measured. Their motor abilities and activity were assessed by the Unified PD Rating Scale Part III (UPDRS III) score and the Hoehn and Yahr (H-Y) stage. Depression was scored using the 17-item Hamilton Rating Scale for Depression (HAMD-17). Associations were analyzed with multivariate regression.The serum BDNF levels were lower in depressed PD patients compared to non-depressed PD patients and controls (p 0.001). The BDNF levels were negatively correlated with UPDRS III score (r = - 0.54, p 0.001) and H-Y stage (r = - 0.45, p 0.001). Decreased BDNF levels were associated with women only among depressed PD patients (r = 0.45, p 0.001). The HAMD-17 score was negatively correlated with BDNF levels (r = - 0.59, p 0.001), and positively associated with UPDRS III score (r = 0.51, p 0.001). Multiple regression analysis demonstrated that in the depressed PD patients, female, H-Y stage and UPDRS III score were independent contributors to the BDNF levels (p 0.001; p = 0.006; p = 0.03, respectively), BDNF and UPDRS III score were independent contributors to HAMD-17 score (p 0.001, p = 0.01, respectively).Decreased serum BDNF levels may be a useful clinical biomarker of depression in PD patients. Serum BDNF may serve as a potential biomarker for motor severity of PD patients with depression, especially in female.

Spinodal decomposition is not the only way to make a bijel. Indeed, while spinodal decomposition produces structures with a potentially useful morphology, it can be challenging to make bijels using this method and the resulting systems can be hard to process and manipulate. Furthermore, exploiting the functional properties of the assembled particle monolayer is extremely challenging. In this chapter, we show how the assembly of nanoparticle surfactants at the liquid–liquid interface can be used to kinetically trap liquids into a wealth of complex structures without using spinodal decomposition. We apply liquid three-dimensional printing and moulding methods, along with patterned substrates with controllable wetting properties, to build all-liquid devices with applications in chemical synthesis, separation, and purification. The functional properties of the assembled nanomaterials can be exploited to produce interfacially structured liquids that are plasmonically and magnetically responsive. Finally, we conclude by arguing that, while the field shows great promise, efforts need to be made to translate liquid bicontinuous systems out of the laboratory and into meaningful, real-world applications, as well applications in more ‘exotic’ disciplines, such as synthetic biology.

Bad water solubility and undesired toxicity of triptolide (TP) still restrict its clinical applications in renal diseases. In this work, well-defined, monodispersed, and uniform-sized TP-encapsulated mesoscale nanoparticles (TP-MNPs) were fabricated through a nanoprecipitation method, which possesses special kidney-targeting capacity, slow-release property, and high-efficiency treatment for renal ischaemia-reperfusion injury (IRI). The TP-MNPs had good cytocompatibility in wide TP concentration (0-500 ng ml-1) and time ranges (6-24 h). Ex vivo organ fluorescence imaging and pharmacokinetic analysis suggested that TP-MNPs possessed excellent kidney-targeting capability with long retention time (7 days). The TP-MNPs with a very low dose of TP (0.01 mg kg-1) could effectively protect the kidney against IRI, while 0.01 mg kg-1 TP was completely ineffective. After treatment with TP-MNPs, the serum creatine, blood urea nitrogen, expression of C3 complement, and phospho-extracellular signal-regulated kinase of renal IRI mice were estimated to be 5.9-, 2.0-, 5.4-, and 2.8-fold lower than those of the mice treated with TP, respectively. Compared with TP, the TP-MNPs exhibited ignorable hepatotoxicity, reproductive toxicity, and immunotoxicity, such as lower alanine aminotransferase (0.5 fold) and aspartate aminotransferase (0.2 fold), and a higher ratio of CD4+/CD8+ (2.2 fold). Thus, the monodispersed and uniform-sized TP-MNPs with special kidney-targeting and slow-release property may pave an avenue for designing a new therapeutic strategy for renal diseases.

Metal oxides with high porosity usually exhibit better performance in many applications, as compared with the corresponding bulk materials. Template-assisted method is generally employed to prepare porous metal oxides. However, the template-assisted method is commonly operated in wet conditions, which requires solvents, soluble metal oxide precursors, and a long time for drying. To overwhelm those drawbacks of the wet procedure, a mechanochemical nanocasting method is developed in the current work. Inspired by solid-state synthesis, this strategy proceeds without solvents, and the ball milling process can enable pores replicated in a shorter time (60 min). By this method, a series of highly porous metal oxides were obtained, with several cases approaching the corresponding surface area records (e.g., ZrO2, 293 m2 g–1; Fe2O3, 163 m2 g–1; CeO2, 211 m2 g–1; CuOx-CeOy catalyst, 237 m2 g–1; CuOx-CoOy-CeOz catalyst, 203 m2 g–1). Abundant nanopores with clear lattice fringes in metal oxide products were witnesse...

A simple and versatile strategy, borrowing ideas from the chemistry of MOFs and COFs, is developed for the synthesis of coordination-supported organic polymers (COPs) via coordination between Al3+ and 5-amino-8-hydroxyquinoline together with organic imine- or imide-based polycondensation. The COPs with high surface areas (up to 1123 m2 g−1) and abundant mesopores (2.5 nm or 14 nm) possess good crystalline and porous structure after being soaked in boiling water.

Background The majority of the coronavirus disease 2019 (COVID-19) non-survivors meet the criteria for disseminated intravascular coagulation (DIC). Although timely monitoring of clotting hemorrhagic development during the natural course of COVID-19 is critical for understanding pathogenesis, diagnosis, and treatment of the disease, however, limited data are available on the dynamic processes of inflammation/coagulopathy/fibrinolysis (ICF). Methods We monitored the dynamic progression of ICF in patients with moderate COVID-19. Out of 694 COVID-19 inpatients from 10 hospitals in Wenzhou, China, we selected 293 adult patients without comorbidities. These patients were divided into different daily cohorts according to the COVID-19 onset-time. Furthermore, data of 223 COVID-19 patients with comorbidities and 22 critical cases were analyzed. Retrospective data were extracted from electronic medical records. Results The virus-induced damages to pre-hospitalization patients triggered two ICF fluctuations during the 14-day course of the disease. C-reactive protein (CRP), fibrinogen, and D-dimer levels increased and peaked at day 5 (D) 5 and D9 during the 1st and 2nd fluctuations, respectively. The ICF activities were higher during the 2nd fluctuation. Although 12-day medication returned high CRP concentrations to normal and blocked fibrinogen increase, the D-dimer levels remained high on days 17 ± 2 and 23 ± 2 days of the COVID-19 course. Notably, although the oxygenation index, prothrombin time and activated partial thromboplastin time were within the normal range in critical COVID-19 patients at administration, 86% of these patients had a D-dimer level > 500 μg/L. Conclusion COVID-19 is linked with chronic DIC, which could be responsible for the progression of the disease. Understanding and monitoring ICF progression during COVID-19 can help clinicians in identifying the stage of the disease quickly and accurately and administering suitable treatment.

Conventional superhydrophobic materials for oil/water separation were usually prepared from nondegradable and nonrenewable resources, which would not only increase resource crisis but also cause environmental pollution after discarding. In this study, we report a renewable and biodegradable superhydrophobic material, which was fabricated via a two-step curing dip-coating method and was composed of cellulosic filter paper or fabric, cured epoxidized soybean oil (CESO), ZnO, and stearic acid (STA) as the substrate, adhesive, rough structure, and low energy modifier, respectively. The CESO combined ZnO nanoparticles with cellulosic substrate tightly to show excellent stability when suffering from immersing in water and oil for 7 days without losing superhydrophobicity. When the superhydrophobic coating was constructed onto the surface of cellulosic fabric, the material showed high separation efficiency with the values higher than 97% during separation of various oil/water mixtures. The sustainable and biodeg...

© 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Bicontinuous jammed emulsions (or bijels) are tortuous, interconnected structures of two immiscible liquids, kinetically trapped by colloidal particles that are irreversibly bound to the oil-water interface. A wealth of applications has been proposed for bijels in catalysis, energy storage and molecular encapsulation, but large domain sizes (on the order of 5 μm or larger) and difficulty in fabrication pose major barriers to their use. Here, we show that bijels with sub-micrometre domains can be formed via homogenization, rather than spinodal decomposition. We achieve this by using nanoparticle surfactants: polymers and nanoparticles of complementary functionality (for example, ion-pairing) that bind to one another at the oil-water interface. This allows the stabilization of the bijel far from the demixing point of the liquids, with interfacial tensions on the order of 20 mN m-1. Furthermore, our strategy is extremely versatile, as solvent, nanoparticle and ligand can all be varied.

The controlled structuring of liquids into arbitrary shapes can be achieved in biphasic liquid media using the interfacial assemblies of nanoparticle surfactants (NP-surfactants), that consist of a polar nanoparticle "head group" bound to one or more hydrophobic polymer "tails". The nonequilibrium shapes of the suspended liquid phase can be rendered permanent by the jamming of the NP-surfactants formed and assembled at the interface between the liquids as the system attempts to minimize the interfacial area between the liquids. While critical to the structuring process, little is known of the dynamic mechanical properties of the NP-surfactant monolayer at the interface as it is dictated by the characteristics of the component, including NP size and concentration and the molecular weight and concentration of polymers bound to the NPs. Here we provide the first comprehensive understanding of the dynamic mechanical character of two-dimensional NP-surfactant assemblies at liquid/liquid interfaces. Our results indicate that the dynamics of NP-polymer interactions are self-regulated across multiple time scales and are associated with specific mesoscale interactions between self-similar and cross-complementary components. Furthermore, the mechanical properties of the NP-surfactant monolayer are tunable over a broad range and deterministic on the basis of those component inputs. This control is key to tailoring the functional attributes of the reconfigurable structured liquids to suit specific applications.

The poor water stability of most porous coordination polymers (PCPs) or metal-organic frameworks (MOFs) is widely recognised as a barrier hampering their practical applications. Herein, a facile and scalable route to prepare metal-containing polymers with a good stability in boiling water (100oC, 24 h) and air (up to 390oC) is presented. The bifunctional 1-vinylimidazole (VIm) with both a coordinating site and a polymerizable organic group is introduced as the building block. This core strategy includes the synthesis of a rigid monomer with four VIm branches via a coordination process at room temperature, followed by a radical polymerization. Here we call this material Coordination-supported Imidazolate Networks (CINs). Interestingly, CINs are composed of rich mesopores from 2 to 15 nm, as characterized by low-energy (60 kV) STEM-HAADF images. Especially, the stable CINs illustrate a high turnover frequency (TOF) of 779 h-1 in the catalytic oxidation of phenol with H2O as the green solvent.

Living anionic polymerization of acrylates is challenging due to intrinsic side reactions including backbiting reactions of propagating enolate anions and aggregation of active chain ends. In this study, the controlled synthesis of poly(1-adamatyl acrylate) (PAdA) was performed successfully for the first time via living anionic polymerization through investigation of the initiation systems of sec-butyllithium/diphenylethylene/lithium chloride (sec-BuLi/DPE/LiCl), diphenylmethylpotassium/diethylzinc (DPMK/Et2Zn), and sodium naphthalenide/dipenylethylene/diethylzinc (Na-Naph/DPE/Et2Zn) in tetrahydrofuran at −78 °C using custom glass-blowing and high-vacuum techniques. PAdA synthesized via anionic polymerization using DPMK with a large excess (more than 40-fold to DPMK) of Et2Zn as the ligand exhibited predicted molecular weights from 4.3 to 71.8 kg/mol and polydispersity indices of around 1.10. In addition, the produced PAdAs exhibit a low level of isotactic content (mm triads of 2.1%). The block copolymers...

Shape memory polymers (SMPs) have the capacity of memorizing a temporary shape and recovering their initial shape in response to various external stimuli. As one of promising class of intelligent materials, it has attracted great attention because of its potential applications in many areas, such as biomaterials and biotechnology, automotive industry, and aerospace field. Aliphatic polymers play an important role in the molecular design of SMPs owing to its excellent biodegradability and biocompatibility, and suitable thermal transition temperature range. This review focuses on the recent progress of shape memory polymers based on the aliphatic polyesters such as poly(lactic acid) (PLA), poly ( p -dioxanone) (PPDO), poly(butylene succinate) (PBS), poly( ω -pentadecalactone) (PPDL) and poly( ɛ -caprolactone) (PCL) and so on. From the view of architecture design, different systems are classified by block copolymers, crosslinking networks and interpenetrating networks. The influence of architectural features on the shape memory behaviors is also discussed. The block copolymers have been identified a typical mature system in design of dual-shape material, and the crystalline aliphatic polyesters can be served as the netpiont or the molecular switch in a SMP, depending on its transition temperature range among the binary systems. The thermoplastic feature of block copolymers endows an easy processibility. The various architectures of crosslinking network meet the increasing demand of SMPs design. Constructing network with crystallizable polyester segment such as PCL may achieve SMPs in one-way and two-way mode, and the stress-free two-way mode can also be realized by an elaborate architecture with pre-programed treatment. Embedding two segments in one network may achieve a triple-shape memory effect, meanwhile, incorporating two segments in an interpenetrating polymer network may result in a triple-shape material with improved performance. Recently, the SMPs based on dynamic networks become the new trend, which may combine the self-healing with shape memory effect in one system, and both dynamic covalent bond and non-covalent bond have been concerned. In order to fulfill the increasing requirement of application, the SMPs with multi-shape memory effect, multi-responsibility and multi-functionality are highly expected.

In the past decades, ceria-based materials have been well developed as catalysts for complete oxidation; however, only a very few studies have involved ceria-promoted selective oxidations. Herein, porous transition-metal-salt–doped ceria (TMS@CeO2) materials (up to 455 m2/g) were fabricated by a simple, general co-assembly strategy with ionic liquids as recyclable templates. The TMS@CeO2 catalyst was found to be active in the selective oxidation of sulfides to sulfoxides/sulfones by molecular oxygen. It is interesting that the TMS doping significantly increases the catalytic performance of the original ceria catalyst and, surprisingly, the TMS@CeO2 catalyst showed much higher activity than a transition metal–doped cerium oxide solid solution. The TMS and CeO2 are supposed to synergistically activate O2 at the interface. It is believed that the abundant ceria-based materials will provide more efficient catalysts for controlled oxidation in the near future.

Using a bidirectional freezing technique, combined with uniaxial pressing and in situ polymerization, "nacre-mimetic" hydroxyapatite/poly(methyl methacrylate) (PMMA) composites are developed by processing large-scale aligned lamellar ceramic scaffolds. Structural and mechanical characterization shows "brick-and-mortar" structures, akin to nacre, with interesting combinations of strength, stiffness, and work of fracture, which provide a pathway to making strong and tough lightweight materials.

Enhancing matrix crystallization via forming stereocomplex (SC) crystallite has been considered as an effect way to improve the impact toughness and heat resistance of poly( l -lactide) (PLLA) when blending with other polymers. However, the roles of some of the key parameters, such as the kinetics of morphology evolution in blends, remain, yet, unclear, causing the troubles of the reproducibility of toughening PLLA by enhancing matrix crystallization and the stability in end-use applications (particularly in relative high temperature ranges). Herein, we provide a facile way to improve the toughness and heat resistance of PLLA via engineering the balance between the kinetics and thermodynamics of the dispersed phasic morphology in PLLA blends using PLLA/poly(e-caprolactone) (PCL) (PLLA/PCL, 80/20 w/w) as an example, by adding a small amount of poly( d -lactide) (PDLA, ≤ 1% w/w). The few PDLA chains naturally interact with PLLA matrix chains, and co-crystallize to form SC crystallites, yielding high crystalline PPLA matrix but in controllable crystallization kinetics and increase of melting viscosity. As such, the coalescence or arrest of dispersed PCL phase is tailored via the tempo- and thermo-dimensional balance manipulation of thermal annealing (thermodynamics) and injecting moulding (quenching, dynamics), that relies on the PDLA content. The ease, with which highly impact toughened and heat-resistant PLLA materials were obtained by optimizing and matching the PDLA content and processing parameters including temperature and time, points to new directions in designing toughened PLLA with an economic manner.

A framework is presented to control phase transformations in colloidal nanocrystal assemblies at liquid-liquid interfaces., Mesostructured matter composed of colloidal nanocrystals in solidified architectures abounds with broadly tunable catalytic, magnetic, optoelectronic, and energy storing properties. Less common are liquid-like assemblies of colloidal nanocrystals in a condensed phase, which may have different energy transduction behaviors owing to their dynamic character. Limiting investigations into dynamic colloidal nanocrystal architectures is the lack of schemes to control or redirect the tendency of the system to solidify. We show how to solidify and subsequently reconfigure colloidal nanocrystal assemblies dimensionally confined to a liquid-liquid interface. Our success in this regard hinged on the development of competitive chemistries anchoring or releasing the nanocrystals to or from the interface. With these chemistries, it was possible to control the kinetic trajectory between quasi–two-dimensional jammed (solid-like) and unjammed (liquid-like) states. In future schemes, it may be possible to leverage this control to direct the formation or destruction of explicit physical pathways for energy carriers to migrate in the system in response to an external field.

Polyoxometalates (POMs) using {Mo72V30} as an example, dissolved in water, can interact with amine-terminated polydimethylsiloxane (PDMS-NH2) dissolved in toluene at the water/toluene interface to form POM-surfactants that significantly lower the interfacial tension and can be used to stabilize liquids via interfacial elasticity. The jamming of the POM-surfactants at the water/oil interface with consequent wrinkling occurs with a decrease in the interfacial area. The packing density of the POM-surfactants at the interface can be tuned by varying the strength of screening with the addition of cations with differing hydrated radii.

Background and Purpose The aim of this study was to determine the potency and molecular mechanism of action of YM155, a first-in-class survivin inhibitor that is currently under phase I/II clinical investigations, in various drug-resistant breast cancers including the oestrogen receptor positive (ER+) tamoxifen-resistant breast cancer and the caspase-3-deficient breast cancer. Experimental Approach The potency of YM155 in SK-BR-3, MDA-MB-231, MCF7 and its tamoxifen-resistant sublines, TamR6, TamR7, TamR8, TamC3 and TamC6, were determined by MTT assay. Western blot analysis, flow cytometric analysis, reverse transcription-PCR, fluorescent microscopy and comet assay were used to determine the molecular mechanism of action of YM155 in different breast cancer cell lines. Key Results YM155 was equally potent towards the parental ER+/caspase-3-deficient MCF7 breast cancer cells and its tamoxifen-resistant sublines in vitro. The ER−/HER2+ SK-BR-3 breast cancer cells and the triple-negative/caspase-3-expressing metastatic aggressive MDA-MB-231 breast cancer cells were also sensitive to YM155 with IC50 values in the low nanomolar range. Targeting survivin by YM155 modulated autophagy, induced autophagy-dependent caspase-7 activation and autophagy-dependent DNA damage in breast cancer cells. Interestingly, YM155 also induced XIAP degradation and the degradation of XIAP might play an important role in YM155-induced autophagy in breast cancer cells. Conclusions and Implications YM155 is a potent survivin inhibitor that has potential for the management of various breast cancer subtypes regardless of the expression of ER, HER2 and caspase-3. Importantly, this study provides new insights into YM155's molecular mechanism of action and therapeutic potential in the treatment of tamoxifen-resistant breast cancer.

Ordered mesoporous carbons (OMCs) have demonstrated great potential in catalysis, and as supercapacitors and adsorbents. Since the introduction of the organic–organic self-assembly approach in 2004/2005 until now, the direct synthesis of OMCs is still limited to the wet processing of phenol-formaldehyde polycondensation, which involves soluble toxic precursors, and acid or alkali catalysts, and requires multiple synthesis steps, thus restricting the widespread application of OMCs. Herein, we report a simple, general, scalable and sustainable solid-state synthesis of OMCs and nickel OMCs with uniform and tunable mesopores (∼4–10 nm), large pore volumes (up to 0.96 cm3 g−1) and high-surface areas exceeding 1,000 m2 g−1, based on a mechanochemical assembly between polyphenol-metal complexes and triblock co-polymers. Nickel nanoparticles (∼5.40 nm) confined in the cylindrical nanochannels show great thermal stability at 600 °C. Moreover, the nickel OMCs offer exceptional activity in the hydrogenation of bulky molecules (∼2 nm)., Ordered mesoporous carbons have shown promise in a range of applications, but sustainable methods to achieve their large scale production are lacking. Here, Dai and coworkers produce OMCs via the mechanochemical assembly of non-toxic polyphenol-metal complexes and triblock copolymers, followed by pyrolysis.

The self-assembly and interfacial jamming of spherical Janus nanoparticles (JNPs) at the water/oil interface were investigated. Polymeric JNPs, made by cross-linking polystyrene-block-polybutadiene-block-poly(methyl methacrylate) (PS-PB-PMMA), with a high interfacial activity assemble at the water/oil interface. During the self-assembly at the interface, the interfacial energy was reduced and a dynamic interlayer was observed that is responsive to the pH of the aqueous phase. Unlike hard particles, the JNPs are composed of polymer chains that can spread at the liquid-liquid interface to maximize coverage at relatively low areal densities. In a pendant drop geometry, the interfacial area of a water droplet in oil was significantly decreased and the JNPs were forced to pack more closely. Entangling of the polymer chains causes the JNPs to form a solid-like interfacial assembly, resulting in the formation of wrinkles when the interfacial area is decreased. The wrinkling behavior, the retention of the wrinkles, or the slow relaxation of the liquid drop back to its original equilibrium shape was found to depend upon the pH.

To obtain an excellent comprehensive performance of poly(ethylene succinate) (PES), we have synthesized a series of poly(ethylene succinate) (PES) urethane ionenes (PESUIs) with various content of urethane ionic group by the chain extension reaction of dihydroxyl-terminated poly(ethylene succinate) and diethanolamine hydrochloride with hexamethylene diisocyanate as a chain extender, and we systematically investigated the composition dependence of the physico-chemical properties of PESUI through a series of characteristic techniques. The results of thermal and crystallization behaviors suggest that the incorporation of urethane ionic group slightly affects the glass transition temperature, melting temperature, and thermal stability, and significantly accelerates the crystallization rate of PES without changing the crystallization mechanism. The fastest crystallization rate was reached with the incorporation of 4 mol% urethane ionic groups. Spherulitic morphology observation indicates that nucleation density significantly increased, while spherulitic growth rate gradually decreased with increase in urethane ionic group content. Both complex viscosity and storage modulus initially increased and then decreased with increase in urethane ionic group content, and their maximum values were observed for the sample with 4 mol% of urethane ionic group. Mechanical properties slightly varied with urethane ionic group content.

The segmented poly(butylene succinate) urethane ionenes (PBSUI) containing secondary amine cation were synthesized by chain extension reaction of dihydroxyl terminated poly(butylene succinate) and diethanolamine hydrochloride (DEAH) in the presence of hexamethylene diisocyanate. NMR, DSC, WAXD, POM, SAXS, DMA, and rotational rheometer were used to characterize the structure and properties of the PBSUI, and the tensile properties and hydrolytic degradation of the PBSUI were also investigated. All the results suggest that the content of urethane ionic group plays an important role in tuning the properties of the PBSUIs. The crystallization rate increased first and then decreased and the equilibrium melting temperature increased gradually with increasing urethane ionic group content. The maximum crystallization rate was obtained for PBSUI with 3 wt% DEAH. The obvious clusters formed by aggregation of urethane ionic group were evidenced by DMA and SAXS for the PBSUI containing 5 wt% DEAH. The complex viscosity increased significantly with increasing urethane ionic group content due to the physical crosslinking effect resulted from aggregation of ionic groups. The storage modulus increased with DEAH content increased up to 3 wt %, while decreased with further increasing DEAH content. Tensile testing indicated incorporation of urethane ionic group did not change the tensile properties apparently. The hydrolytic degradation rate of the samples increased with the increase in urethane ionic group content which was mainly ascribed to the increased hydrophilicity.

Poly(butylene succinate-co-diethylene glycol succinate) (P(BS-co-DEGS)) random copolymer was synthesized and characterized in a previous paper [Ind. Eng. Chem. Res. 2012, 51, 12258−12265]. In this paper, we focus on the isothermal crystallization behaviors of P(BS-co-DEGS). The isothermal crystallization kinetics, spherulitic morphology, and growth kinetics of P(BS-co-DEGS) were investigated by differential scanning calorimetry and polarized optical microscopy and compared with those of neat poly(butylene succinate) (PBS). The results suggest that the crystallization rate of P(BS-co-DEGS) was much slower than that of neat PBS and decreased with increase of DEGS content, while the crystallization mechanism remain unchanged. P(BS-co-DEGS) showed banded morphology, and the band spacing decreased with increase of DEGS content at a given supercooling. The spherulitic growth rate of P(BS-co-DEGS) decreased with increase in DEGS content. A transition from crystallization regime II to crystallization regime III o...

Biodegradable poly(p-dioxanone) (PPDO)/synthetic hectorite nanocomposites were successfully prepared by in-situ ring-opening polymerization of p-dioxanone (PDO) in the presence of organomodified synthetic hectorite (OSHEC). Attachment of poly(ester-ether) chains around the exfoliated clay sheets was found. Influence of clay content on thermal behavior was studied. OSHEC accelerated the thermal degradation of the ester group in the polymer chains. Exfoliated organoclay layers, to some extent, acted as a hindrance to the growth rate of the spherulites instead of as nucleating agents. Inorganic clay played an important role in enhancing the shear viscosity of nanocomposites due to its unique structure and the reasonable interaction between the clay and PPDO matrix.

Through pH-tuning of electrostatic interactions between polymer ligands and nanoparticles at structured-liquid interfaces, liquid droplets can be directed between a jammed nonequilibrium state and a dynamic reconfigurable state. The nanoparticle-surfactant dynamics highly depend on the pH, so that the liquids can be structured using an external field and under variation of pH, or alternatively being realized by remote photo-triggering.

Diethylene glycol was incorporated into poly(butylene succinate) (PBS) to form biodegradable poly(butylene succinate-co-diethylene glycol succinate) (P(BS-co-DEGS)) copolymer through a two-step pro...

The crystallization kinetics, morphology and crystal structure of biodegradable double crystalline poly(butylene succinate)-poly(ethylene glycol) (PBS-PEG) multiblock copolymers (PBSEGs) were studied with different composition and segment chain length by differential scanning calorimetry (DSC), polarized optical microscopy (POM) and wide-angle X-ray diffraction (WAXD). The isothermal crystallization kinetics results show that the overall crystallization rate and the equilibrium melting point of PBS increase with the increasing PBS fraction and the segment chain length ( L PBS ); on the other hand, the higher content or longer PEG segment within PBSEGs possesses larger crystallization rate of PEG chains. The nucleation mechanisms are demonstrated to be instantaneous 3D and 2D aggregates for PBS and PEG segments within PBSEGs, respectively (except for PBSEG 2 K − 50 , 2D and 3D aggregates for PBS and PEG segments, respectively). POM observations indicate that the PBS within PBSEG multiblock copolymers presents banded spherulites in the investigated temperature range. After quenched to lower temperature, PBS templates the morphology for PEG crystallization, and PEG crystallization just changes the magnitude of birefringence (lighting the spherulites) but not influences the superstructure. Finally, WAXD measurements determine that the crystal structure is not changed with the compositions.

Poly( l -lactic acid) (PLLA) is regarded as one of the most promising biobased and biodegradable polymers. However, its application was restricted due to the brittle nature. In the present study, PLLA was blended with a novel biodegradable flexible multiblock copolymer, poly(butylene succinate-b-ethylene succinate) (PBES) to produce new biodegradable materials. PLLA/PBES blends with different composition were prepared by solution blending and casting method with chloroform as a mutual solvent. Miscibility, crystallization behavior, and mechanical properties of the blends were investigated by differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), and tensile tests. The results indicated that PLLA and PBES showed limited miscibility in the amorphous phase. The crystallization rate of PLLA was accelerated with the increase of PBES in the blends while the crystallization mechanism did not change. The results of tensile tests suggest that the blends showed longer elongation at break than neat PLLA. The elongation at break of PLLA was obtained to be 10%, and those of PLLA/PBES 80/20, 60/40, 40/60 and 20/80 were 29, 110, 442, and 455%, respectively.

Biodegradable multiblock copolymers poly(butylene succinate-b-poly(ethylene glycol) succinate) (P(BS-b-PEGS)) were prepared by direct polycondensation. The thermal and crystallization behavior of P(BS-b-PEGS) with weight fraction of PEGS component from 6 to 26 wt % were comparatively investigated with those of neat poly(butylene succinate) (PBS) by wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), and polarized optical microscopy (POM). P(BS-b-PEGS) showed the same crystal structure as neat PBS, but the degree of crystallinity of copolymers was lower than that of neat PBS and decreased with increase in PEGS content. The isothermal crystallization kinetics study suggests that incorporation of PEGS component did not change the crystallization mechanism, but reduced the crystallization rate of the samples, and that increasing crystallization temperature decreased the crystallization rate of all the samples. The spherulites of neat PBS and P(BS-b-PEGS) showed banded morphologies. T...

Organo-modified montmorillonites and poly(p-dioxanone) (PPDO) diol prepolymers were used to prepare Poly(p-dioxanone)-PU/organic montmorillonite (PPDO-PU/OMMT) nanocomposites by chain-extending reaction. The crystallization behavior and spherulitic morphology of PPDO-PU/OMMT nanocomposites were investigated by WXRD, differential scanning calorimetry, and polarized optical microscopy. The results show that the regularity of the chain structure plays a dominant role during the crystallization process rather than that of OMMT content and its dispersion status in PPDO matrix. With similar molecular weight and same OMMT content, PPDO-PU/OMMT nanocomposite, which derived from lower molecular weight PPDO prepolymer, exhibits lower crystallization rate, melting point, and crystallinity. The influence of the clay content on the crystallization behavior highly depends on its dispersing state. The nucleating effect of OMMT can be only observed at high loading percentage. For the nanocomposites with low clay loading percentage, the retarding effect of exfoliated platelets on the chain-ordering into crystal lamellae became the key factor. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Biodegradable and biocompatible poly(p-dioxanone)–poly(tetramethylene oxide)glycol (PPDO–PTMEG) multiblock copolymers with excellent shape memory effect and mechanical properties were developed by coupling PPDO-diol and PTMEG-diol with 1,6-hexamethylene diisocyanate (HDI). The influences of chain structure, microphase separating morphology on shape memory effect, and biocompatibility were investigated systematically. The TEM observation of PPDO–PTMEG poly(ether-ester)-polyether exhibited the relationship between characteristic microphase separating morphology and shape memory effect. Interestingly, differential scanning calorimetry (DSC) analysis indicated that Tg,PPDO was close to Tc,PTMEG, which provided the possibility that the reversible phase combined PTMEG segments and the amorphous phase of PPDO segments. The synergistic effect ensured copolymers owning both high Rf and Rr (96.6% and 92.9% with PTMEG segments only 15% in weight fraction), as well as the mechanical properties when T > Ttrans. Moreov...