A sensor with a red‐emission signal is successfully obtained by the solvothermal reaction of Eu3+ and heterofunctional ligand bpydbH2 (4,4′‐(4,4′‐bipyridine‐2,6‐diyl) dibenzoic acid), followed by ...terminal‐ligand exchange in a single‐crystal‐to‐single‐crystal transformation. As a result of treatments both before and after the metal–organic framework formation, accessible Lewis‐base sites and coordinated water molecules are successfully anchored onto the host material, and they act as signal transmission media for the recognition of analytes at the molecular level. This is the first reported sensor based on a metal–organic framework (MOF) with multi‐responsive optical sensing properties. It is capable of sensing small organic molecules and inorganic ions, and unprecedentedly it can discriminate among the homologues and isomers of aliphatic alcohols as well as detect highly explosive 2,4,6‐trinitrophenol (TNP) in water or in the vapor phase. This work highlights the practical application of luminescent MOFs as sensors, and it paves the way toward other multi‐responsive sensors by demonstrating the incorporation of various functional groups into a single framework.
Multi‐responsive fluorescent sensing is achieved using a Eu metal–organic framework (EuMOF). Accessible Lewis‐base sites and coordinated water molecules are successfully anchored on the EuMOF‐based sensor for the recognition of different analytes at the molecular level. This strategy paves the way for the practical application of luminescent MOF sensors in pollutant‐detection.
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A series of lanthanide metal‐organic frameworks (Ln‐MOFs) are synthesized through solvothermal conditions with 1,3‐bis(4‐carboxyphenyl)imidazolium (H2L). Owing to the lanthanide contraction effect, ...two different types of Ln‐MOFs, namely, {Ln(L)2(OH)·3H2O}n (Ln:Pr, Nd, Sm) and {Ln(L)2(COO)(H2O)2·H2O}n (Ln: Eu, Gd, Tb, Dy, Tm, Yb, Y), and their corresponding codoped Ln‐MOFs EuxTb1‐xL are obtained. With careful adjustment of the relative concentration of the lanthanide ions and the excitation wavelength, the color of the luminescence can be systematically modulated and white light emission can be further successfully achieved. Furthermore, by virtue of the temperature‐dependent luminescent behavior, Eu0.2Tb0.8L allows for the design of a thermometer with an excellent linear response to temperature over a wide range, from 40 to 300 K. This work highlights the practical applications of Ln‐MOFs for tailoring fluorescent color and even obtaining practical white light emission, and especially for sensing temperature as luminescent thermometers in a single framework by controlling in different ways.
Codoped Ln‐metal‐organic frameworks EuxTb1‐xL are synthesized based on the isostructural Ln‐metal‐organic frameworks using lanthanide ion emitters. With careful adjustment of the relative concentration of the lanthanide ions and the excitation wavelength, the emission trajectory can be modulated, allowing white emission. Furthermore, Eu0.2Tb0.8L allows for the design of a thermometer operating over a wide range, from 40 to 300 K.
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In this review, we have taken into consideration of the most recent progress and presented comprehensive investigation, discussion and challenges of rational design MOF-supported or derived ...heterogeneous catalysts for electrocatalysis, organocatalysis, photocatalysis.
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•MOFs can decompose to nanocomposites for heterogeneous catalysis via calcination.•The advantages of MOF-derived nanomaterials can improve catalysis activities.•MOFs can use as excellent supports for catalytic active species.
Metal-organic frameworks (MOFs), as novel developing porous crystalline materials, are promising candidates in the field of heterogeneous catalysis because of their high surface area, diverse structures, low densities, adjusted pore sizes, etc. Recently, increasing attention has focused on developing MOF-supported/derived materials as heterogeneous catalysts. In this review, we present the recent development of MOFs as supports or precursors in the preparation of various functional nanomaterials for heterogeneous catalytic reactions including electrocatalysis, organocatalysis, and photocatalysis. Here, we present a comprehensive discussion on the recent progress and the rational design of MOF-supported or derived heterogeneous catalysts to provide insights into the future development of novel and highly efficient heterogeneous catalysts.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Transition metal‐catalyzed enantioselective C−H activation of prochiral sulfoximines for non‐annulated products remains a formidable challenge. We herein report iridium‐catalyzed enantioselective C−H ...borylation of N‐silyl diaryl sulfoximines using a well‐designed chiral bidentate boryl ligand with a bulky side arm. This method is capable of accommodating a broad range of substrates under mild reaction conditions, affording a vast array of chiral sulfoximines with high enantioselectivities. We also demonstrated the synthetic utility on a preparative‐scale C−H borylation for diverse downstream transformations, including the synthesis of chiral version of bioactive molecules. Computational studies showed that the bulky side arm of the ligand confers high regio‐ and enantioselectivity through steric effect.
A rational‐designed chiral bidentate boryl ligand (CBL) with a bulky side arm was effective in iridium‐catalyzed regio‐and enantioselective C−H borylation of N‐silyl diaryl sulfoximines, affording a vast array of non‐annulated chiral diaryl sulfoximines (39 examples) with high enantioselectivities (up to 96 %). DFT calculations revealed that the side arm was critical to confer high regio‐ and enantioselectivity by virtue of the steric effect.
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Crystalline porous materials are currently a hot research topic in the field of proton-conducting materials. Crystalline porous materials include metal-organic frameworks (MOFs), coordination ...polymers (CPs), polyoxometalates (POMs) and covalent organic frameworks (COFs). The designable structures and high surface areas of these materials provide great opportunities to orderly accommodate proton carriers and to systemically modify the concentration and mobility of proton carriers in available spaces. Based on the understanding of the relationship between the structure and proton conductivity, controllable synthesis of porous materials with high proton conductivity will gradually be achieved. This review summarizes the emerging studies of these materials and their unique proton conductivities.
This review summarizes the emerging studies of proton-conducting materials, and discusses the synthetic strategies and possible mechanisms, identifying key structural factors.
Mercury(II) ions have emerged as a widespread environmental hazard in recent decades. Despite different kinds of detection methods reported to sense Hg2+, it still remains a challenging task to ...develop new sensing molecules to replenish the fluorescence‐based apparatus for Hg2+ detection. This communication demonstrates a novel fluorescent sensor using UiO‐66‐NH2 and a T‐rich FAM‐labeled ssDNA as a hybrid system to detect Hg2+ sensitively and selectively. To the best of our knowledge, it has rarely been reported that a MOF is utilized as the biosensing platform for Hg2+ assay.
Sensing mercury: A novel fluorescent sensor using UiO‐66‐NH2 and a T‐rich FAM‐labeled ssDNA as a hybrid system to detect Hg2+ with a high sensitivity and selectivity has been fabricated successfully (see scheme). It is potentially state of the art research to apply a MOF in a biosensor system to detect Hg2+, opening a broad new world of applications for MOFs.
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Metal–organic frameworks (MOFs) with tunable compositions and morphologies are recognized as efficient self‐sacrificial templates to achieve function‐oriented nanostructured materials. Moreover, it ...is urgently needed to develop highly efficient noble metal‐free oxygen evolution reaction (OER) electrocatalysts to accelerate the development of overall water splitting green energy conversion systems. Herein, a facile and cost‐efficient strategy to synthesize Co9S8 nanoparticles‐embedded N/S‐codoped carbon nanofibers (Co9S8/NSCNFs) as highly active OER catalyst is developed. The hybrid precursor of core–shell ZIF‐wrapped CdS nanowires is first prepared and then leads to the formation of uniformly dispersed Co9S8/N, S‐codoped carbon nanocomposites through a one‐step calcination reaction. The optimal Co9S8/NSCNFs‐850 is demonstrated to possess excellent electrocatalytic performance for OER in 1.0 m KOH solution, affording a low overpotential of 302 mV to reach the current density of 10 mA cm−2, a small Tafel slope of 54 mV dec−1, and superior long‐term stability for 1000 cyclic voltammetry cycles. The favorable results raise a concept of exploring more MOF‐based nanohybrids as precursors to induce the synthesis of novel porous nanomaterials as non‐noble‐metal electrocatalysts for sustainable energy conversion.
Through a one‐step direct pyrolysis process, Co9S8 nanoparticles‐embedded N/S‐codoped carbon nanofibers derived from the hybrid precursor of core–shell ZIF‐wrapped CdS nanowires are successfully achieved which exhibit excellent oxygen evolution reaction catalytic performance. This presented strategy paves the way for exploring more metal–organic framework‐based nanohybrids as precursors to induce the synthesis of novel functional nanomaterials.
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In this review, we present a comprehensive summary of the design strategies and synthetic methods of charged MOFs. Then, we discuss how guest ion exchange can enhance the performance of charged MOFs ...for gas adsorption and separation, luminescence, sensing, pollutants removal, heterogeneous catalysis and proton conduction.
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•Charged MOFs exhibit strong charge-induced interactions.•Charged MOFs can incorporate functional ionic species by ion exchange.•Charged MOFs can realize the selectivity in gas capture and pollutants removal.
As one unique subclass of metal organic frameworks (MOFs), charged MOFs (anionic and cationic MOFs) have attracted extensive attention owing to the strong electrostatic interactions of their charged frameworks. They can serve as interesting cation/anion exchange materials through the exchange of positive/negative counterions in the framework with functional guest species like luminescent or catalytic guest molecules to endow with enhanced performance or unique functions. The inherent charged properties of charged MOFs afford them excellent selectivity in adsorption and separation. This review focuses on the state-of-the-art development of charged MOFs. Firstly, a comprehensive summary of the design strategies and synthetic methods of charged MOFs will be presented. Then, we will discuss how guest ion exchange can enhance the performance of charged MOFs and canvass the potential applications in the fields of gas adsorption and separation, luminescence, sensing, pollutants removal, heterogeneous catalysis and proton conduction. Finally, the critical challenges and future perspectives in this promising field are also highlighted.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Background: Ovarian cancer (OC) is the gynecologic malignant tumor with high mortality. Accumulating evidence indicates that M2-like tumor-associated macrophages (TAMs) can secret EGF to participate ...in ovarian cancer growth, migration, and metastasis. An EGF-downregulated lncRNA, LIMT (lncRNA inhibiting metastasis), was identified as a critical regulator of mammary cell migration and invasion. Nevertheless, whether EGF secreted from M2-like TAMs regulates LIMT expression in ovarian cancer progression remains largely unknown.
Methods: The human OC cell lines OV90 and OVCA429 were recruited in this study. The differentiation of the human monocyte cell line THP-1 into M2-like TAMs was confirmed using flow cytometry within the application of phorbol 12-myristate 13-acetate (PMA). ELISA was performed to detect EGF concentration in co-culture system of M2-like TAMs and OC cell lines. Moreover, CCK-8, flow cytometry and immunofluorescence staining of Ki67 were performed to assess the capacity of cell proliferation. Besides, cell migration and invasion were determined by wound healing and transwell assays. Furthermore, the expression levels of epithelial-mesenchymal transition (EMT) markers and EGFR/ERK signals were analyzed by qRT-PCR and western blot. Female athymic nude mice (8-12 weeks of age; n = 8 for each group) were recruited for in vivo study.
Results: In the present study, THP-1 cells exhibited the phenotype markers of M2-like TAMs with low proportion of CD14
+
marker and high proportion of CD68
+
, CD204
+
, CD206
+
markers within the application of PMA. After co-culturing with M2-like TAMs, EGF concentration in the supernatants was significantly increased in a time-dependent manner. Besides, OC cells presented better cell viability, higher cell proliferation, and stronger migration and invasion. The expression of EMT-related markers N-cadherin, Vimentin and EGFR/ERK signals were markedly up-regulated, while E-cadherin was significantly decreased. However, these effects induced by co-culture system were reversed by the application of AG1478 (an EGFR inhibitor) or LIMT overexpression. Furthermore, the endogenous expression of LIMT was decreased in OC cell lines compared with the control group. Also, the in vivo experiments verified that the inhibition of EGFR signaling by AG1478 or overexpression of LIMT effectively repressed the tumor growth.
Conclusion: Taken together, we demonstrated that EGF secreted by M2-like TAMs might suppress LIMT expression via activating EGFR-ERK signaling pathway to promote the progression of OC.
We studied the value of circulating tumor DNA (ctDNA) in predicting early postoperative tumor recurrence and monitoring tumor burden in patients with hepatocellular carcinoma (HCC). Plasma‐free DNA, ...germline DNA, and tissue DNA were isolated from 41 patients with HCC. Serial ctDNAs were analyzed by next‐generation sequencing before and after operation. Whole‐exome sequencing was used to detect the DNA of HCC and adjacent tissues. In total, 47 gene mutations were identified in the ctDNA of the 41 patients analyzed before surgery. ctDNA was detected in 63.4% and 46% of the patient plasma pre‐ and postoperation, respectively. The preoperative ctDNA positivity rate was significantly lower in the nonrecurrence group than in the recurrence group. With a median follow‐up of 17.7 months, nine patients (22%) experienced tumor recurrence. ctDNA positivity at two time‐points was associated with significantly shorter recurrence‐free survival (RFS). Tumors with NRAS, NEF2L2, and MET mutations had significantly shorter times to recurrence than those without mutations and showed high recurrence prediction performance by machine learning. Multivariate analyses showed that the median variant allele frequency (VAF) of mutations in preoperative ctDNA was a strong independent predictor of RFS. ctDNA is a real‐time monitoring indicator that can accurately reflect tumor burden. The median VAF of baseline ctDNA is a strong independent predictor of RFS in individuals with HCC.
Here, we studied the value of circulating tumor DNA (ctDNA), in combination with germline and tissue DNA by whole‐exome sequencing in patients withhepatocellular carcinoma (HCC). Our analysis demonstrated that ctDNA may serve as a real‐time monitoring indicator by accurately reflecting tumor burden, and as a strong independent predictor of recurrence‐free survival in HCC.
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