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Three new and different homo- and hetero-bimetallic polyoxometalate (POM) species have been synthesised by simple one-pot synthetic methods utilising naturally occurring bismite (Bi 2 O 3 ) (or Bi(NO 3 ) 3 ·5H 2 O) and aryl sulfonic acids. The POM species isolated are (NH 4 ) 14 [Bi 2 W 22 O 76 ]·14H 2 O (1·14H 2 O), (NH 4 )[Bi(DMSO) 7 ][Mo 8 O 26 ]·H 2 O (2·H 2 O) and [(NH 4 ) 4 (Mo 36 O 108 (OH) 4 ·16H 2 O)]·45H 2 O (3·45H 2 O). The compounds have been characterised by X-ray crystallography, energy dispersive X-ray spectroscopy (EDX), powdered X-ray diffraction (PXRD), mass spectrometry (ESI-MS), Raman spectroscopy, thermogravimetric (TGA) and ICP analyis. In vitro cytoxicity and proliferation studies conducted on 1 and 3, highlight the low toxicity of these species.

Bioinspired complexes employing the ligands 6-tert-butylpyridazine-3-thione (SPn) and pyridine-2-thione (SPy) were synthesized and fully characterized to mimic the tungstoenzyme acetylene hydratase (AH). The complexes [W(CO)(C 2 H 2 )(CHCH-SPy)(SPy)] (4) and [W(CO)(C 2 H 2 )(CHCH-SPn)(SPn)] (5) were formed by intramolecular nucleophilic attack of the nitrogen donors of the ligand on the coordinated C 2 H 2 molecule. Labelling experiments using C 2 D 2 with the SPy system revealed the insertion reaction proceeding via a bis-acetylene intermediate. The starting complex [W(CO)(C 2 H 2 )(SPy) 2 ] (6) for these studies was accessed by the new acetylene precursor mixture [W(CO)(C 2 H 2 ) n (MeCN) 3-n Br 2 ] (n=1 and 2; 7). All complexes represent rare examples in the field of W-C 2 H 2 chemistry with 4 and 5 being the first of their kind. In the ongoing debate on the enzymatic mechanism, the findings support activation of acetylene by the tungsten center., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Incorporation of monatomic 2p ligands into the core of iron-sulfur clusters has been researched since the discovery of interstitial carbide in the FeMo cofactor of Mo-dependent nitrogenase, but has proven to be a synthetic challenge. Herein, two distinct synthetic pathways are rationalized to install nitride ligands into targeted positions of W-Fe-S clusters, generating unprecedented nitride-ligated iron-sulfur clusters, namely [(Tp*) 2 W 2 Fe 6 (μ 4 -N) 2 S 6 L 4 ] 2- (Tp*=tris(3,5-dimethyl-1-pyrazolyl)hydroborate(1-), L=Cl - or Br - ). 57 Fe Mössbauer study discloses metal oxidation states of W IV 2 Fe II 4 Fe III 2 with localized electron distribution, which is analogous to the mid-valent iron centres of FeMo cofactor at resting state. Good agreement of Mössbauer data with the empirical linear relationship for Fe-S clusters indicates similar ligand behaviour of nitride and sulfide in such clusters, providing useful reference for reduced nitrogen in a nitrogenase-like environment., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Two-dimensional WO 3 nanosheets were prepared by ultrasonic exfoliation of bulk WO 3 ·2H 2 O in water and characterized by transmission electron microscopy, atomic force microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman, dynamic light scattering. The nanosheets were discovered to possess the peroxidase-like catalytic activity, which can catalyze the oxidation of 3, 3', 5, 5'-tetramethylbenzidine by H 2 O 2 . The catalytic mechanism was also investigated by the scavenger experiments. Taking advantage of the peroxidase-like activity of WO 3 nanosheets, a facile colorimetric method for xanthine was developed by combining the oxidation reaction of xanthine catalyzed by xanthine oxidase. The linear range for xanthine was ranged from 25 to 200 μmol L -1 . The limit of detection for xanthine was 1.24 μmol L -1 . The colorimetric method was applied to determine xanthine in urine samples., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Multifunctional nanoplatforms with flexible architectures and tumor microenvironment response are highly anticipated within the field of thermoradiotherapy. Herein, the multifunctional nanoplatforms for thermoradiotherapy have been successfully constructed by the embedding of tungsten disulfide quantum dots (WS 2 QDs) into mesoporous polydopamine nanosponges (MPDA NSs), followed by integration with manganese dioxide (MnO 2 ). MPDA-WS 2 @MnO 2 , the resultant nanoplatforms, exhibit radiosensitization enhanced behavior and a capacity for responsive oxygen self-supplementation. The ingenious mesoporous structure of MPDA NSs serves as reservoir for the assembly of WS 2 QDs to form MPDA-WS 2 nanoparticles (NPs), in which WS 2 QDs provide the radiation enhancement effect, whereas the MPDA NSs framework endows the MPDA-WS 2 @MnO 2 with an excellent photothermal capability. Additionally, the integration of the MnO 2 component works to decompose the tumor-overexpressed H 2 O 2 and alleviate tumor hypoxia subsequently, which has been demonstrated to enhance radiotherapy performance considerably. Meanwhile, the prepared MPDA-WS 2 @MnO 2 nanoplatforms have been evaluated as trimodality contrast agents for computed tomography (CT), multispectral optoacoustic tomography (MSOT), and tumor microenvironment-responsive T 1 -weighted magnetic resonance (MR) imaging that have the potential for real-time guidance and monitoring during cancer therapy. More importantly, when subjected to near infrared (NIR) laser irradiation and X-ray exposure, the tumor is found to be inhibited significantly through the process of combined thermoradiotherapy. The design concepts of embedding WS 2 QDs into MPDA NSs and oxygen self-supplementing hold great potential for multimodal imaging-guided thermoradiotherapy of hypoxic cancer., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A traditional CuWO 4 semiconductor (E g = 2.25 eV) shows photoabsorption in the visible range with an edge at ∼550 nm, limiting its application in near-infrared (NIR) laser-induced photothermal ablation therapy (PAT). To tune the NIR photoabsorption of CuWO 4 , we report a trisodium citrate-induced strategy for generating oxygen vacancies. CuWO 4 and CuWO 4-x nanoparticles are prepared by a facile coprecipitation-solvothermal method in the absence or presence of trisodium citrate (0.2-0.5 g) as the reducing agent. Without trisodium citrate, CuWO 4 consists of aggregated particles, and its dispersion has a typical yellow-green color without NIR photoabsorption. With the addition of trisodium citrate from 0.2 to 0.5 g, CuWO 4-x samples are composed of monodisperse nanodots with increased sizes from ∼2 to ∼6 nm, and the color of these dispersions becomes darker with increased NIR photoabsorption, that is, from 0.178 to 0.685 at 808 nm. As a result, the aqueous dispersion of CuWO 4-x -0.5 nanodots prepared with 0.5 g trisodium citrate exhibits a high photothermal efficiency of 47.6% under 808 nm laser irradiation. Simultaneously, CuWO 4-x -0.5 nanodots have high X-ray attenuation as a CT imaging agent due to the presence of a heavy metal element (W). When the CuWO 4-x -0.5 dispersion is injected into the tumors of mice, the tumors can be observed by CT and thermal imaging. After 808 nm laser irradiation (1.0 W cm -2 , 10 min), cancer cells in vivo can be efficiently ablated by the photothermal effects of CuWO 4-x , without obvious toxicity and side effects. Therefore, CuWO 4-x can act as a novel all-in-one agent for CT imaging-guided photothermal therapy of tumors.

We report a new type of potentiometric pH sensor with sensitivity exceeding the theoretical Nernstian behavior (-59.1 mV/pH). For the pH-sensitive electrode, 1D tungsten oxide (WO 3 ) nanofibers (NFs) were prepared to obtain large surface area and high porosity. These NFs were then stabilized in a reactive porous chloromethylated triptycene poly(ether sulfone) (Cl-TPES) binder, to facilitate proton diffusion into the polymer membrane. The measurements were performed with a differential amplifier using matched MOSFETs and providing a 10-fold amplified signal over a simple potentiometric determination. A high pH sensitivity of -377.5 mV/pH and a linearity of 0.9847 were achieved over the pH range of 6.90-8.94. Improved signal-to-noise ratios with large EMF signal changes of 175 mV were obtained in artificial seawater ranging pH 8.07-7.64 (ΔpH = 0.43), which demonstrates a practical application for pH monitoring in ocean environments.

Here, Au x Rh 1- x alloy nanocrystals (NCs) were used to decorate W 18 O 49 for enhanced detection of n -butanol vapor. Monodisperse Au x Rh 1- x alloy NCs with a tunable composition and urchinlike W 18 O 49 were synthesized by a simple solvothermal method. Au x Rh 1- x alloy NCs were loaded onto the W 18 O 49 surface by the impregnation method. A series of material characterization methods were employed to characterize the structure and morphology of as-synthesized materials. The performance of Au x Rh 1- x -W 18 O 49 -based sensors to n -butanol was investigated. The results demonstrated that the Au 39 Rh 61 -W 18 O 49 -based sensor had the highest response, short response time, good selectivity, excellent repeatability, and stability to n -butanol. The gas sensing mechanism was supposed, the excellent catalytic capability of the Au x Rh 1- x alloy NCs were believed to be a major factor in enhancing the detection of n -butanol.

Nanoconstructions composed of lipid vesicles and inorganic units (nanoparticles, metal complexes) arouse much interest across materials science and nanotechnology as hybrid materials combining useful functionalities from both parts. Ideally, these units are to be embedded into the bilayer to keep the biophysical performance of lipid vesicles having inorganic moieties screened from the environment. This can be achieved by doping a lipid bilayer with cluster complexes of transition metals. In this work, we report the preparation of nanoparticles from trinuclear W 3 S 4 cluster complexes and egg phosphatidylcholine. A systematic study of their properties was performed by the differential scanning calorimetry, NMR spectroscopy, dynamic light scattering, and transmission electron microscopy. Phospholipids and clusters have been found to spontaneously self-assemble into novel cluster-lipid hybrid materials. The behavior of clusters in the hydrophobic lipid environment is determined by the structure of the ligands and cluster-to-lipid ratio. Intact cluster complexes bearing compact hydrophobic ligands are embedded into the hydrophobic midplane of a lipid bilayer, whereas cluster complexes bearing larger ligands drive the aggregation of lipids and cluster complexes. Considering these differences, it could be possible to obtain different self-assembled associates such as cluster-doped liposomes or lipid-covered crystals. These cluster-lipid hybrids can be a platform for the design of new materials for nanotechnology.

Herein, we report the anionic surfactant, ethylene diamine tetraacetic acid (EDTA), mediated synthesis of WO 3 nanoparticles and its subsequent modification through gamma irradiation (GI) and electrochemical immobilization with nicotinamide adenine dinucleotide (NAD). Glassy carbon electrode (GCE) modified with GI-WO 3 NPs and the enzyme NAD exhibited strong electro-oxidation of three important biomolecules such as norepinephrine (NEP), melatonin (MEL) and nicotine (NIC) in 0.1 M phosphate buffer saline (PBS) at physiological pH of 7. Square wave voltammetry (SWV) studies exhibited three well-defined peaks at potentials of 120, 570 and 840 mV, corresponding to the oxidation of NEP, MEL and NIC respectively, indicating that simultaneous determination of these compounds is feasible at the NAD/GI EDTA-WO 3 /GCE. The proposed sensor displayed a wide linear range of 0.010-1000 μM with the lowest detection limit of 1.4 nM for NEP, 2.6 nM for MEL and 1.7 nM for NIC respectively. Furthermore, the modified electrode was successfully applied to detect NEP, MEL and NIC in pharmaceutical and cigarette samples with excellent selectivity and reproducibility., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Oxygen vacancy (OV) tuning was introduced into oxygen-deficient WO3 nanosheets to optimize the chemical and electronic properties. Enhanced electronic conduction, extended light absorption, enhanced HER reaction kinetics and benign photothermal performance were verified by density functional theory (DFT) calculations and experimental studies. Vis-NIR light-enhanced electrocatalytic HER was accomplished with a small overpotential of 52 mV (at 10 mA cm-2) and a low Tafel slope of 37 mV dec-1 and performed much more efficiently than that in darkness, comparable to the noble-metal catalysts (Pt, Pt/C). Moreover, the resultant WO3-OVs possess good photothermal conversion efficiency. The promising potential of the WO3-OVs for anticancer photothermal therapy has been demonstrated with a high photothermal conversion efficiency (∼41.6%) upon single wavelength near-infrared irradiation and an efficient tumor inhibition rate (∼96.8%). This design of photoelectronic/thermal materials paves an exciting new avenue for the conversion of well-developed metal oxides to be high-performance and multifunctional materials for energy and oncology applications.

Density functional theory modelling has been used to design Mo and W-based catalysts MoIII(tBu)(CO) and WIII(tBu)(CO) for CO2 hydrogenation and HCOOH dehydrogenation, which are bio-mimics of the active site of formate dehydrogenase. Based on DFT calculations, the molybdenum and tungsten based complexes are good catalysts in the +3 oxidation state for CO2 hydrogenation with free energies of 24.03 and 21.31 kcal mol-1, respectively. Such a low barrier indicates that our newly designed Mo and W-based complexes are very efficient for CO2 hydrogenation or HCOOH dehydrogenation catalysis. Overall, our computational results provide in depth insights that can serve as a great tool for the design and development of new and efficient molybdenum and tungsten based catalysts for CO2 hydrogenation or HCOOH dehydrogenation.

This study describes the construction of highly-sensitive photo-electrochemical (PEC) immunosensor for the detection of neuron-specific enolase (NSE). The biosensing platform is comprised of photo-active NiWO 4 nanostructures, in-situ-grown over a conductive substrate (indium tin oxide) using a low-temperature template-based co-precipitation approach. The discussed approach enables the formation of discrete, yet morphologically-analogous, nanostructures with complete coverage (pinhole-free) of the electrode surface. The in-situ-grown nanostructure possess dense population with sharp saw-blade like morphological features that can support substantial immobilisation of anti-NSE agent. The constructed platform demonstrated excellent photo-catalytic activity towards uric acid (UA) which served as the base for the Electrochemical -mechanism (EC) based PEC inhibition sensing. The detection of NSE, relied on its obstruction in analytical signal observed for the photo-oxidation of UA after binding to the electrode surface via protein-antibody interaction. The constructed PEC immunosensor exhibits signal sensitivity up to 0.12 ng mL -1 of NSE with excellent signal reproducibility and electrode replicability. Moreover, the constructed platform was successfully used for NSE determination in human serum samples., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Development of high photothermal performance and biocompatible nanotherapeutic agents is of great importance for photothermal cancer treatment. In this paper, we have developed lentinan decorated tungsten oxide nanorods (W 18 O 49 @LTN NRs) via a mild one-step solvothermal route. Owing to the numerous surface hydroxyl groups of polymer chains, the presence of lentinan layer in the surface of W 18 O 49 NRs lead to good biocompatibility. The lentinan layer also affects the crystal structure of W 18 O 49 and improves near-infrared absorption (~1.7 × 10 9  M -1  cm -1 at 980 nm), which is two orders of higher than previously reported PEGylated W 18 O 49 nanowires. Even under near-infrared (NIR) laser irradiation at a very low power density of 0.4 W/cm 2 , the temperature of W 18 O 49 @LTN NRs aqueous dispersion (125 μg/mL) could increase by 15.1 °C. The photothermal conversion efficiency of W 18 O 49 @LTN NRs reaches 33.86%, which is higher than previously reported WO 3-x hierarchical nanostructures (28.1%). Importantly, when cancer cells were treated with W 18 O 49 @LTN NRs (200 μg/mL) and 980 nm laser (0.4 W/cm 2 ), a significant photo-induced cell killing behavior was observed. This work demonstrates that W 18 O 49 @LTN NRs have the potential for precise cancer treatment., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The electrorheological (ER) effect was experimentally observed in dielectric suspensions containing tungsten oxide (WO 3 ) modified with surfactant molecules (sodium dodecyl sulfate (SDS) and dodecylamine (DDA)) in electric fields up to several kilovolts per millimeter. The dielectric properties of WO 3 suspensions in silicone oil were analyzed, depending on the frequency of the electric field, in the range from 25 to 10 6 Hz. Unmodified WO 3 suspensions, as well as suspensions modified with sodium dodecyl sulfate, were shown to exhibit a positive electrorheological effect, whereas suspensions modified with dodecylamine demonstrated a negative electrorheological effect. The quantitative characteristics of the negative electrorheological effect in the strain-compression and shear regimes were obtained for the first time. Visualization experiments were performed to see the chain structures formed by WO 3 particles modified with sodium dodecyl sulfate, as well as for dynamic electroconvection in electrorheological fluids containing WO 3 modified with dodecylamine. The negative electrorheological effect was shown to be associated with the processes of phase separation in the electric field, which led to a multiplicative effect and a strong electroconvection of the suspension at field strengths above 1 kV/mm.

Backgrounds: Profiting from the development of nanomaterials, photothermal therapy (PTT) has been discovered as efficient tumor ablation strategy for breast cancer., Materials and Methods: Novel oxygen vacancy-rich tungsten bronze nanoparticles (Na x WO 3 ) were synthesized through a simple pyrogenic decomposition process. TEM, XRD, UV-vis-NIR, photothermal conversion ability, and photothermal stability were performed. The viabilities of 293T and 4T1 cells after treating with 200 μg/mL Na x WO 3 nanoparticles for 24 or 48 hrs were both above 80%, which proved the good biosafety and cytotoxicity of Na x WO 3 in vitro. Two in vivo breast cancer models, namely percutaneous and intratibial 4T1 models were established and Na x WO 3 (20 mg/kg) with power intensity of 1.5 W/cm 2 980 nm laser photothermal treatment was used in vivo., Results: We successfully synthesized ~150 nm Na x WO 3 nanoparticles with desirable PTT effects, as evidenced by the temperature increase from 25.8°C to 41.8°C in 5 mins under the irradiation of 980 nm laser (1 mg/mL). Also, cellular compatibility of Na x WO 3 nanoparticles was found upon physiologic 293T cells, in contrast with significant cytotoxicity against breast cancer 4T1 cell in vitro dose-dependently. Besides, two in vivo breast cancer models showed the decent tumor ablation ability of Na x WO 3 nanoparticles, demonstrating percutaneous 4T1 tumor elimination without recurrence during 2 weeks observation as well as intratibial breast cancer inhibition with decreased bone destruction and tumor volume after Na x WO 3 +PTT in vivo., Conclusion: For the first time, we developed a novel oxygen vacancy-rich tungsten bronze nanoparticles (Na x WO 3 ) through a simple pyrogenic decomposition process for PTT. Both in vitro and in vivo experiments showed the good PTT ability and tumor ablation effects of synthesized Na x WO 3 nanoparticles against breast cancer osteolytic bone metastasis. Additionally, our oxygen-deficient Na x WO 3 nanoparticles will expand the research horizons of PTT nanomaterials., Competing Interests: The authors report no conflicts of interest in this work., (© 2019 Jie et al.)

Herein, we have reported a simple sonochemical synthesis of multi-layer graphene covered tungsten trioxide nanoballs (WO 3 NBs) and the nanocomposite was characterized by FESEM, HRTEM, XRD, XPS, CV and EIS. Furthermore, progesterone (PGT) is a preferred marker for various biological problems like pregnancy problem, mood swings, anxiety, depression, nervousness and body pain. Therefore, its selective and sensitive determination in various biological fluids is beneficial for the evaluation of malformation problems. We describe the fabrication of an amperometric and non-enzymatic biosensor based on WO 3 NBs@GR nanocomposite modified electrode for nanomolar detection of PGT. The results showed that the nanocomposite modified electrode exhibit well-defined electro-oxidation peak compared to bare and control electrodes, demonstrating the superior electrocatalytic ability and performances. The fabricated modified sensor was facilitates the analysis of PGT in the concentration ranges of 0.025-1792.5 µM with a low detection limit of 4.28 nM. Further, the as-prepared WO 3 NBs@GR electrode has been applied to determination of PGT in human blood samples with outstanding recovery results and more importantly, the facile and environment-friendly sonochemical construction strategy extended here, may be open a cost-effective way for setting up the nanocomposites based (bio) sensing platform., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Pulsed discharge plasma (PDP) was adopted to induce WO 3 for synergetic degradation of ciprofloxacin (CIP) in water. WO 3 was firstly characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS), Photocurrents and Photoluminescence. The degradation results showed that PDP could induce WO 3 photocatalysis successfully, and a synergetic effect was established in PDP/WO 3 system. After 60 min treatment time, 0.16 g/L WO 3 increased the CIP removal from 71.3% to 99.6%, with the enhancement of the first-order kinetic constant from 0.020 min -1 to 0.081 min -1 . Then, the effect of peak voltage, air flow rate and pH on CIP removal was evaluated. Active species trapping test verified that ·OH and ·O 2 - played the major role for plasma-degradation of CIP degradation, whereas OH and h + were conductive to catalytic degrade CIP. WO 3 addition lead to the decline of O 3 and enhancement of OH no matter in deionized water or CIP solution. The degradation process was explored using fluorescence spectrograph, liquid chromatography-mass spectrometry (LC-MS) and ion chromatography (IC). Finally, the possible degradation pathways of CIP degradation were proposed. The reuse test suggested WO 3 possessed excellent catalytic performance as well as good stability., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A strategy for the photoelectrochemical detection of miRNA with ultra-low background noise was developed using tungsten diselenide-cysteine-dopamine (WSe2/Cys/DA) as a nanoprobe coupled with mismatched catalytic hairpin assembly target recycling. A superior detection limit of 3.3 aM toward miRNA-221 was achieved.

Grafting a molybdenum oxo alkylidene on silica (partially dehydroxylated at 700 °C) affords the first example of a well-defined silica-supported Mo oxo alkylidene, which is an analogue of the putative active sites in heterogeneous Mo-based metathesis catalysts. In contrast to its tungsten analogue, which shows poor activity towards terminal olefins because of the formation of a stable off-cycle metallacyclobutane intermediate, the Mo catalyst shows high metathesis activity for both terminal and internal olefins that is consistent with the lower stability of Mo metallacyclobutane intermediates. This Mo oxo metathesis catalyst also outperforms its corresponding neutral silica-supported Mo and W imido analogues., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Various metal oxides were used as co-catalysts to improve the production of alkyl lactate over Sn-Beta-P. WO 3 exhibited the best promotion effect. The yield of MLA increased from 25% (6.5 g L -1 ) over Sn-Beta-P (0.2 g) to 52% (13.4 g L -1 ) over WO 3 (0.1 g) and Sn-Beta-P (0.1 g) at 160 °C for 5 h and 3.1 wt% of glucose concentration. MLA yield of 38% was attained even at glucose concentration of 10 wt% and the space-time yield reached 7.1 g L -1  h -1 . The action mechanism of WO 3 was investigated. Fine WO 3 particles adsorbed on surface of Sn-Beta-P in reaction media and decreased the silanol defects of Sn-Beta-P. This promotes retro-aldol of fructose, the rate-determining step of whole reaction, thus facilitated the formation of MLA. Kinetic studies indicate that the presence of WO 3 decreased the activation energy of the retro-aldol of fructose. The binary solid WO 3 and Sn-Beta-P is recyclable., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

This report outlines an ultrasensitive electrochemiluminescence (ECL) sensing platform based on water-soluble tungsten oxide quantum dots (WO x QDs) for the detection of dopamine (DA) released from P12 cells. The WO x QDs with good stability and water solubility were prepared by a facile and green hydrothermal method, and used to modify a glassy carbon electrode (WO x QDs/GCE). The proposed ECL sensor exhibited a stable and strong cathodic ECL signal when potassium peroxodisulfate (K 2 S 2 O 8 ) as the coreactant in aqueous solution. The possible ECL mechanism was studied and deduced, and the ECL response signal of the proposed sensor decreased rapidly in the presence of dopamine (DA). Under optimal conditions, the ECL signals of WO x QDs linearly decreased with the increase of DA concentration in the range of 10 -15  M to 10 -9  M and 10 -9  M to 10 -5  M, respectively. The detection limit was as low as 10 -15  M (S/N = 3). Based on these results, this method has been successfully applied to the determination of DA released by PC12 cells. The detection linear range for the detection of DA released by PC12 cells was from 0.1 to 0.9 μM with a detection limit of 0.045 μM. Therefore, the proposed ECL sensor displayed high sensitivity, good specificity and long-term stability, which may shed light on a new way to construct other high-performance ECL detection systems based on WO x or WO x QDs-based nanocomposites., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A hydrogel drug cargo based on 2D tungsten nitride nanosheets was fabricated. It exhibits stable NIR-II responsive photothermal properties and drug release behaviour. Moreover, this hydrogel shows excellent tumour ablation efficiency in vivo via NIR-II triggered multiple chemo/photothermal therapy.

The construction of the hierarchical nanostructures of inorganic materials with high stability has attracted great attention for photothermal therapy. In this paper, we presented the preparation of urchin-like LaWO4Cl nanostructures assembled with nanoribbons via a facile solvothermal reaction. X-ray diffraction (XRD) analysis confirmed the formation of good crystalline urchin-like LaWO4Cl assemblies. Energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS) revealed the element composition of the prepared urchin-like nanostructures. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations showed that the urchin-like LaWO4Cl assemblies were composed of single crystalline nanoribbons with diameters less than 10 nm. When excited with an 808 nm near-infrared (NIR) laser at the power density of 1.91 W cm-2 for 5 min, the temperature quickly increased to 52 °C. The in vitro cytotoxicity of urchin-like LaWO4Cl was tested with human cervical cancer cells (HeLa), revealing excellent biocompatibility. More importantly, the photothermal treatment with urchin-like LaWO4Cl displayed great therapeutic efficacy in vitro. Thus, urchin-like LaWO4Cl would be a new promising NIR light-driven photothermal agent, which can also pave a new way for the material design of PTT agents.

By means of electrospinning with the thermal annealing process, we investigate a highly efficient sensing platform driven by a hierarchical hetero-nanostructure for the sensitive detection of biologically relevant molecules, consisting of single crystalline ruthenium dioxide nanorods (RuO 2 NRs) directly grown on the surface of electrospun tungsten trioxide nanofibers (WO 3 NFs). Electrochemical measurements reveal the enhanced electron transfer kinetics at the prepared RuO 2 NRs-WO 3 NFs hetero-nanostructures due to the incorporation of conductive RuO 2 NRs nanostructures with a high surface area, resulting in improved relevant electrochemical sensing performances for detecting H 2 O 2 and L-ascorbic acid with high sensitivity.

Electrochemical energy conversion requires electrodes that can simultaneously facilitate substrate bond activation and electron-proton charge transfer. Traditional electrodes co-localize both functions to a single solid|liquid interface even though each process is typically favored in a disparate reaction environment. Herein, we establish a strategy for spatially separating bond activation and charge transfer by exploiting mixed electron-proton conduction (MEPC) in an oxide membrane. Specifically, we interpose a MEPC WO x membrane between a Pt catalyst and aqueous electrolyte and show that this composite electrode is active for the hydrogen oxidation reaction (HOR). Consistent with H 2 activation occurring at the gas|solid interface, the composite electrode displays HOR current densities over 8-fold larger than the diffusion-limited rate of HOR catalysis at a singular Pt|solution interface. The segregation of bond activation and charge separation steps also confers excellent tolerance to poisons and impurities introduced to the electrolyte. Mechanistic studies establish that H 2 activation at the Pt|gas interface is coupled to the electron-proton charge separation at the WO x |solution interface via rapid H-diffusion in the bulk of the WO x . Consequently, the rate of HOR is principally controlled by the rate of H-spillover at the Pt|WO x boundary. Our results establish MEPC membrane electrodes as a platform for spatially separating the critical bond activation and charge transfer steps of electrocatalysis.

Treatment of liver metastasis experiences slow progress owing to the severe side effects. In this study, we demonstrate a strategy capable of eliminating metastatic cancer cells in a selective manner. Nucleus-targeting W 18 O 49 nanoparticles (WONPs) are conjugated to mitochondria-selective mesoporous silica nanoparticles (MSNs) containing photosensitizer (Ce6) through a Cathepsin B-cleavable peptide. In hepatocytes, upon the laser irradiation, the generated singlet oxygen species are consumed by WONPs, in turn leading to the loss of their photothermally heating capacity, thereby sparing hepatocyte from thermal damage induced by the laser illumination. By contrast, in cancer cells, the cleaved peptide linker allows WONPs and MSNs to respectively target nucleus and mitochondria, where the therapeutic powers could be unleashed, both photodynamically and photothermally. This ensures the energy production of cancer cells can be abolished. We further assess the underlying molecular mechanism at both gene and protein levels to better understand the therapeutic outcome.

Multifunctional nanomaterials that have integrated diagnostic and therapeutic functions and low toxicity, and can enhance treatment efficacy through combination therapy have drawn tremendous amounts of attention. Herein, a newly developed multifunctional theranostic agent is reported, which is PEGylated W-doped TiO 2 (WTO) nanoparticles (NPs) synthesized via a facile organic route, and the results demonstrated strong absorbance of these WTO NPs in the second near-infrared (NIR-II) window due to successful doping with W. These PEGylated WTO NPs can absorb both NIR-II laser and ionizing radiation, rendering them well suited for dual-modal computed tomography/NIR-II photoacoustic imaging and synergistic NIR-II photothermal/radiotherapy of tumors. In addition, the long-term in vivo studies indicated that these PEGylated WTO NPs had no obvious toxicity on mice in vivo, and they can be cleared after a 30-day period. In summary, this multifunctional theranostic agent can absorb both NIR-II laser and ionizing radiation with negligible toxicity and rapid clearance, therefore it has great promise for applications in imaging and therapeutics in biomedicine., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.

The ability to manipulate the structure and function of promising systems via external stimuli is emerging with the development of reconfigurable and programmable multifunctional materials. Increasing antifungal and antitumor activity requires novel, effective treatments to be diligently sought. In this work, the synthesis, characterization, and in vitro biological screening of pure α-Ag 2 WO 4 , irradiated with electrons and with non-focused and focused femtosecond laser beams are reported. We demonstrate, for the first time, that Ag nanoparticles/α-Ag 2 WO 4 composite displays potent antifungal and antitumor activity. This composite had an extreme low inhibition concentration against Candida albicans, cause the modulation of α-Ag 2 WO 4 perform the fungicidal activity more efficient. For tumor activity, it was found that the composite showed a high selectivity against the cancer cells (MB49), thus depleting the populations of cancer cells by necrosis and apoptosis, without the healthy cells (BALB/3T3) being affected.

Dimethyl sulfoxide reductases (DMSO) are molybdoenzymes widespread in all domains of life. They catalyse not only redox reactions, but also hydroxylation/hydration and oxygen transfer processes. Although literature on DMSO is abundant, the biological significance of these enzymes in anaerobic respiration and the molecular mechanisms beyond the expression of genes coding for them are still scarce. In this review, a deep revision of the literature reported on DMSO as well as the use of bioinformatics tools and free software has been developed in order to highlight the relevance of DMSO reductases on anaerobic processes connected to different biogeochemical cycles. Special emphasis has been addressed to DMSO from extremophilic organisms and their role in nitrogen cycle. Besides, an updated overview of phylogeny of DMSOs as well as potential applications of some DMSO reductases on bioremediation approaches are also described.

Single layered two-dimensional (2D) materials such as transition metal dichalcogenides (TMDs) show great potential in many microelectronic or nanoelectronic applications. For example, because of extremely high sensitivity, TMD-based biosensors have become promising candidates for next-generation label-free detection. However, very few studies have been conducted on understanding the fundamental interactions between TMDs and other molecules including biological molecules, making the rational design of TMD-based sensors (including biosensors) difficult. This study focuses on the investigations of the fundamental interactions between proteins and two widely researched single-layered TMDs, MoS 2 , and WS 2 using a combined study with linear vibrational spectroscopy attenuated total reflectance FTIR and nonlinear vibrational spectroscopy sum frequency generation vibrational spectroscopy, supplemented by molecular dynamics simulations. It was concluded that a large surface hydrophobic region in a relatively flat location on the protein surface is required for the protein to adsorb onto a monolayered MoS 2 or WS 2 surface with preferred orientation. No disulfide bond formation between cysteine groups on the protein and MoS 2 or WS 2 was found. The conclusions are general and can be used as guiding principles to engineer proteins to attach to TMDs. The approach adopted here is also applicable to study interactions between other 2D materials and biomolecules.

It is very challenging to fabricate novel, high-efficiency photocatalysts with an enhanced visible light absorption capacity, high charge carrier separation efficiency, and large specific surface area. For this purpose, a yeast-derived carbon (YC) sphere was added as a charge carrier bridge to the 2D-2D Cu 2 WS 4 /g-C 3 N 4 heterojunction through a facile hydrothermal method. The YC sphere, as a bridge for electrons, is not only advantageous in inhibiting rapid recombination by electrons, but also remarkably enhances the visible light absorption capacity. Moreover, the YC sphere can also increase the specific surface area and surface roughness, which can enhance the adsorption of pollutant molecules and provide abundant active sites for photocatalytic reactions. The g-C 3 N 4 /YC/Cu 2 WS 4 heterojunction showed the best photocatalytic activity for reducing hexavalent chromium Cr(VI) and decomposing tetracycline (TC) under visible light. Meanwhile, the acute toxicity of Daphnia magna (D. magna) gradually decreases with the conversion of Cr(VI) to Cr(III) in solution. In addition, the possible intermediate products and the photocatalytic reaction mechanism are revealed in depth. This work provides a general example for improving the photocatalytic activity of 2D-2D based heterojunctions by introducing a biomass material., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Pulsed discharge plasma (PDP) combined with TiO 2 /WO 3 composites for chloramphenicol (CAP) degradation was investigated. The prepared TiO 2 /WO 3 composites were characterized by scanning electron microscope, transmission electron microscope, nitrogen adsorption apparatus, zeta sizer, X-ray diffraction, Raman spectra, UV-Vis absorption spectroscopy, X-ray photoelectron spectroscopy, photocurrent and electrochemical impedance spectroscopy. The degradation performance showed that the addition of TiO 2 /WO 3 composites significantly enhanced the removal efficiency of CAP in PDP system. At a peak voltage of 18 kV, the highest removal efficiency of CAP could reach 88.1% in PDP system with 4 wt% TiO 2 /WO 3 , which was 36.8% and 26.0% higher than that in sole PDP system and PDP/TiO 2 system, respectively. The TiO 2 /WO 3 composites significantly accelerated interfacial charge transfer process compared to the pure TiO 2 . Besides, the effect of catalyst dosage and peak voltage on CAP removal was evaluated. OH, O 3 O 2 - , h + and high-energy electrons contributed to CAP degradation in PDP-TiO 2 /WO 3 system. Addition of TiO 2 /WO 3 composites can decompose O 3 and produce more OH and H 2 O 2 . The degradation intermediates were measured by liquid chromatography-mass spectrometry (LC-MS) and ion chromatography (IC). The cycling degradation experiment showed that the TiO 2 /WO 3 composites have good reusability as well as stability., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this paper, mesoporous tungsten sulfide electrocatalyst (MP-WS 2 ) were developed through a facile sonochemical technique (SC) and utilized as an electrocatalyst for the sensitive electrochemical detection of Psychoactive drug. The as-prepared SC-MP-WS 2 NRs and HT-WS 2 NPs (hydrothermally synthesized) were characterized using XRD, Raman, XPS, FESEM, HRTEM, BET, EDX, and electrochemical analysis, which exposed the formation of WS 2 in the form of mesoporous nanorods in shape. Further, the use of the as-developed SC-MP-WS 2 NRs and HT-WS 2 NPs as an electrocatalyst for the detection of clonazepam (CNP). Interestingly, the SC-MP-WS 2 NRs modified screen-printed carbon electrode (SC-MP-WS 2 NRs/SPCE) exhibited an excellent electrocatalytic performance, and enhanced reduction peak current when compared to HT-WS 2 NPs with unmodified electrode. Moreover, as-prepared SC-MP-WS 2 NRs/SPCE displayed wide linear response range (10-551 µM), lower detection limit (2.37 nM) and high sensitivity (24.32 µAµM -1 cm -2 ). Furthermore, SC-MP-WS 2 NRs/SPCE showed an excellent selectivity even in the existence of potentially co-interfering compounds. The proposed sensor was successfully applied for the determination of CNP in biological and drug samples with acceptable recovery., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background/aim: The aim of the study was to investigate the dosimetric characteristics of electron beams with a tungsten functional paper (TFP) surface collimator., Materials and Methods: The circular field of 6.0 cm diameter was created with the TFP collimator put on the phantom. Depth and lateral dose profiles for 4 and 6 MeV electron beams were obtained. The characteristics of lateral dose profile, treatment diameter as width over 90% of the dose, and penumbra as width of the off-axis positions from 80% to 20% dose levels were evaluated., Results: Compared to the lead collimator, the TFP collimator generated higher surface doses, the treatment diameters were increased from 42.8 to 48.6 mm and from 40.0 to 41.4 mm, and the penumbras were reduced from 15.0 to 9.6 mm and from 16.4 to 13.0 mm for 4 and 6 MeV electron beams, respectively., Conclusion: The TFP surface collimator can provide an excellent dose distribution compared to the conventional lead collimator., (Copyright© 2019, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

An all-solid-state metal-mediated Z-scheme photoelectrochemical (PEC) immunoassay was designed for sensitive detection of prostate-specific antigen (PSA) by using WO 3 -Au-CdS nanocomposite as photoactive material and copper ion (Cu 2+ ) as an inhibitor. The Z-scheme PEC system comprising of CdS nanoparticle (photosystem I; PS I), WO 3 nanorod (photosystem II; PS II) and gold nanoparticle (Au NP; solid electron mediator) was reasonably established by a simple and green synthetic method. As an important part of Z-scheme system, the sandwiched gold nanoparticles between electron donor materials and hole provider materials could accelerate electron transfer from positive conduction band (CB) of WO 3 to negative valence band (VB) of CdS, thus resulting in high-efficient separation of the carriers. In the presence of target PSA, a sandwiched immunoreaction was executed between capture antibody-coated microplate and CuO nanoparticle-labeled detection antibody. Thereafter, CuO nano labels were dissolved into Cu 2+ ions under acidic condition to decrease the photocurrent of Z-scheme WO 3 -Au-CdS thanks to the formation of exciton trapping center of Cu x S (x = 1,2) on the surface. Under optimum conditions, Z-scheme PEC immunoassay exhibited good photocurrents toward target PSA within a linear range of 0.01-50 ng mL -1 at a limit of detection of 1.8 pg mL -1 . Moreover, the Z-scheme PEC immunoassay had high selectivity and accuracy. Importantly, this method provides a new horizon for detection of disease-related biomarkers with high sensitivity., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background/aim: Spatially fractionated radiotherapy (grid therapy) can control some bulky tumors which is challenging for conventional radiotherapy. This study aimed to investigate whether a novel tungsten contained rubber (TCR) grid collimator can be employed in electron grid therapy., Materials and Methods: The TCR grid collimator placed on a solid water phantom, and percentage depth doses (PDDs) and lateral dose profiles were measured for 9 MeV electron beam with Gafchromic EBT3 films. At the lateral dose profile, the ratios of the dose in the areas with and without shielding (valley-to-peak ratios) were evaluated., Results: The d max values with the 1, 2 and 3 mm TCR grid collimators were 1.2, 1.1 and 0.7 cm, respectively, while the valley-to-peak ratios at each d max were 0.566, 0.412 and 0.293, respectively., Conclusion: Only the 2 mm TCR grid collimator had adequate dosimetric features compared to the conventional grid collimator and could be substituted., (Copyright© 2019, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Sonodynamic therapy (SDT) triggered by ultrasound (US) has attracted increasing attention owing to its abilities to overcome critical limitations including low tissue-penetration depth and phototoxicity in photodynamic therapy. Herein, the design of a new type of sonosensitizer is revealed, namely, ultrasmall oxygen-deficient bimetallic oxide MnWO X nanoparticles, for multimodal imaging-guided enhanced SDT against cancer. As-made MnWO X nanoparticles with poly(ethylene glycol) (PEG) modification show high physiological stability and biocompatibility. Interestingly, such MnWO X -PEG nanoparticles exhibit highly efficient US-triggered production of 1 O 2 and •OH, higher than that of previously reported sonosensitizers (e.g., protoporphyrin IX and titanium dioxide), because the oxygen-deficient structure of MnWO X serves as an electron trap site to prevent electron-hole recombination. The glutathione depletion capability of MnWO X -PEG can also further favor SDT-triggered cancer cell killing. With efficient tumor homing as illustrated by computer tomography and magnetic resonance imaging, MnWO X -PEG enables effective destruction of mouse tumors under US stimulation. After accomplishing its therapeutic functions, MnWO X -PEG can be metabolized by the mouse body without any long-term toxicity. Herein, a new type of sono-sensitizing agent with high SDT efficacy, multimodal imaging functions, and rapid clearance is presented, an agent which is promising for noninvasive SDT cancer treatment., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The novel method was developed for electrochemical cancer cell detection using CuO/WO 3 nanoparticle decorated graphene oxide nanosheet (CuO/WO 3 -GO) with enhanced peroxidase like-activity, based on catalytic reaction of H 2 O 2 with o-Phenylenediamine (OPD). The prepared nanocomposite conjugated with folic acid (FA), as a cancer cell-targeting ligand, and a miniaturized electrochemical cell for cancer cell detection was designed. In this strategy OPD could oxidize in the presence of H 2 O 2 on the surface of working electrode, which produced an electrochemical signal. However, the redox response signal changed by interaction of cells with FA/CuO/WO 3 -GO. During interaction between cells and CuO/WO 3 -GO, some amount of H 2 O 2 -OPD system participated in chemical reaction and removed from the electrode, resulting in a decrease in the response signal. As a consequence, cancer cells detected in wide detection range of 50 to 10 5 cells/mL and a detection limit of 18 cells/mL. Furthermore, the nanocomposite shows therapeutic cancer treatment through superior peroxidase activity. This work unveils an effective method for simple, sensitive and selective monitoring of cancer cells and also has the potential for efficient cancer therapy, which will open an avenue of nanozymes toward biological applications., (Copyright © 2019 Elsevier B.V. All rights reserved.)

As artificial synapses in biomimetics, memristors have received increasing attention because of their great potential in brain-inspired neuromorphic computing. The use of biocompatible and degradable materials as the active resistive layer is promising in memristor fabrication. In this work, we select egg albumen as the resistive layer to fabricate flexible tungsten/egg albumen/indium tin oxide/polyethylene terephthalate devices, which can operate normally under mechanical bending without significant performance degradation. This proposed memristor device exhibits a transparency of more than 90% under visible light with a wavelength range of 230-850 nm. Moreover, by changing amplitudes of pulse voltage instead of intervals, paired-pulse facilitation can be transmitted to paired-pulse depression, which can faithfully mimic dynamical balance of Ca 2+ concentration shaped by voltage-sensitive calcium channels. The device resistance can be modulated gradually by applied pulse trains to mimic certain neural bionic behaviors, including excitatory postsynaptic current, short-term plasticity (STP) and long-term plasticity (LTP), and transitions between STP and LTP. The reasons behind these behaviors are analyzed through power consumption calculation. Excellent biosimulation characteristics have been demonstrated in this egg albumen-based memristor device, which is desirable in biocompatible and dissolvable electronics for flexible artificial neuromorphic systems.

We report a tungsten disulfide (WS 2 ) nanosheet-immobilized hydrogel system that can inhibit oxidative stress on living cells. First, we fabricated a highly stable suspension of WS 2 nanosheets as a radical scavenger by enveloping them with the amphiphilic poly(ε-caprolactone)- b-poly(ethylene oxide) copolymer (PCL- b-PEO) during in situ liquid exfoliation in aqueous medium. After the PCL- b-PEO-enveloped WS 2 nanosheets were embedded in three types of hydrogel systems, including carrageenan gum/locust bean gum bulk hydrogels, physically cross-linked alginate microparticles, and covalently cross-linked PEG hydrogel microparticles, they retained their characteristic optical properties. Intriguingly, the WS 2 nanosheet-immobilized hydrogel particles exhibited sustainable radical scavenging performance without any deterioration in the original activity of the WS 2 nanosheets, even after repeated use. This implies that the hydrogen atoms dissociated from the chalcogen of the WS 2 nanosheets effectively scavenged free radicals through the hydrogel mesh. Because of this unique behavior, the coexistence of the WS 2 nanosheets with living cells in the hydrogel matrix improved cell viability up to 40%, which demonstrates that the WS 2 nanosheets can suppress oxidative stress on living cells.

Pinhole collimation is widely recognized for offering superior resolution-sensitivity trade-off in SPECT imaging of small subjects. The newly developed EXIRAD-3D autoradiography technique (MILabs B.V.) based on a highly focusing multi-pinhole collimator achieves micron-resolution SPECT for cryo-cooled tissue samples. For such high resolutions, the choice of pinhole material may have a significant impact on images. Therefore, this paper aims to compare the performance of EXIRAD-3D with lead, tungsten, gold, and depleted uranium pinhole collimators designed such that they achieve equal sensitivities. Performance in terms of resolution is characterized for several radioisotopes, namely 111 In (171 keV and 245 keV), 99m Tc (140 keV), 201 Tl (71 keV), and 125 I (27 keV). Using Monte Carlo simulation, point spread functions were generated and their profiles as well as their full-width-at-half-maximum and full-width-at-tenth-maximum were determined and evaluated for different materials and isotopes. Additionally, simulated reconstructions of a Derenzo resolution phantom, validated with experimental data, were judged by assessment of the resolvable rods as well as a contrast-to-noise ratio (CNR) analysis. Our results indicate that using materials with higher photon-stopping power yields images with better CNR for the studied isotopes with improvements ranging from 1.9% to 36.6%. Visual assessment on the reconstructed images suggests that for EXIRAD-3D, the tungsten collimator is generally a good choice for a wide range of SPECT isotopes. For relatively high-energy isotopes such as 111 In, using gold inserts can be beneficial.

The potential risks associated with two-dimensional (2D) nanomaterials may cause serious concerns about their real applications and impact in biological systems. In addition, the demonstration of biodegradability of these flat nanomaterials is essential in living organisms. Here, we summarise the state-of-the-art in the field of biocompatibility and biodegradability of graphene-related materials (such as 2D materials like MoS2, BN or WS2). The impact of chemical functionalisation on the potential control of the biodegradability profile of these structures is also discussed.

In this work, primidone, a high persistent pharmacological drug typically found in urban wastewaters, was degraded by different ozone combined AOPs using TiO 2 P25 and commercial WO 3 as photocatalyst. The comparison of processes, kinetics, nature of transformation products, and ecotoxicity of treated water samples, as well as the influence of the water matrix (ultrapure water or a secondary effluent), is presented and discussed. In presence of ozone, primidone is rapidly eliminated, with hydroxyl radicals being the main species involved. TiO 2 was the most active catalyst regardless of the water matrix and the type of solar (global or visible) radiation applied. The synergy between ozone and photocatalysis (photocatalytic ozonation) for TOC removal was more evident at low O 3 doses. In spite of having a lower band gap than TiO 2 P25, WO 3 did not bring any beneficial effects compared to TiO 2 P25 regarding PRM and TOC removal. Based on the transformation products identified during ozonation and photocatalytic ozonation of primidone (hydroxyprimidone, phenyl-ethyl-malonamide, and 5-ethyldihydropirimidine-4,6(1H,5H)-dione), a degradation pathway is proposed. The application of the different processes resulted in an environmentally safe effluent for Daphnia magna .

This work characterizes a previously undetected epimerization in the preparation of alkynyl diols from pentose precursors utilizing the Ohira-Bestmann reagent. Lithium trimethylsilyldiazomethane (Colvin reagent) additions to the d-ribose and d-lyxose-derived benzylidene acetals provide the respective alkynyl diol stereoisomers, without epimerization. Regioselective tungsten-catalyzed cycloisomerizations of the d-ribose- and d-lyxose-derived alkynyl diols yield rigid bicyclic pyranose glycals, confirming the stereochemical fidelity of the Colvin alkynylation process.

As a carcinogenic byproduct in drinking water treatment, bromate has raised global concerns on environmental and health hazard, calling for effective treatments. In the current work, a novel reduced graphene oxide supported polyaniline/WO 2.72 nanobelt-flower (RGO/PANI/WO 2.72 ) ternary composite was prepared through a solvent volatilization method for photocatalytic reduction of bromate. The prepared sample was characterized, and the influence of aqueous pH, ions and dissolved oxygen on the bromate reduction was explored. As expected, the introduction of RGO and PANI on the WO 2.72 exhibited great synergistic effects on the separation of photogenerated carriers. The calculated reduction rate constant of RGO/PANI/WO 2.72 was about six times as high as that of pure WO 2.72 . Specially, the prepared photocatalyst possessed strong optical absorption in a broad range of 250-2500 nm, and thus displaying excellent catalytic performance in utilization of all solar spectrum energy. Moreover, the RGO/PANI/WO 2.72 exhibited stable photocatalytic activity in cycling test. Considered holistically, the present study offered a valuable approach for rational construction of heterogeneous structure in the development of bromate-catalyzed reduction., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The purpose of this study was to evaluate the x-ray shielding ability of a novel tungsten-particle-containing rubber-based finger sack for use in interventional radiology. Shielding rates for the air kerma (mGy m) were measured using a semiconductor dosimeter with and without the finger sack and commercial lead gloves, at a 20 cm distance from the field of view. A C-arm digital angiography system was used with x-ray tube voltages of 60, 80, 100, and 120 kVp. In addition, the 70 μm dose equivalent to the operator's finger was measured using fluorescent glass dosimeters with and without the finger sack during interventional radiology examinations. The x-ray shielding rates for 60, 80, 100, and 120 kV x rays were 98.0 ± 0.03%, 94.8 ± 0.05%, 92.3 ± 0.12%, and 90.1 ± 0.03%, respectively, with the finger sack and 69.8 ± 0.39%, 61.0 ± 0.53%, 52.3 ± 0.52%, and 47.0 ± 0.69% with the lead gloves. The x-ray shielding rates for the fluoroscopy and cine mode with the finger sack were 91.3 ± 0.21% and 56.5 ± 0.58%, respectively, while with the lead gloves they were 96.5 ± 0.04% and 67.6 ± 0.33%. The 70 μm dose equivalent for the operator's finger exposure dose was reduced by approximately 39.4% using the finger sack. The finger shields were more user friendly, had excellent radiation shielding ability against x rays, and should reduce finger exposure in interventional radiology.

Background: Iron oxide nanocomposites have received a great attention for their application in various fields like physics, medicine, biology, and material science etc., due to their unique properties, such as magnetism, electrical properties, small size, biocompatibility and low toxicity., Methods: Fe 3 O 4 /Ag 3 PO 4 @WO 3 nanocomposites with different weight percent of Ag 3 PO 4 were successfully prepared through fabricated Ag 3 PO 4 /Fe 3 O 4 with WO 3 via in situ fabrication method, electrospinning involved precursor solution preparation and spinning to enhance photocatalyst performance under simulated sunlight for the degradation of methylene blue (MB) and antibacterial activity against Staphylococcus aureus (S. aureus)., Results: The photocatalytic degradation of methylene blue (MB) under simulated light irradiation indicated that the nanocomposite with 0.25 mg of Ag 3 PO 4 has the best activity. An additional advantage of these photocatalysts is magnetic recoverability, using external magnetic field and photocatalytic stability of the nanocomposites was evaluated for three cycles. In addition, using different scavengers, holes (h + ) and superoxide radical (O 2 ·-) radicals and hydroxide radical ( · OH) were identified the main oxidative species in the degradation reaction of methylene blue., Conclusions: The results reveal that Fe 3 O 4 /Ag 3 PO 4 @WO 3 -0.25 nanocomposites have photocatalytic and antibacterial activity against S. aureus. The photocatalyst and mechanism based on the enhancement of electron transfer processes between Ag 3 PO 4 and WO 3 nanoparticles.

In this work, CuWO 4 is prepared and its effect of improving photocatalytic degradation of atrazine by TiO 2 as well as the synergetic mechanism is studied. Results show that the addition of CuWO 4 (50 mg/L) into the reaction system can significantly enhance the efficiency of atrazine degradation, resulting in an increased degradation efficiency of 92.1% after 270 min, which is 1.94 times higher than that of the single TiO 2 . As the sintering temperate of CuWO 4 was increased, the degradation efficiency of atrazine increased initially and then deceased after reaching a maximum at 500 °C. The origin of the synergistic effect of TiO 2 -CuWO 4 is attributed to the introduction of solid CuWO 4 . The photochemical test results indicate that the photogenerated electrons transfer from irradiated TiO 2 to CuWO 4 , which is beneficial to the O 2 reduction and H 2 O 2 formation in aqueous solution thus promoting the photocatalytic activity of TiO 2 . These observations unveil the importance of improving photocatalytic activity of TiO 2 with Cu-bearing semiconductors.

Two-dimensional (2D) tungsten disulfide (WS 2 ) quantum dots offer numerous promising applications in materials and optoelectronic sciences. Additionally, the catalytic and photoluminescence properties of ultra-small WS 2 nanoparticles are of potential interest in biomedical sciences. Addressing the use of WS 2 in the context of infection, the present study describes the conjugation of two potent antimicrobial peptides with WS 2 quantum dots, as well as the application of the resulting conjugates in antimicrobial therapy and bioimaging. In doing so, we determined the three-dimensional solution structure of the quantum dot-conjugated antimicrobial peptide by a series of high-resolution nuclear magnetic resonance (NMR) techniques, correlating this to the disruption of both model lipid and bacterial membranes, and to several key biological performances, including antimicrobial and anti-biofilm effects, as well as cell toxicity. The results demonstrate that particle conjugation enhances the antimicrobial and anti-biofilm potency of these peptides, effects inferred to be due to multi-dendate interactions for the conjugated peptides. As such, our study provides information on the mode-of-action of such conjugates, laying the foundation for their potential use in treatment and monitoring of infections., (Copyright © 2019 Elsevier B.V. All rights reserved.)