Latest ArticlesAntibiotic resistance poses a critical threat to human healthcare, largely driven by bacterial biofilms. These biofilms resist the immune system and antibiotics, rendering enclosed microbial cells 10–1000 times more antibiotic-resistant than planktonic cells, leading to severe infections. Therefore, there is an urgent need to develop innovative tools for investigating biofilm regulators and devising novel antibacterial strategies. In this study, we developed Cy-NEO-PA, a near-infrared (NIR) fluorescent probe responsive to penicillin G acylase (PGA), with bacteria-targeting ability. This probe was designed to visualize the influence of environmental factors on biofilm formation in Acinetobacter baumannii (A. baumannii). Our findings demonstrated that glucose suppressed PGA production, leading to enhanced biofilm formation, whereas phenylacetic acid (PAA) stimulated PGA production and inhibited biofilm formation in A. baumannii. These observations highlight the remarkable capability of Cy-NEO-PA to accurately measure PGA dynamics, shedding light on the critical role of PGA in biofilm development. Additionally, Cy-NEO-PA exhibited excellent biocompatibility, potent reactive oxygen species (ROS) generation, efficient photothermal conversion, and bacteria-targeting abilities, making it a promising agent for combating bacterial infections and promoting wound healing through photothermal (PTT)/photodynamic (PDT) therapy. These discoveries emphasize the significant role of PGA in antibacterial therapy and offer valuable insights for the design of effective strategies targeting PGA to combat biofilm-associated infections.
Reported here is the synthesis of a new macrocycle bearing anionic carboxylate groups with water-soluble aggregation-induced emission (AIE). The water-soluble macrocycle without typical AIE luminogens is constructed based on the building block of benzothiadiazole. It exhibits a remarkable AIE effect. This water-soluble macrocycle can selectively bind different types of biogenic amines in aqueous media with the tightest binding towards spermine. The fluorescence enhancement induced by supramolecular encapsulation is used to detect spermine.
3d transition metal chalcogenides have attracted much attention due to their unique magnetic properties. Although various Cr, V, and Fe-based chalcogenides have been fabricated recently, the limited Curie temperature (TC) still hinders their practical application. Based on the structural and magnetic advantages of MFe2O4 and Fe3Se4, we developed a one-pot solution synthesis method for the fabrication of NiFe2Se4 nanostructures with structural continuity, to facilitate the investigation of their magnetic properties. Notably, the morphology of NiFe2Se4 can be controlled from nano-rods to nano-platelets by controlling the growth direction. The coercivity (HC) of NiFe2Se4 with nano-cactus structure exhibits a maximum of 12.77 kOe at 5 K. The coercivity of ferrimagnetic NiFe2Se4 nano-platelets can be further adjusted to 1.52 kOe at room temperature. These results show that the magnetic properties of NiFe2Se4 can be significantly modified by controlling their morphologies. We also extend the method to the synthesis of CoFe2Se4 nano-cactus with an ultrahigh coercivity of 17.85 kOe at 5 K. Obviously, the synthesis strategy and their excellent magnetic properties of MFe2Se4 have sparked interest in ternary transition metal selenides as potential hard magnetic materials.
Roxarsone (ROX) is a commonly used antibacterial and growth-promoting additive to animal feed. The development of an effective method for detecting ROX and its conversion products is of importance because of their potential harm to human health and ecosystem. Herein, we report the designed synthesis of a novel one-dimensional covalent organic framework (1D COF), named EP-COF, and its application as a fluorescent probe for ROX sensing. EP-COF is constructed based on imine linkages, exhibiting high crystallinity, strong fluorescence emission, and good dispersibility in water. It displays a remarkable capability to efficiently detect ROX, with an impressive detection limit of 4.5 nmol/L. Moreover, EP-COF also offers advantages of excellent selectivity, and high structural stability. This work not only presents a promising approach for the detection of harmful substances like ROX, but also serves as a valuable reference for exploring application of 1D COFs in chemical sensing.
In order to solve the problem of poor conductivity of traditional LiFePO4 cathode binders, we developed sodium alginate-Congo red copolymers (SA-CR) as water-soluble electrically conductive and mechanically robust composite binder. Unlike most other electrically conductive polymer binders, the procedure is straightforward and low-cost to prepare SA-CR binder. Various SA -CR copolymers were prepared with different degree of compounding of CR to investigate the effect of CR on the electrochemical and physical properties of the prepared electrodes. The copolymer whose composition was filled with a mixture of SA and CR at a 3:1 mass ratio showed the best cell performance, due to the well-balanced electrical conductivity and mechanical properties. It exhibited a specific capacity of 118.8 mAh/g at the 100th cycle with 92.1% capacity retention, significantly better than the 108.5 mAh/g of conventional acetylene black electrodes. CR as a conduction-promoting agent in water-soluble composite binder favors the formation of continuous and homogenous conducting bridges throughout the electrode and increases the compaction density of electrode by reducing the conducting agent content of acetylene black and thus the improvement of electrode performance is realized.
A new 1,4-amidocyanation of 1,3-enynes with N-amidopyridin-1-ium salts and TMSCN using a copper and photoredox synergetic catalysis for producing α-amido allenyl nitriles is developed. Employing N-amidopyridin-1-ium salts as the amidyl radical precursors, the reaction enables the formation of two new bonds, one C(sp3)-N bond and one C(sp2)-C(sp) bond, in a single reaction step. This reaction represents a mild, general route to the construction of the α-amido allenyl nitrile architectures, which characterizes a broad scope, a good functional group compatibility and an excellent selectivity.
1-(4-(1,1-Dimethylethyl)phenyl)-3-(4-methoxyphenyl)-1,3-propanedione (known as Avobenzone/AVB), widely used throughout the world as a highly effective UVA absorber, can prevent the progression of photoaging in skin, and is also known for the disadvantage of having a reduced capability to absorb UVA when exposed to sunlight for long periods. To address this challenge, ZnTi-CO3-LDH with a two-dimensional layered structure was used to improve stability and synergistically enhance UV absorption of AVB. A novel AVB loaded ZnTi-CO3-LDH (AVB@ZnTi-LDH) material was synthesized by reconstruction method and the loading content (LC) was about 46.8% investigated by high-performance liquid chromatography (HPLC). A possible mechanism for the binding of AVB with the ZnTi-LDH surface was proposed. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations were used to confirm further the coordination between Zn on the layer and the oxygen atom of the carbonyl group of AVB. UV absorption and critical wavelength of AVB@ZnTi-LDH were superior to those of AVB and ZnTi-LDH precursors. Compared with pure AVB, the photodegradation rate was reduced from 15.06% to 4.06%. Especially in titanium dioxide, the decomposition rate was reduced from 29.75% to 7.92%. Furthermore, pure AVB often reacts with multivalent metal ions to induce an unpleasant color (light yellow to reddish brown), which is greatly mitigated with AVB@ZnTi-LDH. In this study, avobenzone was combined with hydrotalcite to prepare an organic-inorganic composite with excellent UV resistance and better stability, the composite has great promise for application in sunscreen cosmetics.
SnO2 is a potential anode material with high theoretical capacity for lithium-ion batteries (LIBs), however, its applications have been limited by the severe volume expansion during charging-discharging process. In this work, an inverse opal TiO2/SnO2 composite with an interconnect network nanostructure was designed to confine SnO2 nanoparticles in the porous TiO2. Due to this nanoconfinement structure, the volume expansion in the process was effectively alleviated, therefore the safety performance and cycling stability of the battery were effectively improved. At the same time, with a large number of microporous structures in the framework, the appearance of pseudocapacitance improves the rate performance and reversible capacity. In terms of electrochemical kinetics, its framework provides the connected path for charge migration, effectively reducing the charge transfer impedance, meanwhile, quantities of micropores in its skeleton could provide a smoother channel for lithium ions, thus greatly improving the diffusion rate of LIBs. The design of this nanostructure provides a new idea for the research of SnO2-based anode with effectively enhanced electrochemical performance, which is promising anode for practical application.
A novel Ce-containing poly(tungstobismuthate) Cs18Na8H20[Ce3(H2O)10W8Bi4O28(B-α-BiW9 O33)4]2·64H2O (1) has been synthesized by a facile one-pot self-assembly reaction strategy. Its structural characterization is realized by virtue of single-crystal X-ray diffraction, infrared spectroscopy, powder X-ray diffraction and thermogravimetric analysis. The polyoxoanion of 1 is an octameric architecture consisting of two tetrameric entities [Ce3(H2O)10W8Bi4O28(B-α-BiW9O33)4]23− linked by two CeOW bonds, and adjacent polyoxoanions are further combined together by means of Ce3+ linkers, resulting in an infinite 1D chain architecture. Compound 1 is the currently largest tungstobismuthate, and also represents the first example of lanthanide-encapsulated tungstobismuthate exhibiting an extended structure. Furthermore, compound 1 as a heterogeneous catalyst, exhibits high activity for the oxidative decontamination of a sulfur mustard simulant, 2-chloroethyl ethyl sulfide (CEES) into 2-chloroethyl ethyl sulfoxide (CEESO).
Clinical phototheranostic agents suffer from low absorption in near-infrared (NIR) region, decreasing singlet oxygen quantum yield (1O2 QY) caused by aggregation in water, and low photothermal conversion efficiency (PCE), all of which are factors weakening their phototheranostic efficacy. Herein, we designed and synthesized a donor-acceptor-donor (D-A-D) structured boron-dipyrromethene derivative (B-2TPA) which exhibited NIR absorption and fluorescence. After being encapsulated in amphiphilic distearoyl phosphoethanolamine polyethyleneglycol 2000 (DSPE-PEG-2000), the water-soluble B-2TPA nanoparticles (NPs) had increasing 1O2 QY (6.7%) due to the intermolecular aggregation-induced decrease in the energy gap between singlet and triplet excited states. Moreover, the quenched fluorescence and stable twisted intramolecular charge transfer in aggregates further increased the PCE of B-2TPA NPs to 60.1%. In vitro and in vivo studies confirmed that B-2TPA NPs could be used in NIR fluorescence and photoacoustic imaging-guided synergistic photodynamic and photothermal therapy in tumor treatment.
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
