Latest ArticlesIn the fight against bacterial infections, it is critical to effectively disrupt biofilms. However, disruption of biofilms becomes exceptionally difficult due to the low permeability of therapeutic agents. Herein, we present a self-propelled nanovesicle (PCL-PLG@CHX) strategy for eliminating biofilms and further expediting the healing of wounds. PCL-PLG@CHX is synthesized by assembling vesicles from amphiphilic polymers, which incorporate both poly-ε-caprolactone and guanidinated-poly-ε-lysine (PCL-PLG) and are infused with chlorhexidine (CHX). Upon application to sites of bacterial infection, PCL-PLG@CHX, abundant in guanidinium structures, effectively accumulates on the negatively charged surface of biofilms. It interacts with reactive oxygen species (ROS) within the biofilm, leading to nitric oxide (NO) production. The generated NO cannot only propel the nanovesicle to penetrate deeper into the biofilm, but also act as a signaling molecule to disperse the biofilm, working in conjunction with the subsequent release of CHX for an enhanced antibacterial impact. Following the eradication of bacteria, the residual guanidine component continues to produce small quantities of NO, facilitating angiogenesis and epithelial growth, thereby accelerating the healing of wounds. Together, our study shows that PCL-PLG@CHX utilizes the potential of guanidine moieties to efficiently break down biofilms and support tissue restoration, tackling the pivotal challenge of biofilm-related diseases.
Invasive fibroblast-like synoviocytes (FLS), inflammatory macrophages and osteoclasts are the main three contributors to rheumatoid arthritis (RA) progression by promoting synovial inflammation and destructing cartilage and bone. Targeting these three cell types for restoring the inflammatory homeostasis microenvironment may be a promising anti-RA strategy. Herein, we prepared a reactive oxygen species (ROS)-responsive micelles (DPTM) to co-load dexamethasone (DEX) and pristimerin (PRI) for RA therapy. This ROS-responsive system exhibits the following advantages: (1) It makes use of the "ELVIS" effect for passive delivery and targeting the ROS environment of RA-related cells to rapidly release the payload drugs DEX and PRI. (2) Compared with free drugs, DPTM showed stronger effect on the inhibition of RA-FLS proliferation and the promotion of RA-FLS apoptosis. Moreover, DPTM could significantly weaken the migration ability of RA-FLS as indicated by the results of wound healing assay and transwell assay. (3) DPTM exerted stronger cellular uptake and anti-inflammatory effect in M1 macrophages. (4) In the model studying receptor activator of nuclear factor kappa-B ligand (RANKL)-induced differentiation of bone marrow-derived macrophages (BMDMs) to osteoclasts, DPTM showed a stronger inhibitory activity on osteoclast formation as compared to free drugs. Taken together, these results highlighted the potential of DPTM for targeted RA therapy via inhibition of RA-FLS abnormal activation, macrophage polarization and osteoclastogenesis.
Intracellular bacteria (ICB), cloaked by the protective barriers of host cells, pose a formidable challenge to selective and efficient eradication. The employment of activatable photosensitizers based antibacterial photodynamic therapy (aPDT) holds significant potential for selective imaging and photo-inactivation of ICB while minimizing side effects on normal cells. Drawing inspiration from the elevated hypochlorous acid (HClO) levels in ICB infected phagocytes, herein we firstly designed and synthesized a series of HClO-responsive dinuclear Ru(Ⅱ) complexes (Ru1-Ru3) to achieve such a goal. Initially, the luminescence, 1O2 generation and aPDT activity of these Ru(Ⅱ) complexes were suppressed due to the quenching effect of the azo group, but were recovered after reaction with HClO in solutions or within ICB infected phagocytes. The detailed results revealed that Ru1 and Ru3 could not only selectively visualize ICB, but also demonstrated remarkable aPDT activity against ICB, surpassing vancomycin both in vitro and in vivo.
Photoredox-mediated reversible-deactivation radical polymerization (RDRP) is an effective approach to synthesize polymers with defined composition and architecture. Current photoinduced RDRP primarily depends on outer-sphere electron transfer or homolysis mechanisms. Herein, we describe an example of iodine-mediated RDRP facilitated by photoinduced charge transfer complex (CTC) catalysis. The approach uses cheap and easily accessible N-heterocyclic nitrenium salt (NHN+···I-) as the photoactive CTC. Upon the irradiation of visible light, NHN+···I- undergoes single electron transfer to generate NHN• and I• radicals. The NHN• radical activates dormant Pn-I polymers via inner-sphere single electron transfer, leading to the propagating Pn• radical for chain growth and the I- anion for recovering the CTC, and the I• radical deactivates the polymerization via coupling with Pn•.
Pure organic materials with ultralong room-temperature phosphorescence (RTP) and persistent luminescence in broad color gamut exhibit tremendous potential and broad application prospects due to their unique optical properties. This article proposes a simple strategy, polyatomic synergistic effect, to endow persistent luminescent materials with ultralong lifetime and broad color-tunability through polyatomic synergistic effect and non-traditional phosphorescence resonance energy transfer (PRET). By leveraging the polyatomic synergistic effect to enhance the intersystem crossing (ISC) in bibenzimidazole (BBI) derivatives and suppress the non-radiative transition process, ultralong persistent room-temperature phosphorescence has been successfully achieved after incorporating BBI-Cl-M into poly(methyl methacrylate) (PMMA) to form a rigid matrix(BBI-Cl-M@PMMA). Specifically, the ester functionalized bibenzimidazole with modified chlorine on molecular skeleton (BBI-Cl-M) demonstrates a remarkable phosphorescent lifetime (τp) of up to 256.4 ms. In addition, the behaviors and mechanism of RTP via polyatomic synergistic effect have been further understood by theoretical calculation and single crystal analysis. Subsequently, utilizing BBI-Cl-M as the energy donor and Rhodamine B (RB) as the energy acceptor, persistent and multicolor organic afterglow covering from green to red has been realized successfully by simply regulating the doping composition and concentration of PRET systems. These RTP materials have also been applied in underwater afterglow emission and multilevel anti-counterfeiting technology successfully.
Carbon dots (CDs)-based composites have shown impressive performance in fields of information encryption and sensing, however, a great challenge is to simultaneously implement multi-mode luminescence and room-temperature phosphorescence (RTP) detection in single system due to the formidable synthesis. Herein, a multifunctional composite of Eu&CDs@pRHO has been designed by co-assembly strategy and prepared via a facile calcination and impregnation treatment. Eu&CDs@pRHO exhibits intense fluorescence (FL) and RTP coming from two individual luminous centers, Eu3+ in the free pores and CDs in the interrupted structure of RHO zeolite. Unique four-mode color outputs including pink (Eu3+, ex. 254 nm), light violet (CDs, ex. 365 nm), blue (CDs, 254 nm off), and green (CDs, 365 nm off) could be realized, on the basis of it, a preliminary application of advanced information encoding has been demonstrated. Given the free pores of matrix and stable RTP in water of confined CDs, a visual RTP detection of Fe3+ ions is achieved with the detection limit as low as 9.8 µmol/L. This work has opened up a new perspective for the strategic amalgamation of luminous guests with porous zeolite to construct the advanced functional materials.
2, 6-Diisopropylaniline reacts with an open-cage fullerene derivative with a 11-membered orifice and forms an open-cage derivative containing one imino group on the rim of the expanded orifice. Further treatment with Lewis acids leads to open-cage fullerenes with an 18-membered orifice. Instead of the direct addition process observed before for less bulky anilines, an electron transfer process takes place in the initial step in the present reaction with bulky 2, 6-diisopropylaniline. As a result, the chemo-selectivity is completely different affording the mono imino open-cage derivative selectively.
Regioselevtive functionalization of perylene diimides (PDIs) at bay area often requires multistep synthesis and strenuous recrystallization. Direct bromination of perylene diimides only afford the 1, 6 and 1, 7-regioisomers. More importantly, the 1, 6-dibromo regioisomers could only be separated by preparative HPLC. Herein, we report a promising strategy for constructing Janus backbone of BN-doped perylene diimide derivatives. This Janus-type configuration results in the unique regioselective functionalization of BN-JPDIs, which yields exclusively the 1, 6-regioisomers. Further investigation shows that the Janus-type configuration leads to a net dipole moment of 1.94 D and intramolecular charge transfer, which causes substantial changes on the optoelectronic properties. Moreover, the single crystal organic field-effect transistors based on BN-JPDIs exhibit electron mobilities up to 0.57 cm2 V−1 s−1, showcasing their potential as versatile building block towards high-performance n-type organic semiconductors.
Benziodazole-triflate, as a novel heterocyclic hypervalent iodine(Ⅲ) reagent, was prepared from the reaction of hypervalent chloroiodine(Ⅲ) with silver triflate under mild conditions. The structure of this new reagent was elucidated by NMR spectroscopy and X-ray crystallography, and its reactions with diverse α-electron withdrawing group substituted carbonyl compounds were investigated. The results implied that benziodazole-triflate could be selectively used as both a 2-iodobenzamido-transfer reagent for the synthesis of oxazole compounds, and a triflate-transfer reagent for the triflation of β-keto-sulfones. Ionic mechanistic pathways, supported by density functional theory (DFT) calculations, were proposed to account for the divergent selectivities of the transformations.
Advanced oxidation processes (AOPs) governed by peroxide activation to produce highly oxidative active species have been extensively explored for environmental remediation. Nevertheless, the low diffusion rates, inadequate interactions of the reactants, and limited active site exposure hinder treatment efficiency. Porous carbocatalysts with high specific surface area, tunable pore size, and programmable active sites demonstrate outstanding performance in activating diverse types of peroxides to generate active species for treatment of aqueous organic pollutants. The pore-rich structures enhance reaction kinetics for peroxide activation by facilitating diffusion of the reactants and their interactions. Additionally, the structural flexibility of porous structures favors the accommodation of highly dispersed metal species and allows for precise tuning of the microenvironment around the active sites, which further enhances the catalytic activity. This review critically summarizes the recent research progress in the applications of engineered porous carbocatalysts for peroxide activation and outlines the prevailing pore construction methods in carbocatalysts. Moreover, engineering strategies to regulate the mass transfer efficiency and fine-tune the microenvironment around the active sites are systematically addressed to enhance their catalytic peroxide activation performances. Challenges and future research opportunities pertaining to the design, optimization, mechanistic investigation, and practical application of porous carbocatalysts in peroxide activation are also proposed.
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
