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Metal-organic frameworks (MOFs) and MOF-based composites as luminescent sensors with excellent economic practicability and handy operability have attracted much attention. Herein, we designed and fabricated a porous Zn-based MOF, [Zn(OBA)2(L1)·2DMA] n [1; H2OBA = 4,4'-oxybis(benzoic acid), L1 = 2,4,6-tris(4-pyridyl)pyridine, and DMA = N,N-dimethylacetamide], with mixed nodes under solvothermal conditions, and the pore size of 5.9 Å was calculated from N2 adsorption isotherms by using a density functional theory model. The as-synthesized compound 1 is stable in different boiling organic solvents and water solutions with a wide pH range of 2-12 and exhibits intense luminescence emission at 360 nm under excitation of 290 nm. Significantly, compound 1 shows high selective detection of Fe3+, CrO42-, and Cr2O72- in aqueous solution even under the interference of other ions. Compound 1 can quickly sense these ions in a short time and has a striking sensitivity toward Fe3+ with an ultralow limit of detection (LOD) of 1.06 μM. The relatively low LODs for CrO42- and Cr2O72- are 3.87 and 2.37 μM, respectively, compared to the reported works. Meanwhile, compound 1 can be reused to detect Fe3+, CrO42-, and Cr2O72- six times by simple regeneration. Considering the practicability, a mixed-matrix membrane (MMM) incorporated compound 1 and poly(methyl methacrylate) has been constructed. This MMM displays quick detection of Fe3+, CrO42-, and Cr2O72- and prompt regeneration by lifting from the analyte. [https://www.selleckchem.com/products/gsk1120212-jtp-74057.html learn more] This useful MMM shows a comparable LOD below 4.35 μM for these ions. This work presents a cost-effective Zn-based MOF as a functional platform for simple but useful sensing of Fe3+, CrO42-, and Cr2O72- in aqueous solution.A series of ionic uranyl-containing complexes, namely [C2mim]2[UO2(ccnm)4] (1), [C4mim]2[UO2(ccnm)4] (2), [N1111]2[UO2(ccnm)4][H2O]2 (3), and [P2444]2[UO2(dcnm)2(ccnm)2] (4) [(ccnm)- = carbamoylcyanonitrosomethanide; dcnm = dicyanonitrosomethanide; (C2mim)+ = 1-ethyl-3-methylimidazolium; (C4mim)+ = 1-butyl-3-methylimidazolium; (N1111)+ = tetramethylammonium; (P2444)+ = tributyl(ethyl)phosphonium)], were isolated from in situ formed dcnm-based ionic liquids and characterized systematically. It was found that the dcnm anions transformed into ccnm anions during the reactions. These anions coordinate with the uranyl cations in chelate or terminal monodentate coordination mode, affording negative divalent complex anions which can combine with different organic cations and form ionic uranyl-containing complexes. Plenty of C-H···O, N-H···O, C-H···N, N-H···N, and H···H weak interactions are formed in the crystal structures. The transformation of cyano to amide groups contributes to the crystallinity and leads to higher melting points as well as the luminescence quenching of these compounds.Herein, the hydrophobic carboxyl-functionalized ionic liquid (IL-COOH) was encapsulated into the prepared Fe3O4@Zr-MOFs, and the novel water-stable IL-COOH/Fe3O4@Zr-MOF nanocomposites were first synthesized. The polydopamine-functionalized Fe3O4 was introduced to construct the core-shell structure via layer-by-layer modification, and the controlled growth of Zr-MOFs was achieved, which realized the adjustment of charged properties of nanocomposites and simplified the adsorption or extraction process. The IL-COOH/Fe3O4@Zr-MOFs were fully studied by IR, HNMR, XRD, N2 adsorption-desorption isotherms, TEM, EDS mapping, VSM, and so on. Then, they were employed for the selective adsorption and detection of fluoroquinolone antibiotics (FQs). The adsorption isotherms and kinetics demonstrated that the adsorption process followed a pseudo-second-order kinetic model and the Langmuir isotherm model. Among them, IL-COOH/Fe3O4@UiO-67-bpydc showed the best adsorption performance, and the maximum adsorption capacity of ofloxacin was 438.5 mg g-1. Coupled magnetic solid-phase extraction with HPLC-DAD, a convenient, sensitive, and efficient method for extraction and detection of FQs in environmental water, was developed based on IL-COOH/Fe3O4@UiO-67-bpydc. The recoveries of environmental water were ranging from 90.0 to 110.0%, and the detection limits were lower than 0.02 μg L-1. The novel functionalized composites served as solid-phase adsorbents and liquid-phase extractants. This study also provided a promising strategy for designing and preparing multi-functionalized nanocomposites for the removal or detection of pollutants in environmental samples.A combination treatment strategy that relies on the synergetic effects of different therapeutic approaches has been considered to be an effective method for cancer therapy. Herein, a chemotherapeutic drug (doxorubicin, Dox) and a manganese ion (Mn2+) were co-loaded into regenerated silk fibroin-based nanoparticles (NPs), followed by the surface conjugation of phycocyanin (PC) to construct tumor microenvironment-activated nanococktails. The resultant PC-Mn@Dox-NPs showed increased drug release rates by responding to various stimulating factors (acidic pH, hydrogen peroxide (H2O2), and glutathione), revealing that they could efficiently release the payloads (Dox and Mn2+) in tumor cells. The released Dox could not only inhibit the growth of tumor cells but also generated a large amount of H2O2. The elevated H2O2 was decomposed into the highly harmful hydroxyl radicals and oxygen through an Mn2+-mediated Fenton-like reaction. Furthermore, the generated oxygen participated in photodynamic therapy (PDT) and produced abundant singlet oxygen. Our investigations demonstrate that these PC-Mn@Dox-NPs exhibit multiple bioresponsibilities and favorable biosafety. By integrating Dox-induced chemotherapy, Mn2+-mediated chemodynamic therapy, and PC-based PDT via cascade reactions, PC-Mn@Dox-NPs achieved enhanced in vitro and in vivo anticancer efficacies compared to all the mono- or dual-therapeutic approaches. These findings reveal that PC-Mn@Dox-NPs can be exploited as a promising nanococktail for cascade reaction-mediated synergistic cancer treatment.The GABAA receptor is a member of the Cys-loop family and plays a crucial role in the adult mammalian brain inhibition. Although the static structure of this receptor is emerging, the molecular mechanisms underlying its conformational transitions remain elusive. It is known that in the Cys-loop receptors, the interface between extracellular and transmembrane domains plays a key role in transmitting the "activation wave" down to the channel gate in the pore. It has been previously reported that histidine 55 (H55), located centrally at the interfacial β1-β2 loop of the α1 subunit, is important in the receptor activation, but it is unknown which specific gating steps it is affecting. In the present study, we addressed this issue by taking advantage of the state-of-the-art macroscopic and single-channel recordings together with extensive modeling. Considering that H55 is known to affect the local electrostatic landscape and because it is neighbored by two negatively charged aspartates, a well conserved feature in the α subunits, we considered substitution with negative (E) and positive (K) residues. We found that these mutations markedly affected the receptor gating, altering primarily preactivation and desensitization transitions. Importantly, opposite effects were observed for these two mutations strongly suggesting involvement of electrostatic interactions. Single-channel recordings suggested also a minor effect on opening/closing transitions which did not depend on the electric charge of the substituting amino acid. Altogether, we demonstrate that H55 mutations affect primarily preactivation and desensitization most likely by influencing local electrostatic interactions at the receptor interface.3D monolithic reactor has shown great promise for varied heterogeneous catalysis reactions including water treatment, energy generation and storage, and clean fuel production. As a natural porous material, macroporous wood is regarded as an excellent support for inorganic catalyst due to its abundant polar functional groups and channels. On the other hand, a metal organic framework (MOF) has been widely used as heterogeneous catalyst due to its high specific surface area and large amount of microporosities. Combining macroporous wood and a microporous MOF is expected to produce a high-performance 3D reactor and is demonstrated here for Fischer-Tropsch synthesis. The carbonized MOF/wood reactor retains the original cellular structure with over 180 000 channels/cm2. When being decorated with hexagonal-shaped core-shell Co@C nanoparticles aggregates derived from Co-MOF, the MOF/wood reactor resembles a multi-cylinders reactor for Fischer-Tropsch synthesis. Because of the unique combination of macro- and microporous hierarchical structure, the 3D MOF/wood reactor demonstrates exceptional performance under high gas hourly space velocity (81.2% CO conversion and 48.5% C5+ selectivity at 50 L·h-1·gcat-1 GHSV). This validates that MOF/wood can serve as a multi-cylinders and high-power reactor for catalytic reactions, which is expected to be applicable for environmental and energy applications.The combination of area-selective deposition (ASD) with a patternable organic monolayer provides a versatile additive lithography platform, enabling the generation of a variety of nanoscale feature geometries. Stearate hydroxamic acid self-assembled monolayers (SAMs) were patterned with extreme ultraviolet (λ = 13.5 nm) or electron beam irradiation and developed with ASD to achieve line space patterns as small as 50 nm. Density functional theory was employed to aid in the synthesis of hydroxamic acid derivatives with optimized packing density to enhance the imaging contrast and improve dose sensitivity. Near-edge X-ray absorption fine structure spectroscopy and infrared spectroscopy reveal that the imaging mechanism is based on improved deposition inhibition provided by the cross-linking of the SAM to produce a more effective barrier during a subsequent deposition step. With patterned substrates composed of coplanar copper lines and silicon spacers, hydroxamic acids selectively formed monolayers on the metal portions and could undergo a pattern-wise exposure followed by ASD in the first combination of a patternable monolayer with ASD. This material system presents an additional capability compared to traditional ASD approaches that generally reflect a starting patterned surface. Furthermore, this bottoms-up additive approach to lithography may be a viable alternative to subtractive nanoscale feature generation.Cellulose-based materials have gained increasing attention for the development of low-cost, eco-friendly technologies, and more recently, as functional materials in triboelectric nanogenerators (TENGs). However, the low output performance of cellulose-based TENGs severely restricts their versatility and employment in emerging smart building and smart city applications. Here, we report a high output performance of a commercial cellulosic material-based energy harvesting floor (CEHF). Benefiting from the significant difference in the triboelectric properties between weighing and nitrocellulose papers, high surface roughness achieved by a newly developed mechanical exfoliation method, and large overall contact area via a multilayered device structure, the CEHF (25 cm × 15 cm × 1.2 cm) exhibits excellent output performance with a maximum output voltage, current, and power peak values of 360 V, 250 μA, and 5 mW, respectively. It can be directly installed or integrated with regular flooring products to effectively convert human body movements into electricity and shows good durability and stability.