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Dissolved oxygen (DO) is a primary corrosive substance in the transportation process of urban reclaimed water by pipelines. MCM-41 is widely used as a catalyst carrier because of its high specific surface area and low mass transfer resistance. The catalyst, namely Cu/Al-MCM-41 was prepared by doping Cu and Al in MCM-41 using one-step hydrothermal method and was used to catalyze reducing DO in reclaimed water by carbohydrazide. The effects of reaction temperature, the mass concentration of carbohydrazide, the initial pH value of water, and the mass concentration of catalyst on the removal rate of DO from reclaimed water were investigated in this paper. The reusability and catalytic mechanism of Cu/Al-MCM-41, the fresh catalyst, were determined and the used catalyst was characterized by XRD, FTIR, SEM, NH3-TPD, and BET methods. It was concluded that Cu and Al were successfully doped into MCM-41, and the synthesized molecular sieves had a highly ordered hexagonal mesoporous structure. Moreover, the doping of Al metal into MCM-41 improved the acid strength and acid centers significantly. The DO removal rate could reach 98.54% under the temperature of 45 °C, which is 3 times the theoretical feed amount of carbohydrazide, at the initial pH value of 8.5 and the mass concentration of 0.7 g L−1 of the catalyst after 60 min. The Cu/Al-MCM-41 catalyst still showed high catalytic activity after three tests. The active metal Cu could catalyze the decomposition of carbohydrazide into carbon dioxide, nitrogen, and hydrogen atoms The increase of hydrogen atom concentration adsorbed on the catalyst surface led to the rapid reduction of DO.

A high-throughput investigation of metallic glass formation via solid-state reaction was reported in this paper. Combinatorial multilayered thin-film chips covering the entire Ti–Ni–Cu ternary system were prepared using ion beam sputtering technique. Microbeam synchrotron X-ray diffraction (XRD) and X-ray fluorescence (XRF) measurements were conducted, with 1,325 data points collected from each chip, to map out the composition and the phase constitution before and after annealing at 373 K for 110 hours. The composition dependence of the crystal-to-glass transition by solid-state reaction was surveyed using this approach. The resulting composition–phase map is consistent with previously reported results. Time-of-flight secondary ion mass spectroscopy (ToF-SIMS) was performed on the representative compositions to determine the inter-diffusion between layers, the result shows that the diffusion of Ti is the key factor for the crystal-to-glass transition. In addition, both layer thickness and layer sequence play important roles as well. This work demonstrates that combinatorial chip technique is an efficient way for systematic and rapid study of crystal-to-glass transition for multi-component alloy systems.

A novel theranostic prodrug was designed and synthesized by conjugating a naphthalimide derivative with vitamin D2 via a disulfide linker. The prodrug featured a highly selective detection process for glutathione (GSH) and showed a red-shifted fluorescence within 30 min. Notably, it also exhibited antitumor activity similar to vitamin D2 and could be monitored by cellular imaging.

A novel and efficient approach for the synthesis of 1α, 24( R )-dihydroxyvitamin D 3 (tacalcitol) starting from readily available enone 1 has been achieved with high stereoselectivity. The key step involved in the synthesis of tacalcitol was the stereoselective reduction of enone 1 using borane as the reducing agent, and the effects of the critical reaction parameters such as temperature, various borane complexes have been examined. Finally, tacalcitol was obtained in five steps from enone 1 with an overall yield of 32% and a ratio of 24- R / S = 95/5.

Endophthalmitis, derived from the infections of pathogens, is a common complication during the use of ophthalmology-related biomaterials and after ophthalmic surgery. Herein, aiming at efficient photodynamic therapy (PDT) of bacterial infections and biofilm eradication of endophthalmitis, a pH-responsive zeolitic imidazolate framework-8-polyacrylic acid (ZIF-8-PAA) material is constructed for bacterial infection-targeted delivery of ammonium methylbenzene blue (MB), a broad-spectrum photosensitizer antibacterial agent. Polyacrylic acid (PAA) is incorporated into the system to achieve higher pH responsiveness and better drug loading capacity. MB-loaded ZIF-8-PAA nanoparticles are modified with AgNO3 /dopamine for in situ reduction of AgNO3 to silver nanoparticles (AgNPs), followed by a secondary modification with vancomycin/NH2 -polyethylene glycol (Van/NH2 -PEG), leading to the formation of a composite nanomaterial, ZIF-8-PAA-MB@AgNPs@Van-PEG. Dynamic light scattering, transmission electron microscopy, and UV-vis spectral analysis are used to explore the nanoparticles synthesis, drug loading and release, and related material properties. In terms of biological performance, in vitro antibacterial studies against three kinds of bacteria, i.e., Escherichia coli, Staphylococcus aureus, and methicillin-resistant S. aureus, suggest an obvious superiority of PDT/AgNPs to any single strategy. Both in vitro retinal pigment epithelium cellular biocompatibility experiments and in vivo mice endophthalmitis models verify the biocompatibility and antibacterial function of the composite nanomaterials.

In recent decades, bacterial and viral infections and chronic inflammatory response have emerged as important causes of cancer. Also, infections remain a significant cause of morbidity and mortality in cancer patients. In this work, carboxymethyl chitosan nanoparticles (CMC NPs) were synthesized in a facile and green way and further combined with ammonium methylbenzene blue (MB) as a cross-linking agent as well as a fluorescent molecule and a photosensitizer for self-imaging photodynamic therapy (PDT). The obtained CMC-MB NPs exhibited an apparent pH-responsive release behavior of MB, which was released for a prolonged period in a simulated physiological environment (pH 7.4) for more than 15 days and the time reduced to only 3.5 h in acidic conditions (pH 5.5). When irradiated by a 650 nm laser at 202 mW/cm2 for 5 min, the CMC-MB NPs showed efficient bactericidal and biofilm eradication properties as well as suppression of tumor cell growth in a similar acidified microenvironment. Furthermore, in an in vivo rabbit wound bacterial infection model, the rapid sterilization of CMC-MB NPs played a crucial role in bacterial infections, inflammation inhibition, and wound healing. As a PDT treatment against cancer, the CMC-MB NPs also exhibited an efficient antitumor therapeutic effect in a subcutaneous tumor mice model.

Sepsis and implant-related bacterial infections are mainly caused by Gram-positive bacteria accompanied with the notorious drug resistance and biofilms formation. Although the recently concerned photothermal therapy (PTT) shows good performance in killing of planktonic bacteria and removal of biofilms, the issue of potential thermal damage to normal tissue is urgent to be solved due to the non-targeting to bacteria. Here, we constructed a chiral glutamic acid functionalized gold nanobipyramids (Au NBPs) for enhanced PTT against bacterial and biofilms infections based on both chemical and physical interactions with bacteria. Specifically, the conjugation of d / l -glutamic acid ( d / l -Glu) obviously enhanced the targeting and interactions of Au NBPs with bacterial cell wall leading to the biological restriction of nucleic acids. While the sharp tips and small size of Au NBPs enabled the penetration into bacterial cell wall and biofilms for cicada's wings bionic damage to bacterial cell wall and leakage of components. Furthermore, antibacterial mechanism examination confirmed the chemical and physical effects of d / l -Glu and nanobipyramids structure leading to the considerable DNA and nucleic acids leakage, which was greatly enhanced during PTT treatment. Both in vitro and in vivo antibacterial and anti-biofilms measurements verified high efficiency in killing of bacteria and eliminating of biofilms through a synergistic chemotherapy, physiotherapy and PTT functions. Furthermore, the quick targeting of chiral Au NBPs to the bacteria and penetrating into extracellular matrix effectively avoided the nonspecific damage to normal cells. Therefore, this work provides a novel strategy to combat bacterial and biofilms infections in a more smart way owing to the chiral amino acid modification and synergistic antibacterial effects.

Various complications such as posterior capsule opacification (PCO) and endophthalmitis occur after intraocular lenses (IOLs) implantation in cataract surgery. It is urgent to construct antifouling and antibacterial IOLs to lower the incidence of PCO and endophthalmitis. Bionic zwitterionic polymer such as 2-methacryloyloxyethyl phosphorylcholine (MPC) shows excellent performance in resisting nonspecific proteins and bacterial adhesion. In this work, a novel bionic brushes coating containing MPC and N, N, N-trimethyl-2-((4-(2-(4-nonylphenoxy) ethoxy)-4-oxobut-2-enoyl) oxy) ethan-1-aminium chloride (TOEAC), a quaternary ammonium monomer, was prepared onto IOLs using reversible addition–fragmentation chain transfer (RAFT) polymerization method. The P(TOEAC-co-MPC) brushes exhibited excellent antifouling efficiency against bovine serum albumin, Staphylococcus aureus, and human lens epithelial cells. In addition, the P(TOEAC-co-MPC) brushes showed excellent antibacterial and antibiofilm abilities and good biocompatibility. An in vivo study confirmed that the P(TOEAC-co-MPC) brushes effectively prevented PCO and endophthalmitis. Consequently, the P(TOEAC-co-MPC) bionic brushes are promising for IOLs surface modification to resist postoperative complications for long-term implantation.

Combinatorial Ag–Cu thin-films were irradiated by synchrotron X-ray in air to investigate the beam damage on the surface of the thin-film. The main effect was found to be oxidation with the oxidation state primarily depending on film composition: CuO formed on the pure Cu film, whereas Cu2O formed in the presence of Ag. Meanwhile, formation of crystalline Ag2O2 was favored and preferentially in the Ag-rich area. These results are of great importance in studying the oxidation of noble metal nano-film, and in the characterization of nano-films using synchrotron X-ray.

A selective and ratiometric turn-on fluorescent probe was designed and synthesized by using a novel dicyanoisophorone-based derivative and acrylate moiety. The probe displayed high stability and good selectivity to cysteine (Cys) over homocysteine (Hcy) and glutathione (GSH). It also exhibited rapid response to Cys within 180 s. Most importantly, the fluorescence intensity ratio at 590 and 525 nm (I590/I525) was linearly dependent on the Cys concentration in the range from 0 to 40 μM and the detection limit calculated to be 0.48 μM. This probe was also applied for bioimaging of intracellular Cys in living HeLa cells with low cytotoxicity.