Templated assembly of sulfide nanoclusters into Cubic-C3N4 type framework

通讯作者地址: Feng, PY (通讯作者), Univ Calif Riverside, Dept Chem, Riverside, CA 92521 USA 地址: 1. Univ Calif Riverside, Dept Chem, Riverside, CA 92521 US

Pushing up the size limit of chalcogenide supertetrahedral clusters: Two- and three-dimensional photoluminescent open frameworks from (Cu5In30S54)(13-) clusters

通讯作者地址: Feng, PY (通讯作者), Univ Calif Riverside, Dept Chem, Riverside, CA 92521 USA 地址: 1. Univ Calif Riverside, Dept Chem, Riverside, CA 92521 USA 2. Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 US

Design of Pore Size and Functionality in Pillar-Layered Zn-Triazolate-Dicarboxylate Frameworks and Their High CO₂/CH₄ and C2 Hydrocarbons/CH₄ Selectivity

In the design of new materials, those with rare and exceptional compositional and structural features are often highly valued and sought after. On the other hand, materials with common and more accessible modes can often provide richer and unsurpassed compositional and structural variety that makes them a more suitable platform for systematically probing the composition–structure–property correlation. We focus here on one such class of materials, pillar-layered metal–organic frameworks (MOFs), because different pore size and shape as well as functionality can be controlled and adjusted by using pillars with different geometrical and chemical features. Our approach takes advantage of the readily accessible layered Zn-1,2,4-triazolate motif and diverse dicarboxylate ligands with variable length and functional groups, to prepare seven Zn-triazolate-dicarboxylate pillar-layered MOFs. Six different gases (N₂, H₂, CO₂, C₂H₂, C₂H₄, and CH₄) were used to systematically examine the dependency of gas sorption properties on chemical and geometrical properties of those MOFs as well as their potential applications in gas storage and separation. All of these pillar-layered MOFs show not only remarkable CO₂ uptake capacity, but also high CO₂ over CH₄ and C2 hydrocarbons over CH₄ selectivity. An interesting observation is that the BDC ligand (BDC = benzenedicarboxylate) led to a material with the CO₂ uptake outperforming all other metal-triazolate-dicarboxylate MOFs, even though most of them are decorated with amino groups, generally believed to be a key factor for high CO₂ uptake. Overall, the data show that the exploration of the synergistic effect resulting from combined tuning of functional groups and pore size may be a promising strategy to develop materials with the optimum integration of geometrical and chemical factors for the highest possible gas adsorption capacity and separation performance

Simeprevir restores the anti-Staphylococcus activity of polymyxins

Abstract Methicillin-resistant Staphylococcus aureus (MRSA) infection poses a severe threat to global public health due to its high mortality. Currently, polymyxins are mainly used for the treatment of Gram-negative bacterial-related infection, while exhibiting limited antibacterial activities against Staphylococcus aureus (S. aureus). However, the combination of antibiotics with antibiotic adjuvants is a feasible strategy for the hard-treated infection and toxicity reducing. We will investigate the antibacterial activity of simeprevir (SIM), which treated for genotype 1 and 4 chronic hepatitis C, combined with polymyxins against MRSA through high-throughput screening technology. In our study, the synergistic antibacterial effect of SIM and polymyxins against S. aureus in vitro was found by checkerboard assay and time-growth curve. The cytotoxicity of SIM combined with polymyxin B sulfate [PB(S)] or polymyxin E (PE) in vitro was evaluated using CCK-8, human RBC hemolysis and scratch assays. In addition, we investigated the eradication of biofilm formation of S. aureus by biofilm inhibition assay and the killing of persister cells. Moreover, we evaluated the therapeutic effect and in vivo toxicity of the combination against MRSA in murine subcutaneous abscess model. Furthermore, it was preliminarily found that SIM significantly enhanced the destruction of MRSA membrane by SYTOX Green and DISC3(5) probes. In summary, these results reveal that the therapy of SIM combined with polymyxins (especially PE) is promising for the treatment of MRSA infection

Improving Photoluminescence Emission Efficiency of Nanocluster-Based Materials by in Situ Doping Synthetic Strategy

Solid-state red phosphors of Mn²⁺-doped nanocrystals usually suffer from poor intensity. While the d–d emission of Mn²⁺ in yellow window has been extensively studied, shift toward lower energy remains challenging. Typically, intrinsic surface defects and self-purification of dopants are two obstacles for enhancing the intensity of red emission. Moreover, for red phosphors Mn²⁺ ions also need an appropriate host matrix and environment. Through an in situ doping strategy and optimization of the Mn²⁺ doping level, intense red-emitting Mn²⁺ dopant emission is reported here for MnCdInS@InS host. The doping strategy allows doping of Mn²⁺ at the core and/or surface sites of supertetrahedral “core–shell” nanocluster (Mn@MnCdInS@InS), leading to the red emission (at 643 nm) with over 40% quantum yield. Moreover, systematic control of doping level results in a series of crystalline Mn²⁺-doped materials with tunable photoluminescence quantum yield. In addition to the synthesis of an important class of red-emitting materials rarely obtained from Mn²⁺ doping, details of the physical chemistry associated with the doping process are probed with the new fundamental findings reported here