Latest ArticlesCell migration proceeds in 3D matrices in vivo, which can naturally switch to distinct phenotypes for better invasion in confined microenvironments. The studies of important metabolites under confinement are extremely meaningful for comprehensive insights into cancer metastasis. The integration of cell confinement device and analytical techniques is a key point for in-situ analysis of significant metabolites in vitro. Herein, an electrochemiluminescence (ECL) sensing platform was designed for in-situ monitoring of cell-secreted lactate in highly confined microenvironments. The 3-µm confiner was exactly fabricated via microfabrication and microfluidics technique, and cells in high confinement and low adhesion tended to be round with contractile blebs on cell margins. Significantly, in-situ monitoring of lactate was successfully achieved on the ECL platform with the catalysis of lactate oxidase, in which the levels in different time intervals were acquired in the luminol-hydrogen peroxide system. Furthermore, the results were verified by the liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology, which showed similar fluctuations with the ECL platform. This system offered an available avenue for metabolites analysis in highly confined microenvironments, which may advance deeper insights into metabolic mechanisms of cancer metastasis
Two-dimensional (2D) materials composed of single pnictogen element, namely, 2D pnictogens (e.g., black phosphorus, arsenene, antimonene and bismuthine), have recently showed remarkable potential for biomedical applications, especially after the rapid development of black phosphorus. With unique optical and electronic properties, 2D pnictogens are considered as promising nanoagents for biosensors, diagnosis and therapy. In this review, after brief introduction of the structure, properties, synthesis strategies, and biocompatibility of 2D pnictogens, their biomedical applications including anti-tumor, anti-inflammation, anti-bacterial, neurodegenerative treatment and tissue repairing are reviewed. The major obstacles and opportunities of 2D pnictogens are also discussed. This review provides a short yet timely summary on the synthesis and biomedical applications of emerging 2D pnictogens.
Glutathione (GSH) is a key maintainer of cellular redox balance and plays an important role in many physiological effects. For example, GSH has been widely implicated in cancer initiation, progression and metastasis. Moreover, the concentrations of GSH in tumor cells can influence drug resistance. Given the serious harmfulness of cancer and the important roles of GSH in cancer, it has great significance to development probes for screening of tumor cells and real-time monitoring of GSH fluctuations in tumor cells. However, no targetable probe for reversible imaging of GSH in tumor cells has been reported. Herein, we constructed a melatonin-based targetable and reversible fluorescent probe (GR-MT) for screening of tumor cells and real-time imaging of GSH fluctuations in tumor cells. The probe uses coumarin as the skeleton, Michael addition reaction as the reaction mechanism, and melatonin as the targeted groups of tumor cells. The experimental results demonstrate this probe has many advantages including high selectivity, satisfactory sensitivity, excellent reversible ability, rapid reaction speed, and outstanding targetability of tumor cells. Therefore, this study provides a promising tool for tumor cells screening and real-time detection of GSH fluctuations in specific tumor cells.
Single metal atoms immobilized on a carbon substrate are of great potential for enhancing the catalytic activities for oxygen reduction and methanol oxidation reactions (ORR/MOR) owing to the maximized atom utilization. Herein, single copper atoms (SCAs) are loaded on macro-porous nitrogen-doped carbon (Cu-NC) derived from zeolitic imidazolate framework-8 (ZIF-8), which are used as catalysts for ORR and Pt-supports for MOR. For ORR, the catalyst marked as Cu-NC-3 exhibits a higher peak potential of 0.87 V (vs. Reversible hydrogen electrode) than that of commercial Pt/C (0.83 V), mainly attributing to that the 3D macro-porous structure of Cu-NC-3 provides adequate space for uniform dispersion of SCAs as the main active species, and smooth diffusion pathways for fast transport of substances (O2, H2O), therefore reducing the overpotential and the intermediate (H2O2) generation to enhance ORR activity. For MOR, Pt-Cu-NC-3 has a higher mass activity of 1217.4 mA/mgPt than that of Pt/C (752.4 mA/mgPt), and its activity maintenance (decline of 27.6%) is also better than Pt/C (decline of 44.0%) after 5000 cyclic voltammetry (CV) cycles. The interactions between SCAs and Pt nanoparticles should facilitate the generation of OH- from water molecules, which can fast eliminate the adsorbed CO to recover the Pt active sites to improve MOR performance. This synthesis strategy affords a new inspiration to prepare single metal atoms loaded on ZIFs-derived macro-structure with diverse activities for ORR/MOR.
Low-valence transition metallic complexes have drawn longstanding attention due to their high reactivity toward catalytic transformation of various small molecules. Among these known complexes, the low-valence metal centres are commonly stabilized by neutral bulky ligands with strong electron-donating capacity. However, low-valence bimetallic complexes supported by anionic sulfur and cyclopentadienyl ligands are still difficult to obtain in high isolated yield. Herein, we report the synthesis and characterization of two scarce thiolate-bridged CoⅠCoⅡ and CoⅠCoⅠ complexes bearing sterically demanding ligands through two stepwise one-electron reduction processes. Interestingly, the CoⅠCoⅡ complex can facilely promote the homolytic cleavage of dihydrogen across the short Co−Co metallic bond to give a CoⅡCoⅢ dihydride bridged complex, which is capable of serving as a competent hydrogen atom transfer agent. Moreover, the anionic CoⅠCoⅠ complex can trigger a stepwise hydrogen generation cycle involving several isolated and structurally well-characterized intermediates.
We report the convenient synthesis of a benzobis(imidazolium)-embedded conjugated polyelectrolyte pBBI by a Cu-catalyzed direct C‒H arylation of a cationic benzobis(imidazolium) monomer with a diiodide comonomer. pBBI shows weak fluorescence in solution due to rotation of the repeat units in the conjugated backbone, and enhanced fluorescence when electrostatically interacting with a variety of anions to form aggregates. Specially, pBBI responds to the bisulfite anion with intensified unique deep-blue fluorescence easily discriminated by naked eye.
Injectable filling material is a simple and efficient method for soft tissues reconstruction and is extremely popular in not only plastic surgery but also cosmetic industry. However, there is a lack of soft tissue fillers with perfect performance on the market currently. Here, we constructed a new microsphere/hydrogel composite and evaluated its potential as a candidate for soft tissue augmentation. mPEG-PDLLA microspheres were prepared by utilizing a SPG membrane emulsifier which endowed microspheres with good sphericity and particle size uniformity. PDLLA-PEG-PDLLA hydrogel which shared the same component with the mPEG-PDLLA copolymer acted as a carrier and fixed the microspheres at the injected sites. The mPEG-PDLLA microsphere/PDLLA-PEG-PDLLA hydrogel composite was flowable in room temperature and transformed into gel after being heated to body temperature. This feature is convenient for subcutaneous filling. In vivo assessment on mice showed good safety profile of the composite. Moreover, the density of collagen fibers increased over 13 weeks. Overall, this biocompatible microsphere/hydrogel composite involves simple component and no extra crosslinking agents, and has the ability to stimulate collagen production, thus, may be a candidate for soft tissue augmentation.
A copper-catalyzed three-component reaction of alkenes, cycloketone oximes and DABCO·(SO2)2 is developed, which provides a convenient route for the synthesis of diverse (E)-cyanoalkylsulfonyl alkenes in moderate to good yields with excellent regio- and stereoselectivity. A broad substrate scope with excellent functional group tolerance is observed. A plausible radical pathway is proposed, which involves copper-catalyzed ring-opening CC bond cleavage of O-acyl oxime and insertion of sulfur dioxide. During the reaction process, cyanoalkyl radical and cyanoalkylsulfonyl radical are the key intermediates.
Developing phosphors with long-lifetime (millisecond scale or even longer) solid state room temperature phosphorescence (RTP) feature has attracted considerable attention. However, to date, stimuli-responsive phosphors with RTP nature are still rare due to the absence of effective guidelines for the exploitation of luminophors synchronously possessing stimuli-responsive and RTP characteristics. In this work, a series of mononuclear gold(I) complexes are reported. All these complexes exhibit various solid-state RTP properties, and phosphor 1-Cl exhibits long-lived RTP behavior. The effect of halogen atoms on the RTP nature of these complexes is investigated in detail. Furthermore, the introduction of different types of halogen atoms can effectively regulate the phosphorescent mechanochromism phenomena of these gold(I)-containing complexes. In addition, these phosphors display typical aggregation-induced emission (AIE) effect except for phosphor 5-CCl, which lacks hydrogen-bonding interactions compared with the other four phosphors. This work will be very helpful to the development of mechanical-force-responsive AIE phosphors with lasting RTP.
By combining 5, 10, 15, 20-tetra(4-chlorine)phenylporphyrin (TClPP) and α-Keggin polyoxometalate H5PV2Mo10O40 (H5PVMo) via a simple ion-exchange method, an organic-inorganic hybrid material [C44H28N4Cl4]1.5[H2PMo10V2O40]·2C2H6O (H2TClPP-H2PVMo) was prepared and thoroughly characterized by a variety of techniques. The homogeneous photocatalytic degradation of 2-chloroethyl ethyl sulfide (CEES) (5 µL) by H2TClPP-H2PVMo (1 × 10−6 mol/L) was studied in methanol and methanol-water mixed solvent (v/v = 1:1), in which the degradation rate of CEES reached 99.52% and 99.14%, respectively. The reaction followed first-order reaction kinetics, and the half-life and kinetic constant in methanol and the mixed solvent were respectively 33.0 min, −0.021 min−1 and 15.7 min, −0.043 min−1. Mechanism analysis indicated that under visible light irradiation in the air, CEES was degraded via oxidation and alcoholysis/hydrolysis in methanol and the mixed solvent. O2·− and 1O2 generated by H2TClPP-H2PVMo selectively oxidized CEES into a nontoxic sulfoxide. Singlet oxygen capture experiments showed that H2TClPP-H2PVMo (ϕ = 0.73) had a higher quantum yield of singlet oxygen than TClPP (ϕ = 0.35) under an air atmosphere and visible light irradiation.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
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
