Latest ArticlesElectrocatalytic synthesis of urea through CN bond formation, converting carbon dioxide (CO2) and nitrate (NO3–), presents a promising, less energy-intensive alternative to industrial urea production process. In this communication, we report the application of Mo2C nanosheets-decorated carbon sheets (Mo2C/C) as a highly efficient electrocatalyst for facilitating CN coupling in ambient urea electrosynthesis. In CO2-saturated 0.2 mol/L Na2SO4 solution containing 0.05 mol/L NO3–, the Mo2C/C catalyst achieves an impressive urea yield of 579.13 µg h–1 mg–1 with high Faradaic efficiency of 44.80% at –0.5 V versus the reversible hydrogen electrode. Further theoretical calculations reveal that the multiple Mo active sites enhance the formation of *CO and *NH2 intermediates and facilitate their CN coupling. This research propels the use of Mo2C-based electrodes in electrocatalysis and accentuates the capabilities of binary metal-based catalysts in CN coupling reactions.
In this study, three-dimensional microspherical CQDs/Bi2MoO6 heterostructures were synthesized using a simple alcohol-thermal method. It was found that the CQDs/Bi2MoO6 had a large specific surface area of 56.0 m2/g, and the introduction of CQDs extended the light absorption spectrum from 480 nm to 496 nm. When utilizing the synthesized CQDs/Bi2MoO6 composite for photocatalytic degradation of antibiotic norfloxacin in a water environment, complete decay of norfloxacin and effective removal of total organic carbon (TOC) were achieved within 30 min. Through the optimization of material synthesis and experimental conditions, the optimal CQDs loading amount was determined as 200 µL, the optimal CQDs/Bi2MoO6 dosage was 0.8 g/L. Moreover, the CQDs/Bi2MoO6 worked well under a wide pH range of 4.4–10.8. The coexistence of HCO3− enhanced the norfloxacin decay, while the presence of Cl−, NO3−, and SO42− slightly retarded it. The synthesized CQDs/Bi2MoO6 had the great potential in removing and mineralizing norfloxacin in real aquatic environments.
Essential amino acids (EAAs) deprivation is a potential antitumor approach because EAAs are critical for tumor growth. To efficiently inhibit tumor growth, continuous deprivation of EAAs is required, however, continuous deprivation without precise control will introduce toxicity to normal cells. Herein, a programmable double-unlock nanocomplex (ROCK) was prepared, which could self-supply phenylalanine ammonia-lyase (PAL) to tumor cells for phenylalanine (Phe) deprivation. ROCK was double-locked in physiological conditions when administered systemically. While ROCK actively targeted to tumor cells by integrin αvβ3/5 and CD44, ROCK was firstly unlocked by cleavage of protease on tumor cell membrane, exposing CendR and R8 to enhance endocytosis. Then, hyaluronic acid was digested by hyaluronidase overexpressed in endo/lysosome of tumor cells, in which ROCK was secondly unlocked, resulting in promoting endo/lysosome escape and PAL plasmid (pPAL) release. Released pPAL could sustainably express PAL in host tumor cells until the self-supplied PAL precisely and successfully deprived Phe, thereby blocking the protein synthesis and killing tumor cells specifically. Overall, our precise Phe deprivation strategy effectively inhibited tumor growth with no observable toxicity to normal cells, providing new insights to efficiently remove intratumoral nutrition for cancer therapy.
Metabolism encompasses a series of intricate biochemical processes that are vital for the sustenance of life in organisms. Metabolomics, an essential scientific discipline, is a field of study within the broader domain of systems biology that focuses on the comprehensive analysis of small molecules, known as metabolites including lipids, coenzymes, etc., which are synthesized during metabolism. With the continuous development of metabolomics, the multiple biological functions of metabolites are constantly being discovered, encompassing signal transduction and enzyme stimulation, while concurrently exhibiting associations with afflictions like cancer and diabetes. The comprehension of metabolite functionalities and their intricate interplay with disease conditions assumes paramount importance in both disease-focused research endeavors and the development of diagnostic tools. This scholarly exposition undertakes an extensive review of recent advancements in the investigation of functional roles assumed by metabolites, with specific emphasis on metabolites in lipid synthesis, glucose metabolism and exogenous metabolites.
Transition-metal-catalyzed remote sp2C—H functionalization of aryl sulfonic acids was hardly ever realized owing to competitive ortho-C—H functionalization of aryl sulfonates and electron-deficient nature of phenyl ring. Herein, with the assistance of a practical biaryl indolyl directing template, palladium-catalyzed remote sp2C—H alkylation of aryl sulfonic acids have been achieved in moderate to good yields with exclusive meta selectivity. Moreover, remote meta-selective C—H alkynylation of aryl sulfonic acids was also accomplished with a rhodium catalyst. These meta-C—H functionalized products proved to be the superior synthetic precursors, which are difficult to access using the conventional strategy.
The monkeypox virus (MPXV) outbreak, declared a Public Health Emergency of International Concern (PHEIC) by the World Health Organization (WHO) in 2022, continues to pose a significant threat due to the absence of vaccines or drugs for MPXV infection. In this study, we developed an mRNA vaccine that expressing the A29L antigen, a specific protein of the intracellular mature virus. Our vaccine utilizes a thermostable ionizable lipid nanoparticle (iLNP) platform and has been administered to mice. Our findings demonstrate that the MPXV A29L mRNA vaccine candidate induces robust cross-neutralizing immune responses against both vaccinia virus (VACV) and MPXV live virus. Furthermore, immunization with the vaccine candidate provided protection against the VACV challenge in mice. These findings underscore the potential of mRNA-LNP vaccines as safe and effective candidates against monkeypox epidemics. Given the current absence of specific interventions for MPXV infection, our study represents a significant step forward in developing a viable solution to combat this ongoing public health threat.
In this contribution, we describe the preparation and recognition characteristics of a novel tetrapodal benzene cage (1). The cage can express a wide recognition range without losing selectivity for the object of appropriate size and functional groups. The key to obtaining the desired structural isomer of 1 is the synthesis and isolation of the o-bis(bromomethyl)benzene precursor (5). Three distinct guests, F− (extremely small size), D-lactate (appropriate size) and L-Asp (branched shape), were selected as examples to demonstrate the recognition characteristics of 1. By NMR titration studies, they all expressed good binding affinity (K > 105 L/mol) in competitive medium (10% DMSO/THF), indicating that 1 has a wide recognition scope. The highest binding constant was observed for D-lactate, revealing that 1 has good selectivity for D-lactate versus F− and L-Asp. Moreover, the NMR titration study of F− in DMSO indicates 1 can achieve different binding modes (1:1 and 2:1 guest-host) for small-sized guests, which allows for the further development of binary binding properties and thereafter applications in the field of catalysis.
Sulphur (S)-template method based on conventional slurry-casting method has been developed to produce porous silicon (Si) electrodes. The facile fabrication technology is suitable for current production line and expected to be widely applied to various electrode materials under large volume change during operation. Specifically, S particles as template agent are mixed with active material Si, carbon conductor and binder forming uniform slurry. After casting and drying, the electrodes are immersed in carbon disulfide solution to remove S particles rapidly, generating pores in-situ at the original position of S particles. Electrochemical analysis shows that the pores inside electrodes are able to shorten lithium ion diffusion paths, reduce normal expansion rate and decrease formation of cracks in the Si electrode (2 mgSi/cm2), demonstrating a reversible capacity of 951 mAh/g at 0.5 A/g after 100 cycles (with a capacity retention of 99.5%) and a capacity of ~826 mAh/g at 2 A/g.
Photocatalytic synthesis of hydrogen peroxide has gradually become a promising method for in-situ production of hydrogen peroxide, which relies on sustainable solar energy. However, the commonly used photocatalyst, i.e., carbon nitride (CN), still suffers from the drawbacks of narrow light absorption range and fast charge recombination. Here, we report a facile method to introduce nitrogen defects into carbon nitride together with sodium ion. By adjusting the ratio of sodium dicyandiamide, the band gap of carbon nitride can be controlled, while the carrier separation and transfer ability of carbon nitride is improved. The modified CN with sodium doping and nitrogen defect (SD-CN) demonstrates outstanding H2O2 production performance (H2O2 yield rate of 297.2 µmol L−1 h−1) under visible light irradiation, which is approximately 9.8 times higher than that of pristine CN. This work deepens the understanding of the coordinated effect of structural defect and element doping of carbon nitride on the photocatalytic H2O2 production performance, and provides new insight into the design of photocatalytic system for efficient production of H2O2.