New Journal of Chemistry最新文献

DNA methyltransferase (DNA MTase) catalyzes DNA methylation, which plays a crucial role in various biological processes such as chromatin assembly, aging, and tumorigenesis. For this reason, developing handy DNA MTase assays and screening its inhibitors have potential value in clinical applications. Here, we have established a label-free strategy for Dam MTase, using the T7 RNA transcription system for signal amplification and its transcription product malachite green aptamer (MGA) for signal transduction. This strategy reached a detection limit of 9.95 × 10⁻⁵ U mL⁻¹ and successfully achieved detection in a complex biological matrix. Simultaneously, this method has realized the screening of methyltransferase inhibitors, laying a solid foundation for its clinical application.

A novel ternary polymer of sodium titanate/graphite oxide/polyurethane (sodium titanate/GO/PUP) was synthesized in this work as an adsorbent for eliminating radioactive strontium from wastewater. Multiple techniques, such as XRD, FT-IR, SEM, TEM, BET and XPS, were used to characterize its morphology and physicochemical properties. Kinetic experimental data on Sr²⁺ fitted better with the pseudo-second-order model, with an adsorption rate of 99.4%, and the adsorption isotherm followed the Langmuir isotherm model, with a maximum adsorption capacity of 104.71 mg g⁻¹. The adsorbed Sr²⁺ ions were trapped permanently in the composite. The possible mechanism for Sr²⁺ removal was found to be ion exchange, with an unexpected mole ratio of nearly 1 : 1 between absorbed Sr²⁺ and exchanged Na⁺. Both pH and temperature were found to influence the adsorption process. Further, the results of phytotoxicity assessment indicated that sodium titanate/GO/PUP had no obvious biotoxicity, and the toxicity of Sr²⁺ wastewater was significantly reduced after treatment. Therefore, sodium titanate/GO/PUP is a safe and effective adsorbent for radioactive wastewater treatment and environmental remediation.

Periodontitis is a chronic disease that can lead to irreversible tooth loss and decreased quality of life, highlighting the importance of timely monitoring. Meanwhile, hydrogen sulfide (H₂S) in saliva, produced by periodontal pathogens, is a significant biomarker for monitoring periodontitis. However, the simple and portable operation required to achieve high sensitivity remains a technical challenge for directly sensing exhaled breath. In this study, by integrating the fluorescent indicator (sodium 1-pyrenebutyrate, PB) into a covalent organic framework (COF, EB-TFP), an indicator displacement assay (IDA)-based fluorescence enhanced gas sensor (EB-TFP@PB) was constructed. With the selective binding of H₂S to EB-TFP, the sensor substantiated excellent sensitivity, with a limit of detection (LOD) of 1.44 ppb for H₂S gas. In addition, EB-TFP@PB showed selective antibacterial activity against Staphylococcus aureus (S. aureus) under non-illuminated conditions. The antibacterial mechanism of EB-TFP@PB was further investigated using electron microscopy-related techniques. This work not only offers a reliable and sensitive design for noninvasive medical diagnosis of H₂S detection based on the IDA strategy but also provides a new idea for developing highly selective antibacterial COF composite materials.

In the current work, two new bifunctional Brønsted–Lewis acidic chloronickellate ionic liquid systems, 1a and 1b ([RSIM]_x[NiCl_y], where R = C₂H₅ and CH₃, x = 2, y = 2, 3, 4 or 5), were developed by incorporating two –SO₃H groups into the imidazolium cation. These chloronickellate ionic liquids (ILs) were then utilized as precursors/templates in the synthesis of nickel sulphide nanosheets (2a and 2b) using a simple grinding method. The synthesized nanosheets were characterized using PXRD, FT-IR, RAMAN, TEM, SEM-EDX, XPS, BET and UV-visible analysis. The photocatalytic activities of these nanosheets were then explored in the degradation of organic dyes (methylene blue, methyl orange, crystal violet and malachite green) and their mixtures in the presence of sunlight. The nanosheet 2a exhibited excellent degradation efficiency of 98.38% for methylene blue at pH = 7. The recyclability study established the stability and feasibility of multiple utilizations of the photocatalyst, supporting its potential implementation in water remediation.

A new decontamination textile involving a cyclodextrin derivative bearing an iodosobenzoate group was developed. It proved its efficiency against soman to decontaminate solid surfaces and to allow up to 3- to 4-fold improvement in accelerating the hydrolysis of the toxic compound under mild conditions. This opens the way to new technologies for decontamination of tools and designing of self-decontaminating protective equipment against chemical weapons.

Herein, we present an efficient and sustainable approach to the Heck–Mizoroki (HM) and Suzuki–Miyaura (SM) cross-coupling reactions catalyzed by Pd nanoparticles dispersed in water. The protocol eliminates the need for organic co-solvents, phosphine ligands, or inert atmosphere, making it environmentally benign. The inclusion of novel branched imidazolium sulfonate-based zwitterionic additives (ImS3b-n) significantly enhances the solubility and mixing of hydrophobic reactants, optimizing reaction conditions. The catalytic system demonstrated excellent reusability, with both Pd nanoparticles and the additives recovered and reused for four cycles in the HM reaction between ethyl acrylate and iodobenzene, achieving a remarkable total turnover number (TON) of 8821 for ethyl cinnamate. Furthermore, the Pd nanoparticles effectively catalyzed the SM reactions of aromatic boronic acids. Both reactions were successfully scaled up to the gram level, maintaining exceptional reproducibility compared to small-scale reactions. The methodologies developed here not only utilize low Pd loading (0.03 mol%) but also obviate the need for chromatography purification, offering a streamlined, greener alternative for cross-coupling reactions. This work underscores a commitment to advancing Green Chemistry principles while achieving high efficiency and practicality in catalysis.

Expression of Concern for ‘Facile synthesis and investigation of 1,8-dioxooctahydroxanthene derivatives as corrosion inhibitors for mild steel in hydrochloric acid solution’ by Behrooz Maleki et al., New J. Chem., 2016, 40, 1278–1286, https://doi.org/10.1039/C5NJ02707A.

The recycling of spent LiFePO₄ batteries has garnered significant attention due to its environmental benefits and economic potential. During the practical recycling process, direct crushing and sorting of cathode materials typically produce a black powder containing various metal impurities. The high impurity content in these powders hinders the direct reuse of spent LiFePO₄ cathode materials. This paper presents a novel, simple, and efficient method for impurity removal. The process begins with sieving the black powder obtained from crushed LiFePO₄ cathode materials to effectively separate the cathode active materials from aluminum and copper foils. Alkaline and acid leaching processes are subsequently employed to remove multiple metal impurities, including aluminum, chromium, nickel, and manganese, from the active materials. The resulting leachate is used to prepare battery-grade FePO₄, which is then combined with L_i2CO₃ through a carbothermic reduction process to synthesize LiFePO₄/C. The re-synthesized LiFePO₄/C cathode demonstrates an initial discharge capacity of 155.1 mA h g⁻¹ and retains 96.4% of its electrochemical performance after 100 cycles at a 0.2C rate, meeting the performance requirements for mid-range LiFePO4 batteries. The entire process is eco-friendly and holds significant potential for large-scale recycling of used lithium-ion batteries.

The photocatalytic nitrogen reduction reaction provides an alternative process for nitrogen cycling and ammonia (NH₃) production under mild conditions. Herein, we have synthesized Ag-loaded In₂O₃ (Ag@In₂O₃-X) by solvothermal and photoreduction methods. The introduction of Ag significantly alters the band structure of In₂O₃, resulting in a slight reduction in the band gap and a more negative conduction band position, thereby facilitating the generation of reductive electrons in In₂O₃. Moreover, the synergistic interaction between loaded Ag nanoparticles and In₂O₃ forms a Schottky barrier, which widens the light absorption range and promotes charge separation. Under simulated sunlight, the photocatalytic nitrogen fixation performance of Ag@In₂O₃-5 reaches 35.56 μmol h⁻¹ g_cat⁻¹, which is higher than other composites and 3.58 times that of pure In₂O₃. At the same time, the catalyst has good structural stability and cycle life. Density functional theory (DFT) calculations demonstrate that Ag exhibits a stronger interaction with N₂ and lowers the potential barrier of the N₂ hydrogenation reaction. The synergistic effect between precious metals and semiconductors offers novel insights and presents challenges for the photocatalytic N₂ fixation process. This work provides new insights and challenges for designing and synthesizing nanomaterials for photocatalytic nitrogen fixation.

Blended nylon-cotton (NYCO) fabric is frequently used due to its unique combination of comfort and strength, but it suffers from high flammability. Flame-retardant NYCO is created by applying a simple two-step process of an eco-friendly, water-based polyelectrolyte complex consisting of egg white proteins (EWP), pectin (P), and guanidine phosphate (GP). The addition of GP to the EWP/P system facilitates charge screening of the P macromolecule, allowing a sufficient coating to form and impart flame-retardant properties to the fabric. The NYCO fabric coated with a positively charged 4% EWP solution at pH 3 and a negatively charged 1% P + 20% GP solution at pH 3 exhibits self-extinguishing behavior during vertical flame testing and retains mechanical properties similar to those of the uncoated fabric. This coating modifies the thermal degradation behavior of NYCO by promoting the formation of an intumescent charred layer that protects the fabric from further decomposition. As a result, the coated fabric shows 10.8% residue at 700 °C in air and 29.2% in nitrogen, which is significantly higher than the uncoated fabric, which retains only 2.5% residue in air and 10.4% in nitrogen. Additionally, the coated fabric releases 32.6% less heat and exhibits a 37.9% reduction in fire growth capacity. This simple and completely bio-based coating provides an effective and benign way to protect this important class of textiles from fire.