Latest ArticlesCalcium dibutyryladenosine cyclophosphate is a widely used cardiovascular drug. The traditional batch synthesis process suffers from long reaction times, tedious operations, and unstable yields. Herein, a sequential continuous flow synthesis combined with a multistage in-line purification process of calcium dibutyryladenosine cyclophosphate was developed. The acylation reaction was completed in a continuous coil reactor at 160 ℃ in 20 min. And the high toxic solvent pyridine was replaced by acetonitrile. Furthermore, the multistage in-line purification process was integrated into the homemade 3D circular cyclone-type micromixer chip. Combining with the membrane phase separators, the residence time of the purification step was 30 s. The isolated yield of this sequential continuous process was 92% with 99% purity.
Functional materials with multiple properties are urgent to be explored to reach high requirements for applications nowadays. In this work, a new multifunctional one-dimensional (1D) chain compound [N(C3H7)4][Cu(ohpma)]·H2O 1 (ohpma = deprotonated N-(2-hydoxyphenyl)oxamic acid) exhibiting both 1D antiferromagnetic and nonlinear optical properties, which are both originated from the same polar [Cu(C8H4NO4)] magnetic units, has been successfully synthesized by evaporation at room temperature. Bis-polydentate nature of the (ohpma)3− ligand with constrained tridentate and bidentate coordination sites conducts Cu2+ ions coordinating in different geometries and forms 1D chains along the c axis, which are further separated by the [N(C3H7)4]+ cations. And the 1D magnetic chains further exhibit noncentrosymmetric polar arrangement. Nonlinear optical study shows polar compound 1 exhibits a discernible second-harmonic generation (SHG) efficiency and the calculation of the partial density of states indicates that the SHG efficiency of 1 is mainly originated from the polar [Cu(C8H4NO4)] magnetic units. Moreover, magnetic susceptibility shows a broad maximum around 70 K with strong intrachain interaction of J/kB = −113.0 K but no long-range order is observed down to 2 K, suggesting that 1 shows a good 1D magnetism. Both good 1D magnetism and SHG activity suggest that 1 could be as a potential multifunctional material, particularly.
The compatibility of the gate dielectrics with semiconductors is vital for constructing efficient conducting channel for high charge transport. However, it is still a highly challenging mission to clearly clarify the relationship between the dielectric layers and the chemical structure of semiconductors, especially vacuum-deposited small molecules. Here, interfacial molecular screening of polyimide (Kapton) dielectric in organic field-effect transistors (OFETs) is comprehensively studied. It is found that the semiconducting small molecules with alkyl side chains prefer to form a high-quality charge transport layer on polyimide (PI) dielectrics compared with the molecules without alkyl side chains. On this basis, the fabricated transistors could reach the mobility of 1.2 cm2 V−1 s−1 the molecule with alkyl side chains on bare PI dielectric. What is more, the compatible semiconductor and dielectric would further produce a low activation energy (EA) of 3.01 meV towards efficient charge transport even at low temperature (e.g., 100 K, 0.9 cm2 V−1 s−1). Our research provides a guiding scheme for the construction of high-performance thin-film field-effect transistors based on PI dielectric layer at room and low temperatures.
In recent years, with the emergence of non-fullerene fused-ring acceptors, power conversion efficiencies (PCEs) of organic solar cells (OSCs) have exceeded 19%. However, compared to inorganic or perovskite photovoltaic cells, a higher voltage loss has become one of the key factors limiting further improvement in the PCEs of OSCs. The ternary/quaternary strategy has been identified as a feasible and effective way to obtain high-efficiency OSCs. In this review, a brief outline is given of the key roles that guest materials played in reducing voltage losses in solar cell devices and a brief look at the future material design and the design of ternary/quaternary systems.
Activated hepatic stellate cells (aHSCs), the main source of extracellular matrix deposition, are key targets in liver fibrosis. However, no effective drug specific to aHSCs has been clinically applied due to poor drug delivery efficiency. Herein, we designed a CXC chemokine receptor 4 (CXCR4)-targeted reactive oxygen species (ROS)-responsive platform AMD-Dex-ROS-responsive-sorafenib (ARS) based on natural polysaccharide and thioctic acid frame, which can deliver anti-fibrosis drug represented by sorafenib specifically to aHSCs on account of CXCR4 over-expression on aHSCs, and smartly disassemble via ROS-responsive thioketal rupture relying on high intracellular ROS in HSCs, realized on-demand drug release and effective liver fibrosis reversion. Notably, in this platform, the CXCR4 antagonist AMD3100 not only enhanced aHSCs targeting efficiency of sorafenib but also effectively magnified the aHSCs elimination of sorafenib by blocking stroma cell derived factor-1 (SDF-1)/CXCR4-induced aHSCs protection, resulting in synergistic anti-fibrosis effect. The platform provided a new approach for drug delivery system design and liver fibrosis treatment.
Membrane permeability and intracellular diffusion of fluorescent probes determine staining selectivity of intracellular substructures. However, the relationship between the molecular structure of fluorescent probes and their membrane permeability and intracellular distribution is poorly understood. In this paper, we reported a series of 1,8-naphthalimide dyes and carried out cell imaging experiments, and found that the presence of amino hydrogen in these dyes played a crucial role in their cell membrane permeability and intracellular distribution. The secondary amino group containing compounds 1–4 show excellent membrane permeability and strong fluorescence in living cells. While the tertiary amine containing dyes 5 and 6 can hardly permeate the cell membrane though they show extremely similar structure with compounds 2–4. Compound 1 can selectively image lipid droplets by selecting the wavelength of excitation light. With the specificity for lysosomes, 2 and 4 have been used in long-term time-lapses imaging of lysosomal dynamics and tracking the process of lysosome–lysosome interaction, fusion and movement. The effect of hydrogen-containing amino substituent on the cell membrane permeability of fluorescent molecules is promising for the development of better biocompatible probes.
Chiroptical switches based on circularly polarized luminescence (CPL) have shown the promising applications in advanced information technologies. Herein, a pair of lanthanide coordination polymer enantiomers [Eu2(LR)3(BTFPO)2]n and [Eu2(LS)3(BTFPO)2]n with light-regulated CPL property are designed, which are assembled by a chiral binuclear triple-stranded Eu3+ helicates [Eu2(LR/S)3] coordinated with two photochromic triphenylphosphine oxides (BTFPO). Upon the alternative UV and 526 nm light irradiation, the complexes show the reversible photochromism, PL and CPL responses. Notably, the luminescence dissymmetry factor, glum of 5D0→7F1 (591 nm) transition shows an obvious increase from 0.19 to 0.29 before and after 275 nm light irradiation. Additionally, the emission from Eu3+ center is not completely quenched in closed-ring state due to the low photocyclization (Фo-c) quantum yield of the polymer. The partial maintenance of emissive intensity is of essential importance for the monitor of CPL signal. More importantly, the CPL photo-switching property of the complexes in solid hybrid film is maintained, and still displays the enhanced CPL emission in photostationary state. Further, the potential applications of the doping film in logic gate and anti-counterfeiting were investigated.
Prostate cancer (PC) biomarker-citrate detection is clinically important to diagnose PC in early stages. Methylquinolinium iodide (Q) conjugated indole-phenylboronic acid (IB) was designed as a red-emissive QIB probe for the detection of citrate through Lewis acid–base reaction and intramolecular charge transfer (ICT) sensing mechanisms. Boronic acid acts as Lewis acid as well as citrate (Lewis base) recognition unit. The probe reacted with citrate, showing enhanced red emissions. Since the probe has excellent water solubility and great biocompatibility, practical application in biological systems is possible. Citrate was monitored precisely in the mitochondria organelle (in vitro) of living cells with a positive charge on QIB. Also, endogenous (in situ) citrate was detected quantitatively to discriminate non-cancerous and PC mice, observed strong and lower (negligible) emission intensity on non-cancerous and cancerous prostate tissues, respectively. Because, the concentration of citrate is higher in healthy prostate compared with PC prostate. Furthermore, the analysis of sliced prostate tissues can give PC-related information for clinical diagnosis to prevent and treat PC in the initial stages. Therefore, we believe that the present probe is a promising biochemical reagent in diagnosing PC.
Si-based materials have shown great potential as lithium-ion batteries (LIBs) anodes due to their natural reserves and high theoretical capacity. However, the large volume changes during cycles and poor conductivity of Si lead to rapid capacity decay and poor cycling stability, ultimately limiting their commercial applications. Herein, we have skillfully utilized the microporous MCM-22 zeolite as the unique silicon source to produce porous Si (pSi) sheets by a simple magnesiothermic reduction, followed by a carbon coating and further Ti3C2Tx MXene assembly, obtaining the ternary pSi@NC@TNSs composite. In the design, porous Si sheets provide more active sites and shorten Li-ion transport paths for electrochemical reactions. The N-doped carbon (NC) layer serves as a bonding layer to couple pSi and Ti3C2Tx. The conductive network formed by 2D Ti3C2Tx and medium NC layer effectively enhances the overall charge transport of the electrode material, and helps to stabilize the electrode structure. Therefore, the as-made pSi@NC@TNSs anode delivers an improved lithium storage performance, exhibiting a high reversible capacity of 925 mAh/g at 0.5 A/g after 100 cycles. This present strategy provides an effective way towards high-performance Si-based anodes for LIBs.
The unique properties of metal oxide surfaces, crystal surfaces and defects play vital roles in biomass upgrading reactions. In this work, hierarchical porous bowl-shaped ZrO2 (HB-ZrO2) with mixed crystal phase was designed and employed as the support for loading AuPd bimetal with different proportions to synthesize AuPd/HB-ZrO2 catalysts. The effects of surface chemistry, oxygen defects, bimetal interaction and metal-support interaction of AuPd/HB-ZrO2 on catalytic performance for the selective oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) were systematically investigated. The Au2Pd1/HB-ZrO2 catalyst afforded a satisfactory FDCA yield of 99.9% from HMF oxidation using O2 as the oxidant in water, accompanied with an excellent FDCA productivity at 97.6 mmol g−1 h−1. This work offers fresh insights into rationally designing efficient catalysts with oxygen-rich defects for the catalytic upgrading of biomass platform chemicals.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62662699(Operation and Technical Support)
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
