Hydrogen‐bonded organic frameworks (HOFs) possess various merits, such as high porosity, tunable structure, facile modification, and ready regeneration. These properties have yet to be explored in ...the context of new functional HOF materials. The facile and inexpensive electrophoretic deposition (EPD) method applied in this study generated a transparent HOF film at room temperature in just 2 min and is applicable to other HOFs. The resulting film exhibited reversible electrochromism with the advantage of long cycle life (>500 cycles). More strikingly, this all‐organic film could be readily regenerated (through rinsing with DMF and redeposition) and showed tunable electrochromic behavior (through low‐cost postsynthetic modification) with the ability to undergo successive color changes, which is difficult to achieve with conventional electrochromic materials. An electrochromic device was manufactured to further demonstrate the application potential of the film.
Facile and efficient electrophoretic deposition was used to prepare an electrochromic hydrogen‐bonded organic framework film (see picture), which exhibited reversible electrochromism with the advantages of long cycle life, ready regeneration, and tunable electrochromic behavior. An electrochromic device was manufactured with the film to further demonstrate its application potential.
The galectin family consists of carbohydrate (glycan) binding proteins that are expressed by a wide variety of cells and bind to galactose-containing glycans. Galectins can be located in the nucleus ...or the cytoplasm, or can be secreted into the extracellular space. They can modulate innate and adaptive immune cells by binding to glycans on the surface of immune cells or intracellularly via carbohydrate-dependent or carbohydrate-independent interactions. Galectins expressed by immune cells can also participate in host responses to infection by directly binding to microorganisms or by modulating antimicrobial functions such as autophagy. Here we explore the diverse ways in which galectins have been shown to impact immunity and discuss the opportunities and challenges in the field.
Functionalization of hydrogen‐bonded organic frameworks (HOFs) for specific applications has been a long‐lasting challenge in HOF materials. Here, an efficient way to integrate functional species in ...the HOF structure through constructing an anionic framework is presented. The obtained HOFs, taking PFC‐33 (PFC = porous materials from FJIRSM,CAS) as an example, integrate a porphyrin photosensitizer as a porous backbone and a commercial biocide as counterions in the structure. The permanent channels and the electrostatic interaction between the framework and the counterions provide PFC‐33 ion‐responsive biocide‐release behavior in various physiological environments, thus exhibiting synergistic photodynamic and chemical antimicrobial efficiency. The unbonded carboxyl groups residing on the HOF surface further allow for manipulating the interfacial interaction between the PFC‐33 and the polymer matrix for membrane fabrication. Therefore, a polyHOF membrane with high stability, desired flexibility, and good permeability is obtained, which demonstrates noticeable bacterial inhibition toward Escherichia coli. This study may shed light on the functionalization of HOF materials for broad application potentials.
The functionalization of hydrogen‐bonded organic frameworks (HOFs) can be achieved in a porphyrin‐based anionic HOF structure, endowing the material with synergistic photodynamic and chemical antimicrobial efficacy. By further taking advantage of the unbonded carboxyl groups on the HOF particle surface, a freestanding flexible membrane that shows high permeability, good stability, and excellent antibacterial activity is successfully fabricated.
Ionic liquids (ILs) comprise mostly of organic salts with negligible vapor pressure and low flammability that are proposed as replacements for volatile solvents. ILs have been promoted as “green” ...solvents and widely investigated for their various applications. Although the utility of these chemicals is unquestionable, their toxic effects have attracted great attention. In order to manage their potential hazards and design environmentally benign ILs, understanding their environmental behavior, fate and effects is important. In this review, environmentally relevant issues of ILs, including their environmental application, environmental behavior and toxicity are addressed. In addition, also presented are the influence of ILs on the environmental fate and toxicity of other coexisting contaminants, important routes for designing nontoxic ILs and the techniques that might be adopted for the removal of ILs.
Oxidative stress is commonly involved in the pathogenesis of skin damage induced by environmental factors, such as heat stress. Skin fibroblasts are responsible for the connective tissue regeneration ...and the skin recovery from injury. Aloin, a bioactive compound in Aloe vera, has been reported to have various pharmacological activities, such as anti-inflammatory effects. The aim of this study was to investigate the protective effect of aloin against heat stress-mediated oxidative stress in human skin fibroblast Hs68 cells. Hs68 cells were first incubated at 43°C for 30 min to mimic heat stress. The study was further examined if aloin has any effect on heat stress-induced oxidative stress. We found that aloin protected Hs68 cells against heat stress-induced damage, as assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assay. Aloin protected Hs68 cells by regulating reactive oxygen species production and increasing the levels of glutathione, cytosolic and mitochondrial superoxide dismutase. Aloin also prevented the elevation of thiobarbituric acid reactive substances and the reduction of 8-OH-dG induced by heat stress. These results indicated that aloin protected human skin fibroblasts from heat stress-induced oxidative stress damage by regulating the oxidative defense system.
Aryl-C-glycosides, of both synthetic and natural origin, are of great significance in medicinal chemistry owing to their unique structures and stability towards enzymatic and chemical hydrolysis as ...compared to O-glycosides. They are well-known antibiotics and potent enzyme inhibitors and possess a wide range of biological activities such as anticancer, antioxidant, antiviral, hypoglycemic effects, and so on. Currently, a number of aryl-C-glycoside drugs are on sale for the treatment of diabetes and related complications. This review summarizes the findings on aryl-C-glycoside scaffolds over the past 20 years, concerning new structures (over 200 molecules), their bioactivities—including anticancer, anti-inflammatory, antioxidant, antivirus, glycation inhibitory activities and other pharmacological effects—as well as their synthesis.
It is still a great challenge to achieve high selectivity of CH4 in CO2 electroreduction reactions (CO2RR) because of the similar reduction potentials of possible products and the sluggish kinetics ...for CO2 activation. Stabilizing key reaction intermediates by single type of active sites supported on porous conductive material is crucial to achieve high selectivity for single product such as CH4. Here, Cu2O(111) quantum dots with an average size of 3.5 nm are in situ synthesized on a porous conductive copper‐based metal–organic framework (CuHHTP), exhibiting high selectivity of 73 % towards CH4 with partial current density of 10.8 mA cm−2 at −1.4 V vs. RHE (reversible hydrogen electrode) in CO2RR. Operando infrared spectroscopy and DFT calculations reveal that the key intermediates (such as *CH2O and *OCH3) involved in the pathway of CH4 formation are stabilized by the single active Cu2O(111) and hydrogen bonding, thus generating CH4 instead of CO.
Cu2O(111) single‐type sites on a conductive metal–organic framework are successfully prepared by an in situ electrochemical method. The cooperative effect between the single active Cu2O(111) and hydrogen bonding contributes to the high selectivity of 73 % towards CH4 with large current density in CO2 electroreduction reduction for the obtained Cu2O(111)@CuHHTP.
The low structural stability of hydrogen‐bonded organic frameworks (HOFs) is a thorny issue retarding the development of HOFs. A rational design approach is now proposed for construction of a stable ...HOF. The resultant HOF (PFC‐1) exhibits high surface area of 2122 m2 g−1 and excellent chemical stability (intact in concentrated HCl for at least 117 days). A new method of acid‐assisted crystalline redemption is used to readily cure the thermal damage to PFC‐1. With periodic integration of photoactive pyrene in the robust framework, PFC‐1 can efficiently encapsulate Doxorubicin (Doxo) for synergistic chemo‐photodynamic therapy, showing comparable therapeutic efficacy with the commercial Doxo yet considerably lower cytotoxicity. This work demonstrates the notorious stability issue of HOFs can be properly addressed through rational design, paving a way to develop robust HOFs and offering promising application perspectives.
An ultra‐robust hydrogen‐bonded organic framework with high BET surface area and acid‐assisted crystalline recovery was developed through several rational design strategies. With periodic integration of photoactive pyrene in the framework, this material can efficiently encapsulate the drug doxorubicin for synergistic chemo‐photodynamic therapy, showing low cytotoxicity and prominent therapeutic efficacy.
Precise control of solid-state elastic waves' mode content and coherence is of great use nowadays in reinforcing mechanical energy harvesting/storage, nondestructive material testing, wave-matter ...interaction, high sensitivity sensing, and information processing, etc. Its efficacy is highly dependent on having elastic transmission channels with lower loss and higher degree of freedom. Here, we demonstrate experimentally an elastic analog of the quantum spin Hall effects in a monolithically scalable configuration, which opens up a route in manipulating elastic waves represented by elastic pseudospins with spin-momentum locking. Their unique features including robustness and negligible propagation loss may enhance elastic planar-integrated circuit-level and system-level performance. Our approach promotes topological materials that can interact with solid-state phonons in both static and time-dependent regimes. It thus can be immediately applied to multifarious chip-scale topological phononic devices, such as path-arbitrary elastic wave-guiding, elastic splitters and elastic resonators with high-quality factors.
The reaction of ferrous salts and square‐planar tetracyanometallates MII(CN)42− (M=Pd, Pt) with ligand 4‐(1H‐pyrazol‐3‐yl)pyridine (Hppy) resulted in the formation of two two‐dimensional (2D) ...Hofmann‐like coordination polymers (CPs) with the general formula of {FeII(Hppy)2MII(CN)4}⋅H2O (M=Pd for 1Pd, Pt for 1Pt). The two CPs have been studied by variable‐temperature single‐crystal X‐ray crystallography, differential scanning calorimetry, and magnetic measurements. Polymers 1Pd and 1Pt are isostructures, in which the FeII atoms are equatorially coordinated with MII(CN)42− to form 2D undulating layers and axially coordinated with Hppy ligands. Both compounds undergo cooperative, complete spin crossover (SCO), with characteristic abrupt and remarkable two equal steps, featuring hysteresis widths of 14 K and 19 K (1Pd) and 17 and 23 K (1Pt) for the two steps. The SCO cooperativity may result from the hydrogen bonds and π⋅⋅⋅π interactions within and between such 2D layers, and the two‐step SCO behavior is accompanied with phase transitions.
Two Hofmann‐like 2D coordination polymers based on the Hppy ligand (4‐(1H‐pyrazol‐3‐yl)pyridine) have been synthesized and characterized. The polymers exhibit cooperative spin crossover with abrupt and two‐step behaviors accompanied by a symmetry‐breaking structural phase transition.
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