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The pressing demand for innovative approaches to create delivery systems with heightened drug loading and prolonged circulation has spurred numerous efforts, yielding some successes but accompanied by constraints. Our study proposes employing dendritic lipopeptide with precisely balanced opposing charges to extend blood residency for biomimetic nanoplatforms. Neutrally mixed-charged zwitterionic nanoparticles (NNPs) achieved a notable 19 % simvastatin loading content and kept stable even after one-month storage at 4 °C. These nanoplatforms demonstrated low cytotoxicity in NIH-3T3 and L02 cells and negligible hemolysis (<5 %). NNPs inhibited protein adhesion (>95 %) from positively and negatively charged sources through surface hydration. In comparison to positively charged CNPs, NNPs demonstrated an 86 % decrease in phagocytic rate by BMDMs, highlighting their efficacy. Importantly, NNPs showed prolonged circulation compared to CNPs and free simvastatin. These findings highlight the potential of this biomimetic nanoplatform for future therapeutic applications with enhanced drug loading and circulation traits., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Hypothesis: Encapsulation of sensitive water-soluble bioactive materials such as fragrances, polyphenols and enzymes poses an immense challenge with capsules templated from water-in-oil (w/o) emulsions. Generation of radicals, heating, and extreme pH that are necessary for shell formation through interfacial reactions may have undesired influences on the active ingredients and thus lower their activity., Experiments: To overcome these limitations, we present a method to encapsulate sensitive ingredients, whereby capsules are templated from a w/o Pickering emulsion stabilized by binary particles of different hydrophilicity levels; the particles assembled at the water/oil interface are then crosslinked by polydiisocyanate (PHDI) at room temperature and neutral pH. Zein and casein nanoparticles were used as hydrophilic stabilizers and lipase was chosen as a model sensitive biomolecule that was encapsulated in the water core., Findings: Our results indicated that the enzymes encapsulated in colloid capsules had higher activity than those encapsulated in traditional w/o Pickering emulsion without shell crosslinking. The capsule structure effectively protected enzymes from the outer environment. This method is well suited for the encapsulation and protection of sensitive ingredients and shows great application in food, drug, and cosmetic industries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Hypothesis: Although it is well-accepted that iron oxide nanoparticles are considered as artificial enzymes when their surface is hydrophilic, the enzyme-like properties of iron oxide nanoparticles with hydrophobic surface coating is unexplored. This work demonstrates that hydrophobic iron oxide nanocrystals coated with a layer of oleic acid could serve as artificial enzymes when their surface is covered by a layer of ionic surfactant. Furthermore, the co-assembly of iron oxide nanocrystals and porous organic cages could modulate their enzyme-like activities., Experiments: Co-assembly of iron oxide (Fe 3 O 4 ) nanocrystals with different size and porous organic cages (POCs) was performed by an emulsion-confined strategy to achieve hybridized Fe 3 O 4 /POCs co-assemblies. The peroxidase-mimic activity of these co-assemblies were assessed in the presence of 3, 3', 5, 5'-Tetramethylbenzidine (TMB) and hydrogen peroxide. Finally, these co-assemblies were applied as sensors to detect glucose and hydrogen peroxide., Findings: Co-assembly of Fe 3 O 4 nanocrystals and POCs resulted in the self-assembly of Fe 3 O 4 nanoparticles into two-dimensional nanoparticle superlattices on the eight (111) facets of the octahedral POCs colloidal crystals. The unique oil-in-water (O/W) emulsion confined assembly method switches the Fe 3 O 4 nanoparticles and POC crystals from hydrophobic to hydrophilic because of the strong hydrophobic interactions. Importantly, these co-assemblies dispersed in water showed strong peroxidase-mimic activity in water despite that their surface is covered by a bilayer of aliphatic chains. Furthermore, the intrinsic enzymatic activity of the co-assemblies is highly dependent on the size of the nanocrystals, and a higher catalytic activity is achieved from a larger sized Fe 3 O 4 nanocrystal., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Biology exploits a transcription-translation approach to deliver structural information from DNA to the protein-building machines with high precision. Here, we show how the structural information of small synthetic molecules could be used to guide the assembly of inorganic nanoparticles into diversified yet long-range ordered superstructures, enabling the information transfer across four or five orders of magnitude in length scale. We designed three perylene diimide (PDI) based isomers differing by their site-specific substitutions of the methyl group, which were able to supramolecularly polymerize into diverse structures. Importantly, coassembly of these PDI isomers with nanoparticles (NPs) could produce diverse long-range ordered nanoparticle superstructures, including one-dimensional NPs chains, double helical NPs assemblies and two-dimensional NPs superlattices. Equally important, we demonstrate that the information originated from small molecules could diversify the functions of the self-assembled nanocomposites., (© 2022 Wiley-VCH GmbH.)

Folding of two-dimensional nanoparticle superlattices is achieved through templated assembly on as-formed supramolecular nanosheets, which undergo a folding process within the emulsion droplets during the evaporation of the inner phase liquid. Building the folded nanoparticle superlattices opens a new gateway to reshape the properties of inorganic solids.

In this study, Pickering emulsion gels were prepared by the self-gel method based on kappa carrageenan (kC). The effects of particle stabilizers and polysaccharide concentrations on the microstructure, rheological characteristics, and texture of Pickering emulsion gels stabilized by xanthan gum/lysozyme nanoparticles (XG/Ly NPs) with kC were discussed. The viscoelasticity of Pickering emulsion gels increased significantly with the increase of kC and XG/Ly NPs. The results of temperature sweep showed that the gel formation mainly depended on the kC addition. The XG/Ly NPs addition could accelerate the formation of Pickering emulsion gels and increase its melting temperature (Tmelt), which is helpful to improve the thermal stability of emulsion gels. Cryo-scanning electron microscope (Cryo-SEM) images revealed that Pickering emulsion gel has a porous network structure, and the oil droplets were well wrapped in the pores. The hardness increased significantly with the increase of XG/Ly NPs and kC. In particular, the Pickering emulsion gel hardness was up to 2.9 Newton (N) when the concentration of kC and XG/Ly NPs were 2%. The results showed that self-gelling polysaccharides, such as kC, could construct and regulate the structure and characteristics of Pickering emulsion gel. This study provides theoretical support for potential new applications of emulsion gels as functional colloids and delivery systems in the food industry. [ABSTRACT FROM AUTHOR]

Here, we show that aqueous dispersions of inorganic nanoparticles bearing negative surface charges would trigger the chiral assembly of organic radical cations solubilized in organic solvent at the liquid–liquid interface, which consequently produces stable droplets covered by a layer of inorganic/organic chiral nanocomposites. We demonstrate that chirality transfer across the liquid–liquid interface from the chiral organic monomers to the nanoparticle assemblies is realized. Surprisingly, opposite handedness between molecular assemblies and nanoparticle assemblies is determined from both CD and CPL measurements. Moreover, the functionalities of these "chiral" droplets could be further engineered through either a simple mixing or a droplet merging strategy, which enables to produce fluorescent emissive‐tunable, magnetic, as well as magnetofluorescent dual‐functional droplets. [ABSTRACT FROM AUTHOR]

Nanoscale curvature‐dependent interactions are of paramount importance in biological systems. Here, we report that nanoscale curvature plays an important role in regulating the chirality of self‐assembled nanocomposites from chiral organic molecules and achiral nanoparticles. Specifically, we show that the supramolecular chirality of the nanocomposites markedly depends on the nanoparticle curvature, where small‐sized nanoparticles of high curvature and large‐sized nanoparticles of low curvature lead to nanocomposites with opposite chirality. Quantitative kinetic experiments and molecular dynamics simulations reveal that nanoparticle curvature plays a key role in promoting the pre‐nucleation oligomerization of chiral molecules, which consequently regulates the supramolecular chirality of the nanocomposites. We anticipate that this study will aid in rational design of an artificial cooperative system giving rise to emergent assembling phenomena that can be surprisingly rich and often cannot be understood by studying the conventional noncooperative systems. [ABSTRACT FROM AUTHOR]

The pressing demand for innovative approaches to create delivery systems with heightened drug loading and prolonged circulation has spurred numerous efforts, yielding some successes but accompanied by constraints. Our study proposes employing dendritic lipopeptide with precisely balanced opposing charges to extend blood residency for biomimetic nanoplatforms. Neutrally mixed-charged zwitterionic nanoparticles (NNPs) achieved a notable 19 % simvastatin loading content and kept stable even after one-month storage at 4 °C. These nanoplatforms demonstrated low cytotoxicity in NIH-3T3 and L02 cells and negligible hemolysis (<5 %). NNPs inhibited protein adhesion (>95 %) from positively and negatively charged sources through surface hydration. In comparison to positively charged CNPs, NNPs demonstrated an 86 % decrease in phagocytic rate by BMDMs, highlighting their efficacy. Importantly, NNPs showed prolonged circulation compared to CNPs and free simvastatin. These findings highlight the potential of this biomimetic nanoplatform for future therapeutic applications with enhanced drug loading and circulation traits. Addressing the demand for advanced drug delivery systems with heightened loading and prolonged circulation, we propose a strategy employing precisely balanced dendritic lipopeptide charges for biomimetic nanoplatforms. These systems efficiently encapsulate hydrophobic drugs with high drug loading capacity (up to 19 %), yielding zwitterionic-like surfaces without additional modifications. The resulting biomimetic zwitterionic nanoparticles demonstrate robust immune evasion and extended bloodstream residence. [Display omitted] • Fine-tuning biomimetic nanoparticle surfaces with balanced dendritic lipopeptide charges. • Biomimetic zwitterionic nanoparticles: efficient encapsulation, high loading, and stability • The zwitterionic nanoparticles evade immune responses, extending bloodstream presence. [ABSTRACT FROM AUTHOR]

Catalytically active bimetallic nanoparticles are at the forefront of catalytic materials research. In this work, bimetallic alloy nanoparticles are synthesized by diffusion and reduction of two kinds of metal ions within cyclodextrin metal organic frameworks (CD-MOFs). Thanks to the spatial confinement of the microporous structure of CD-MOF crystals, bimetallic nanoparticles with uniform sizes are produced. The as-synthesized bimetallic nanoparticles can be freely released into water because these CD-MOFs can be easily dissolved in water. Therefore, these bimetallic nanoparticles free of surface coatings are highly solution processable and can be loaded onto other catalytic supports dispersed in water (i.e., oxides, carbons and other MOFs). The obtained composite catalysts are evaluated by both the CO oxidation reaction and 4-nitrophenol reduction. Overall, the newly developed catalytic system exhibits excellent catalytic activity, durability and recyclability. [ABSTRACT FROM AUTHOR]

Abstract: The encapsulated Au/CeO2 hollow composite shows the effects of different pretreatment conditions on CO oxidation, showing complete conversion temperatures for CO in the order O2 pretreatment (T100=74 °C)>N2 pretreatment (T100=142 °C)>CO pretreatment (T100=167 °C). Because of the good confinement provided by the uniform pores of as‐prepared CeO2, the size of deposited Au nanoparticles embedded in the pores of CeO2 can be well controlled. Pretreated Au/CeO2 catalysts have a good stability with no clear deactivation even after 70 h. A systematic characterization was performed by employing various techniques (XRD, H2 temperature‐programmed reduction, scanning transmission electron microscopy with energy‐dispersive spectroscopy, Raman spectroscopy, X‐ray photoelectron spectroscopy, and in situ diffuse reflectance infrared Fourier transform spectroscopy) to understand the importance of the Au–CeO2 interaction. This revealed that the O2 pretreatment may result in (a) the migration of lattice oxygen atoms to the surface region and clearly increased number of oxygen vacancies in CeO2; (b) the increase of Au−Ox and Au−Ox−Ce bond lengths; (c) the creation of electron holes in the CeO2 substrate and electron deficiencies in Au nanoparticles as well as a strong Au–CeO2 interaction; and (d) increased number of bicarbonates on the surface and Auδ+−CO bonds were produced during CO oxidation. All these features are responsible for an overall enhanced activity of CO oxidation and high durability of the Au/CeO2 hollow composite. [ABSTRACT FROM AUTHOR]

Ceria nanoparticles with 4 and 7 atom-% manganese dopant were synthesized through a template-free solvothermal method. The structure of the samples was characterized by powder X-ray diffraction (XRD). Monodispersed nanospheres of average size 130 nm were observed in transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), and field-emission scanning electron microscopy (FE-SEM) analyses. Manganese ions were introduced into the system and it is confirmed that the Mn species dissolve within the CeO2 lattice by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Furthermore, the as-obtained Mn-doped ceria nanoparticles revealed superior catalytic performance in CO oxidation in contrast with pure CeO2 prepared by the same route. [ABSTRACT FROM AUTHOR]

Abstract: Monodisperse CeO2 hollow nanoparticles were synthesized by a template-free hydrothermal method. The average size of the nanoparticles was measured to be 75nm. Detailed experiments revealed that the CeO2 hollow nanoparticles were formed directly by oriented attachment of the initial CeO2 nanocrystals. Although Cu2+ was introduced into the system, the final CeO2 product was free of Cu species, which was confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectrum (XPS) studies. Furthermore, the as-prepared CeO2 hollow nanoparticles revealed superior catalytic activity toward CO oxidation compared to commercial CeO2 fine powders. It may provide a new path for the fabrication of inorganic hollow structures upon introducing alien metal ions. [Copyright &y& Elsevier]

The ability to control the assembly of micro/nanosized particles at liquid-liquid interface with external inputs promises new opportunities in nanofabrication and biomedicines. This work aims to demonstrate a way to control of dynamic assembly of nanoparticles at liquid-liquid interface by light and magnetic field, which consequently enables the formation of dynamic emulsion droplets. Magnetic Fe 3 O 4 nanoparticles functionalized with azobenzene moieties (Fe 3 O 4 @AZO) were synthesized and were dispersed in toluene/(N, N -dimethylformamide, DMF) binary solvent. After irradiation with UV or visible light, the assembly behavior of these Fe 3 O 4 nanoparticles were evaluated by electron microscopy and fluorescent microscopy. Under UV light, Fe 3 O 4 @AZO nanoparticles were self-assembled due to the increase of dipolar interaction from the photoisomerization of azobenzene and polar molecules, DMF, were harvested from a binary solvent of DMF/toluene. While under visible light, a relief of dipolar interactions between Fe 3 O 4 @AZO nanoparticles can induce the secondary assembly of these Fe 3 O 4 @AZO nanoparticles at DMF-toluene interface, resulting in DMF droplets covered by a layer of nanoparticle superlattices. More importantly, coupled with a magnetic field, these emulsion droplets can be shaped into one dimensional ones during the interfacial assembly process, thereby giving rise to dynamic emulsions controlled by light and magnetic field. [ABSTRACT FROM AUTHOR]

In this study, magnetic zirconium-iron oxide nanoparticles (MZION) of different Fe/Zr molar ratios were successfully prepared using the co-precipitation method, and their performance for phosphate removal was systematically evaluated. The as-obtained adsorbents were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Zeta potential analyzer, Fourier transform infrared spectroscopy (FT-IR) and Brunauer Emmett Teller (BET) specific surface area analysis. The effects of pH, ionic strength, and co-existing ions (including Cl − , SO 4 2− , NO 3 − and HCO 3 − ) were measured to evaluate the adsorption performance in batch experiments. The results showed that decreasing the Fe/Zr molar ratios increased the specific surface area that was propitious to adsorption process, but the adsorption capacity enhanced with the decrease of Fe/Zr molar ratios. Phosphate adsorption on MZION could be well described by the Freundlich equilibrium model and pseudo-second-order kinetics. The adsorption of phosphate was highly pH dependent and decreased with increasing pH from 1.5 to 10.0. The adsorption was slightly affected by ionic strength. With the exception of HCO 3 − , co-existing anions showed minimum or no effect on their adsorption performance. After adsorption, phosphate on these MZION could be easily desorbed by 0.1 M NaOH solution. The phosphate adsorption mechanism of MZION followed the inner-sphere complexing mechanism, and the surface OH groups played a significant role in the phosphate adsorption. Additionally, the main advantages of MZION consisted in its separation convenience and highly adsorption capacity compared to other adsorbents. [ABSTRACT FROM AUTHOR]