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Series of Er3+/Yb3+/Fe3+-tridoped NaBiF 4 nanoparticles were synthesized through a simple precipitation reaction method at room temperature. The effect of the Fe3+ ions on the microstructure and upconversion (UC) luminescence properties of the developed samples were studied in detail. Through the Fe3+ ions doping engineering, the enhancement in both green and red UC emission intensities were observed and the optimal doping concentration for Fe3+ ions was revealed to be 30 mol%. Owing to the fluorescence intensity ratio technology, the optical thermometric performances of the resultant products in the temperature range of 303–543 K were investigated and the maximum sensor sensitivity of the studied nanoparticles was 0.0053 K−1 at 543 K. Moreover, the internal heating behaviors of the obtained nanoparticles were investigated and the product temperature was improved to 399 K when the pump power was set at 260 mW. Our systematic and complementary studies suggested that the Er3+/Yb3+/Fe3+-tridoped NaBiF 4 nanoparticles with splendid UC behaviors were poised as next-generation promising candidates for nanothermometer and optical heaters. • The Er3+/Yb3+/Fe3+-tridoped NaBiF 4 nanoparticles were successfully prepared at room temperature. • With introducing of Fe3+, both microstructure and UC emission performance of studied samples were tailored. • The maximum sensor sensitivity of the synthesized nanoparticles as high as 0.0053 K−1 at 543 K. • The prepared nanoparticles can convert the excitation light source into heat. [ABSTRACT FROM AUTHOR]

W/W2C heterostructured nanoparticles encapsulated by N,P dual-doped carbon (W/W2C@NPC) fabricated by the carbonization of in situ polymerized polyaniline (PANI) and phosphotungstic acid require low overpotentials of 55 mV and 82 mV vs. RHE to achieve a cathodic current density of 10 mA cm−2 in acidic and alkaline electrolytes, respectively. [ABSTRACT FROM AUTHOR]

• ZSM-5 zeolite doped with Zn species showed excellent EDC cracking performance. • The acidity of the zeolite catalyst played a decisive role in EDC cracking reaction. • The catalytic performance was investigated by DFT calculations. The acidity and porosity of zeolite catalysts are crucial parameters affecting the catalytic performance. In this work, alkali treatment and metal species loading were used to modify the porosity and acidity of ZSM-5 zeolite to prepare an efficient catalyst for the 1,2-dichloroethane cracking reaction. After optimization, the highly active catalyst Zn (1%) /ZSM-5-120 was obtained, and 78% conversion of EDC and 99% selectivity toward VCM could be achieved under the conditions of 300 °C and 3.0 h−1 (WHSV). A detailed investigation was conducted on the effects of acidity, texture properties and metal species loaded on ZSM-5 zeolite on the 1,2-dichloroethane cracking reaction. Catalytic cracking of 1,2-dichloroethane to produce Vinyl Chloride Monomer using zeolite catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Developing state-of-the-art materials for protecting human from unwanted ionizing radiations is urgent and significant for the rapid development of nuclear facilities. Here, bismuth borate nanoparticles have been fabricated via a facile sol-gel process. Characterization with X-ray diffraction, scanning electron microscopy, and transmission electron microscopy reveals that the product is composed of high-purity orthorhombic Bi 6 B 10 O 24 phase and exhibits a typical single crystal with the size ranging from 100 to 300 nm. The product has an excellent ability to jointly attenuate both neutron and γ-ray. This significant work provides a material with not only good radiation shielding but also other fascinating features, such as environment-friendly. [ABSTRACT FROM AUTHOR]

Multivalent mannose-functionalized nanoparticles self-assembled from amphiphilic β-cyclodextrins (β-CDs) facilitate the targeted delivery of anticancer drugs to specific cancer cells. Doxorubicin (DOX)-loaded nanoparticles equipped with multivalent mannose target units were efficiently taken up via receptor-mediated endocytosis by MDA-MB-231 breast cancer cells that overexpress the mannose receptor. Upon entering the cell, the intracellular pH causes the release of DOX, which triggers apoptosis. Targeting by multivalent mannose significantly improved the capability of DOX-loaded nanoparticles to inhibit the growth of MDA-MB-231 cancer cells with minimal side effects in vivo. This targeted and controlled drug delivery system holds promise as a nanotherapeutic for cancer treatment. [ABSTRACT FROM AUTHOR]

Engineering multifunctional nanocarriers for targeted drug delivery shows promising potentials to revolutionize the cancer chemotherapy. Simple methods to optimize physicochemical characteristics and surface composition of the drug nanocarriers need to be developed in order to tackle major challenges for smooth translation of suitable nanocarriers to clinical applications. Here, rational development and utilization of multifunctional mesoporous silica nanoparticles (MSNPs) for targeting MDA-MB-231 xenograft model breast cancer in vivo are reported. Uniform and redispersible poly(ethylene glycol)-incorporated MSNPs with three different sizes (48, 72, 100 nm) are synthesized. They are then functionalized with amino- β-cyclodextrin bridged by cleavable disulfide bonds, where amino- β-cyclodextrin blocks drugs inside the mesopores. The incorporation of active folate targeting ligand onto 48 nm of multifunctional MSNPs (PEG-MSNPs48-CD-PEG-FA) leads to improved and selective uptake of the nanoparticles into tumor. Targeted drug delivery capability of PEG-MSNPs48-CD-PEG-FA is demonstrated by significant inhibition of the tumor growth in mice treated with doxorubicin-loaded nanoparticles, where doxorubicin is released triggered by intracellular acidic pH and glutathione. Doxorubicin-loaded PEG-MSNPs48-CD-PEG-FA exhibits better in vivo therapeutic efficacy as compared with free doxorubicin and non-targeted nanoparticles. Current study presents successful utilization of multifunctional MSNP-based drug nanocarriers for targeted cancer therapy in vivo. [ABSTRACT FROM AUTHOR]

Highlights: [•] The nanosized pit-like film is formed on aluminum after chemical etch by NaOH solution. [•] High hydrophobic films were prepared by immersed etched aluminum in an ethanol solution containing stearic acid. [•] Aluminum shows a low friction with long wear life by combining chemical etch and stearic acid overcoat. [ABSTRACT FROM AUTHOR]

Abstract: A bifunctional maleimido-tetra(ethylene glycol)-poly(glycerol monoacrylate) (MAL-TEG-PGA) polymer was synthesized and used as a linker to couple functional biomolecules to iron oxide nanoparticles. The cell-penetrating peptide Tat was chosen as a model ligand and successfully conjugated to the surface of Fe3O4 nanoparticles using MAL-TEG-PGA. The Tat-conjugated Fe3O4 nanoparticles can be prepared simply by applying the linker to the iron oxide nanoparticles and then coupling the Tat peptide to the maleimide terminus or by coating the nanoparticles with a pre-coupled linker. Cell-uptake studies demonstrated that the Tat peptide was an efficient functional biomolecule to translocate iron oxide nanoparticles into the cell nucleus. Tat-conjugated nanoparticles thus prepared may be useful for drug or gene delivery. [Copyright &y& Elsevier]

• Pt nanoparticles embedded at the interface between CdS and NaNbO 3. • 18%CdS/2%Pt/N-NaNbO 3 nanorods shows the highest activity of 14,218 μmol⋅ g−1⋅ h−1. • The unique Z-scheme charge transfer mechanism is proposed. • The Pt nanoparticle bridge plays the important role. The development of heterojunction photocatalysts is still limited by poor interfacial charge carriers separation efficiency. In this work, we have successfully designed CdS/Pt/N-NaNbO 3 multilayer bridged nanostructure by embedding of Pt nanoparticles (NPs) into the interface between CdS quantum dots (CdS QDs) and perovskite N-doped NaNbO 3. The Pt NPs not only play the role of bonding CdS QDs and NaNbO 3 , but also provide a motive force for the charge carriers transfer and enormously shorten the migration path. Apart from the efficient Z-scheme charge transmission path of the CdS/Pt/N-NaNbO 3 nanorods, strong visible light absorption (400−800 nm) can also be tailored by N doping and introducing of Pt NPs, CdS QDs, demonstrated by the UV–vis. DRS measurement. As expected, the photocatalytic hydrogen evolution rate of 18 %CdS/2%Pt/N-NaNbO 3 nanorods is 134 and 28 times higher than that of bare NaNbO 3 nanorods and CdS QDs, respectively, under visible light (λ > 420 nm). This is the highest value so far reported among the NaNbO 3 -based photocatalysts. This study has important implications for photocatalytic hydrogen evolution and novel fabrication of NaNbO 3 -based materials. [ABSTRACT FROM AUTHOR]

Bacterial biofilms pose a serious threat to human health, as they prevent the penetration of antimicrobial agents. Developing nanocarriers that can simultaneously permeate biofilms and deliver antibacterial agents is an attractive means of treating bacterial biofilm infections. Herein, photosensitive metal–organic framework (MOF) nanoparticles were developed to promote the penetration of antibiotics into biofilms, thereby achieving the goal of eradicating bacterial biofilms through synergistic photodynamic and antibiotic therapy. First, a ligand containing benzoselenadiazole was synthesized and incorporated into MOF skeletons to construct benzoselenadiazole-doped MOFs (Se-MOFs). The growth of the Se-MOFs could be regulated to obtain nanoparticles (Se-NPs) in the presence of benzoic acid. The singlet oxygen (1O2) generation efficiencies of the Se-MOFs and Se-NPs were evaluated. The results show that the Se-NPs exhibited a higher 1O2 generation efficacy than the Se-MOF under visible-light irradiation because the small size of the Se-NPs was conducive to the diffusion of 1O2. Afterward, an antibiotic drug, polymyxin B (PMB), was conjugated onto the surface of the Se-NPs via amidation to yield PMB-modified Se-NPs (PMB-Se-NPs). PMB-Se-NPs exhibit a synergistic antibacterial effect by specifically targeting the lipopolysaccharides present in the outer membranes of Gram-negative bacteria through surface-modified PMB. Benefiting from the synergistic therapeutic effects of antibiotic and photodynamic therapy, PMB-Se-NPs can efficiently eradicate bacterial biofilms at relatively low antibiotic doses and light intensities, providing a promising nanocomposite for combating biofilm infections. [ABSTRACT FROM AUTHOR]

Low durability and fuel cell performance block the widespread application of polymer electrolyte fuel cells (PEFCs). Here, we deposit platinum nanoparticles on carbon nanotubes (CNTs) before coating by end-capped hyperbranched sulfonated macromolecules (E-HBM), which could provide sufficient proton conductivity in catalyst layer thanks to the presence of −SO3H groups. The fabricated electrocatalyst loses 43 % of initial electrochemical surface area (ECSA) after 200 000 potential cycles from 1.0 V to 1.5 V vs. RHE, which is 3 and 20 times higher than that of noncoated and commercial electrocatalysts, respectively. The mass and specific activities of newly fabricated electrocatalyst measured before and after durability test are 1.4 times higher than that of commercial carbon black/Pt. Nafion ionomer-free membrane electrode assembly is fabricated from the newly designed electrocatalyst, and its fuel-cell performance reaches 668 mW cm−2 with Pt loading of 0.1 mg cm−2, which is twice higher than that of commercial CB/Pt thanks to the homogeneous conductive macromolecules (E-HBM) layers on CNTs acting as ionomer and facilitating the proton delivery in the catalyst layer. [ABSTRACT FROM AUTHOR]

Here, we report a facile method to synthesize ruthenium phosphides with diameter 1 nm and an amorphous structure at room temperature. Only 31 mV vs. RHE overpotential is required to deliver 10 mA cm−2 and no degradation in hydrogen evolution reaction (HER) performance is recorded after 24 h of catalysis at 100 mA cm−2. [ABSTRACT FROM AUTHOR]

A series of thirty one melampomagnolide B-triazole conjugates was synthesized via Copper(I) oxide nanoparticles catalyzed click chemistry. These conjugates were evaluated for their anti-cancer activities against a panel of five human cancer cell lines. The most active compound 6e showed high activity against HCT116 cell line with IC 50 value of 0.43 μM, which demonstrated 11.5-fold improvement compared to that of the parent compound melampomagnolide B (IC 50  = 4.93 μM). Compound 6e showed significant efficacy of inducing apoptosis, inhibiting proliferation and migration of HCT116 cells. The preliminary molecular mechanism of 6e was also investigated. On the base of these results, compound 6e might be considered as a promising candidate for further evaluation as a potential anti-cancer drug. [ABSTRACT FROM AUTHOR]

Precise control over the configuration, size and density of Au nanoparticles (NPs) has offered an efficient route to enhance and optimize the performance and usability of various NP-based applications. In this study we successfully demonstrate precise control of the configuration, size and density of self-assembled Au nanostructures on 4H-SiC (0001) via systematic variation of the deposition amount, annealing temperature and duration. Depending on the deposition amount at a fixed annealing temperature and duration, the self-assembled Au NPs are successfully fabricated based on the Volmer–Weber growth model, and the NPs nucleate as round dome shapes and evolve into hexagonal nano-crystals with facet formation along with the increased deposition amounts. For the variation of annealing temperature, the Au nanostructures radically develop into two distinct regimes: i.e. irregular Au nano-mounds (regime I) between 400 and 700 °C based on the diffusion limited agglomeration (DLA) model and round dome-shaped droplets (DPs) (regime II) between 750 and 1000 °C. The dwelling time, size and density evolution of the round dome-shaped Au DPs are discussed based on the Ostwald ripening theory. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel amino-functionalized ZIF-8 (ZIF-8-NH 2) nanoparticles were prepared and incorporated in polymeric (PVA) matrix. • The synthesized ZIF-8-NH 2 exhibits uniform morphology, smaller size, controllable pore size, enhanced hydrophilicity, and beneficial amino groups. • Mixed Matrix Membranes (MMMs) embedded with ZIF-8-NH 2 nanoparticles show better compatibility and excellent separation performance. • 7-ZIF-8-NH 2 /PVA MMM displays high separation factor and a comparable total flux. • Long-term stable operation of the ZIF-8-NH 2 /PVA MMMs have obvious production benefits in practical applications. The incorporation of attainable amine functionality in zeolitic imidazolate framework-8 (ZIF-8) is utilized to enhance the pervaporation performance for ethanol/ water separation applications. Using 2-aminobenzimidazole, a ligand with NH 2 -functionalized group, displacement of the ZIF-8 original ligand during de novo synthesis while preserving the ZIF-8 initial structure, which produces a novel mixed- linker ZIF material (ZIF-8-NH 2) with smaller nanocrystal size, controllable pore size, and enhanced hydrophilicity. A series of different mixed matrix membranes (MMMs) were fabricated by incorporating ZIF-8-NH 2 into poly(vinyl alcohol) (PVA) matrix. Various characterization techniques, such as FTIR, 1H NMR, XRD, SEM, TGA, and Contact angle etc. were employed to demonstrate the properties of prepared ZIF nanoparticles and the MMMs. The results indicated that ZIF-8-NH 2 and the MMMs were perfectly fabricated, which were attributed to better dispersion and compatibility between them. In particular, 7-ZIF-8-NH 2 /PVA MMM exhibited a comparable total flux of 142 g/m2·h and water/ethanol separation factor of 925, which were increased by 73 and 524%, on the basis of the pristine PVA membrane. In addition, different nanofillers, APTES crosslinking, ZIF-8-NH 2 loading, operating temperature, feed concentration, and membrane stability were evaluated in detail. This study might provide a promising prospect for designing MOF-based MMMs with the introduction of various functional groups. [ABSTRACT FROM AUTHOR]

Abstract: Triazole moiety is frequently employed in drug discovery and optimization. However, most syntheses of triazole drugs involve isolation of highly explosive azides. Herein we report safe and high efficient syntheses of triazole drugs in aqueous/organic solvent systems with Cu2O nanoparticle (Cu2O-NP) as the catalyst of azide–alkyne cycloaddition (CuAAC). Since Cu2O-NP can be efficiently dispensed in aqueous and some organic solvents, the azide solutions from the previous preparation could be used directly in the next CuAAC stage without isolation. Therefore, this synthetic strategy is safe, convenient, and high yielding for the syntheses of triazole drugs. [Copyright &y& Elsevier]

Photodynamic therapy (PDT) is an emerging cancer treatment combining light, oxygen, and a photosensitizer (PS) to produce highly cytotoxic reactive oxygen species that cause cancer cell death. However, most PSs are hydrophobic molecules that have poor water solubility and cannot target tumor tissues, causing damage to normal tissues and cells during PDT. Thus, there is a substantial demand for the development of nanocarrier systems to achieve targeted delivery of PSs into tumor tissues and cells. This review summarizes the research progress in PS delivery systems for PDT treatment of tumors and focuses on the recent design and development of multifunctional nanoparticles as PS delivery carriers for enhanced PDT. These multifunctional nanoparticles possess unique properties, including tunable particle size, changeable shape, stimuli-responsive PS activation, controlled PS release, and hierarchical targeting capability. These properties can increase tumor accumulation, penetration, and cellular internalization of nanoparticles to achieve PS activation and/or release in cancer cells for enhanced PDT. Finally, recent developments in multifunctional nanoparticles for tumor-targeted PS delivery and their future prospects in PDT are discussed. [ABSTRACT FROM AUTHOR]