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To investigate the mechanism of Triton X-100 (TX-100) reducing the Ag+-resistance of Enterococcus faecalis (E. faecalis), and evaluate the antibacterial effect of TX-100 + Ag+ against the induced Ag+-resistant E. faecalis (AREf). The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of AgNO3 against E. faecalis with/without TX-100 were determined to verify the enhanced antibacterial activity. Transmission electron microscopy (TEM) was used to observe the morphological changes of E. faecalis after treatment. The intra- and extracellular concentration of Ag+ in treated E. faecalis was evaluated using inductively coupled plasma mass spectrometer (ICP-MS). The changes in cell membrane potential and integrity of treated E. faecalis were also observed using the flow cytometer. Moreover, AREf was induced through continuous exposure to sub-MIC of Ag+ and the antibacterial effect of TX-100 + Ag+ on AREf was further evaluated. The addition of 0.04% TX-100 showed maximal enhanced antibacterial effect of Ag+ against E. faecalis. The TEM and ICP-MS results demonstrated that TX-100 could facilitate Ag+ to enter E. faecalis through changing the membrane structure and integrity. Flow cytometry further showed the effect of TX-100 on membrane potential and permeability of E. faecalis. In addition, the enhanced antibacterial effect of TX-100 + Ag+ was also confirmed on induced AREf. TX-100 can facilitate Ag+ to enter E. faecalis through disrupting the membrane structure and changing the membrane potential and permeability, thus reducing the Ag+-resistance of E. faecalis and enhancing the antibacterial effect against either normal E. faecalis or induced AREf. [ABSTRACT FROM AUTHOR]

Designing hybrid transition metal compounds with optimized electronic structure and firmly dispersing them on a matrix to avoid aggregation and shedding is of great significance for achieving high electrocatalytic performances. Herein, an adsorption-complexation-calcination strategy based on channel confining effect is explored to obtain CoN-CoOx hybrid nanoparticles uniformly dispersed in mesoporous carbon. The CoN-CoOx/C composite exhibits excellent electrocatalytic behavior for oxygen reduction reaction (ORR). The half-wave potential and durability are comparable or superior to those of Pt/C. When applying as cathode catalyst for a primary zinc-air battery, the open-circuit voltage and peak power density reach up to 1.394 V and 109.8 mW·cm−2, respectively. A high gravimetric energy density of 950.3 Wh·kgZn−1 is delivered at 10 mA·cm−2 with good rate capability and stability. Density functional theory (DFT) calculation demonstrates the favorable ORR intermediate adsorbability and metallic characteristics of CoN grains with oxide hybridization to optimize the electronic structure. This work provides a facile adjustable approach for obtaining highly dispersed nanoparticles with controllable hybrid composition on a substrate, which is important for future design and optimization of high-performance electrocatalysts. [ABSTRACT FROM AUTHOR]

Developing suitable electrode materials for electrochemical energy storage devices by biomorph assisted design has become a fascinating topic due to the fantastic properties derived from bio-architectures. Herein, zephyranthes-like Co2NiSe4 arrays grown on butterfly wings derived three-dimensional (3D) carbon framework (Z-Co2NiSe4/BWC) is fabricated via hydrothermal assembly and further conversion method. Benefiting from its unique structure and multi-components, the obtained Z-Co2NiSe4/BWC electrode for supercapacitor delivers an excellent specific capacitance of 2,280 F·g−1 at 1 A·g−1. Impressively, the constructed asymmetric supercapacitor using Co2NiSe4/BWC as positive electrode and activated butterfly wings carbon as negative electrode acquires a high energy density of 42.9 Wh·kg−1 at a power density of 800 W·kg−1 with robust stability of 94.6% capacitance retention at 10 A·g−1 after 5,000 cycles. Moreover, the Z-Co2NiSe4/BWC as anode for sodium-ion batteries exhibits a high specific capacity of 568 mAh·g−1 at 0.1 A·g−1 and high cycling stability (maintaining 80.1% of the second cycle after 100 cycles). The outstanding electrochemical performances are ascribed to that the synergistic effect of bimetallic selenides and N-doped carbon improves electrochemical activities and conductivity. One-dimensional (1D) nanoneedles grown on 3D porous framework increase the exposure of redox-active sites, endow adequate transmission channels of electrons/ions, and guarantee stability of the electrode during charge/discharge processes. This study will shed light on the avenue towards extending such nanohybrids to excellent energy storage applications. [ABSTRACT FROM AUTHOR]

To solve the problem of low conductivity of sulfur and "shuttle effect" of lithium polysulfides, CoSnO3 nanocubes wrapped by carbon nanofibers (CoSnO3@CNFs) are synthesized by co‐precipitation, electrospinning and calcination techniques. CoSnO3 provides plentiful polar active sites, which restrains the dissolution of polysulfides with chemical interaction. Carbon nanofibers not only provide more ion transport channels, but also increase physical adsorption, provide active sites, and improve the conductivity of the electrode material. As a result, CoSnO3@CNFs can carry about 60 % sulfur as guest. Evaluated as cathode material for lithium‐sulfur batteries, CoSnO3@CNFs/S displayed an initial discharge capacity of 554.9 mA h g−1 at 0.2 C, and retained 300.0 mA h g−1 after 200 cycles. The simple synthesis method, high sulfur loading capacity and long cycle life make CoSnO3@CNFs extremely attractive for practical applications. [ABSTRACT FROM AUTHOR]

Enterococcus faecalis (E. faecalis) is one of the dominant bacteria for refractory infections of teeth. Silver ions (Ag+) have been proved to be a strong bactericide but with high cytotoxicity and discoloration property. Simvastatin is an agent used for dyslipidemia treatment and has anti-inflammatory property. In this study, Ag+ and simvastatin were for the first time used in combination, and poly (lactide-co-glycolide) (PLGA) submicron particles carrying both Ag+ and simvastatin (AgS-PLGA) were fabricated for further investigations. Results confirmed the enhanced antibacterial activity against E. faecalis of Ag+ by simvastatin. AgS-PLGA could release both Ag+ and simvastatin for 24 days and also showed enhanced antibacterial activities. On dentin slices, AgS-PLGA could enter dentinal tubules by ultrasonic activation and inhibit the colonization of E. faecalis. AgS-PLGA showed no cytotoxicity on MC3T3-E1 cells and slight suppressive effect on RAW-264.7 cells, and could reduce the secretion of IL-6 and IL-1β of RAW-264.7 cells. AgS-PLGA could be developed as a new biomaterial for infection and inflammation control for dental and related medical treatments. [ABSTRACT FROM AUTHOR]

Searching for efficient non‐noble metal electrocatalyst for oxygen reduction reaction (ORR) has become a hot topic in electrochemical field. Herein, duck blood containing heme (a type of ferriporphyrin) is carbonized and activated to obtain Fe, N doped carbon. The activated carbonized blood (a‐CB) exhibits an extremely high specific surface area of 2655 m2 g–1. Then, Co3O4 nanoparticles are loaded on the efficient substrate via hydrothermal method. The as obtained Co3O4/a‐CB composite exhibits good catalytic performance for ORR. The onset and half‐wave potentials are 0.95 and 0.77 V vs. RHE, respectively. These values are comparable to those of commercial Pt/C (20 wt.‐%) catalyst. What's more, Co3O4/a‐CB shows better durability and methanol tolerance than commercial Pt/C, making it a promising electrocatalyst for ORR. Compared to artificial porous heteroatom doped carbon materials, this work seeks raw materials from natural biomass waste to obtain efficient carbon substrate with both high porosity and Fe, N self‐doping feature for catalyst applications. [ABSTRACT FROM AUTHOR]

To address low electrical conductivity of sulfur and "poly‐sulfide shuttle" for constructing sulfur hosts with excellent cyclic stability, CoSnO3/CNTs composites are successfully synthesized by combining CoSnO3 cubes and carbon nanotubes (CNTs) via coprecipitation and annealing process. CoSnO3 cubes are bound by continuous carbon nanotube networks, with high specific surface area and vast mesoporous. CoSnO3 with multiple polar active sites has a strong chemical adsorption effect on lithium polysulfide, suppressing the shuttle effect. The carbon nanotubes have continuous conductive networks, which can provide physical confinement with polysulfides and good electrical conductivity. Through the effective combination of advantages of CoSnO3 and carbon nanotubes, CoSnO3/CNTs/S exhibits excellent sulfur storage performance. The maximum discharge capacity of CoSnO3/CNTs/S is 453.3 mAh g−1 at a current density of 0.2 C. After 500 cycles, the discharge specific capacity is still 377.7 mAh g−1. The simple synthesis of CoSnO3/CNTs/S with long cycle life provides a new direction for the future LSBs cathode material research. [ABSTRACT FROM AUTHOR]

Mesoporous calcium-silicate nanoparticles (MCSNs) are excellent biomaterials for controlled drug delivery and mineralization induction. In this study, MCSNs were loaded with low-dose silver ion (Ag+) and Triton X-100 (TX-100) as the M-AgTX to achieve both enhanced antibacterial properties and low cytotoxicity for dentin disinfection. The physicochemical property, biocompatibility, infiltration ability into dentinal tubules, anti-bacterial ability against both planktonic Enterococcusfaecalis (E. faecalis) and its biofilm on dentin, effects on dentin microhardness and in vitro mineralization property were systematically investigated. Results confirmed that the MCSNs and M-AgTX nanoparticles showed typical morphology of mesoporous materials and exhibited sustained release of chemicals with an alkaline pH value over time. M-AgTX also exhibited excellent biocompatibility on MC3T3-E1 cells and could eliminate 100% planktonic E. faecalis after 48-h treatment. On dentin slices, it could enter dentinal tubules by ultrasonic activation and inhibit the growth of E. faecalis on dentin. M-AgTX could completely inactive 28-day E. faecalis biofilm. TEM confirmed the destruction of cell membrane integrity and Ag+ infiltration into bacteria by M-AgTX. Besides, dentin slices medicated with M-AgTX nanoparticles displayed an increased microhardness. After being immersed in SBF for 7 days, apatite crystals could be observed on the surface of the material tablets. M-AgTX could be developed into a new multifunctional intra-canal medication or bone defect filling material for infected bone defects due to its sustained release profile, low cytotoxicity, infiltration ability, enhanced anti-bacterial and mineralization features. [ABSTRACT FROM AUTHOR]

Enterococcus faecalis (E. faecalis) is one of the dominant bacteria for refractory infections of teeth. Silver ions (Ag + ) have been proved to be a strong bactericide but with high cytotoxicity and discoloration property. Simvastatin is an agent used for dyslipidemia treatment and has anti-inflammatory property. In this study, Ag + and simvastatin were for the first time used in combination, and poly (lactide-co-glycolide) (PLGA) submicron particles carrying both Ag + and simvastatin (AgS-PLGA) were fabricated for further investigations. Results confirmed the enhanced antibacterial activity against E. faecalis of Ag + by simvastatin. AgS-PLGA could release both Ag + and simvastatin for 24 days and also showed enhanced antibacterial activities. On dentin slices, AgS-PLGA could enter dentinal tubules by ultrasonic activation and inhibit the colonization of E. faecalis . AgS-PLGA showed no cytotoxicity on MC3T3-E1 cells and slight suppressive effect on RAW-264.7 cells, and could reduce the secretion of IL-6 and IL-1β of RAW-264.7 cells. AgS-PLGA could be developed as a new biomaterial for infection and inflammation control for dental and related medical treatments.