Journal of The Chinese Chemical Society最新文献

Vascular endothelial growth factor (VEGF165) is a homodimeric protein that plays a key role in tumor formation and progression. Therefore, early determination of blood levels of VEGF165 is vital in the diagnosis and successful treatment of different types of cancers. In the present study, a novel sandwich-type biosensor was designed for sensitive and selective determination of VEGF165 in human blood serum samples. Carbon dots (CDs) were used as inexpensive and conductive nanomaterials for immobilization of the antibody (Ab) on the electrode surface. The prepared carbon dots were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), FT-IR, UV–Visible spectrophotometry, and spectrofluorimetry. Highly fluorescent particles were formed due to the quantum restrictions brought about by their ultrasmall size (average size ~10 nm). The high surface-to-volume ratio of carbon dots, as well as the presence of many oxygen-containing functional groups, was appropriate for attachment of large amounts of Ab moieties. In the presence of VEGF165, a highly selective VEGF165-Ab complex was formed on the electrode surface, which was then bound to the added selective aptamer to form Aptamer-VEGF₁₆₅-Ab. As the electrochemical probe, methylene blue (MB) was used, which has a high binding tendency to guanine bases of the aptamer (MB-Aptamer-VEGF165-Ab) on the electrode surface, which resulted in well-known MB⁺/MB redox peaks. A linear relationship was obtained between peak currents and log [VEGF165] in the wide concentration range of 0.01 pM to 10 nM (0.34–34 × 10⁶ pg/mL) by differential pulse voltammetry (pH 7.4, 0.1 M PBS). The limit of detection (LOD) was calculated as 3.3 fM (0.112 pg/mL) based on S/N = 3. The proposed biosensor was successfully applied to the determination of VEGF165 in blood serum samples of patients with lymphoma cancer.

This study reports the direct hydrothermal growth of α-MnO₂ on carbon fiber textile without the use of polymeric binders, yielding a unique “spider-egg-like” morphology. Unlike conventional MnO₂-based cathodes, where active materials require binders and conductive additives, this approach ensures strong adhesion to the substrate while maintaining high conductivity and mechanical stability. SEM revealed spherical MnO₂ structures entangled within a nanowire network, creating a porous, interconnected architecture that enhances ion diffusion and charge transfer. XRD confirmed the formation of crystalline α-MnO₂, while EDS and XPS validated its elemental composition and mixed-valence states, highlighting its redox activity. Electrochemical characterization demonstrated its potential as a cathode for ARZIBs, delivering an initial capacity of 367 mAh/g. The composite maintained stable discharge capacities of 218, 120, 102, and 79 mAh/g at 0.1C, 0.3C, 0.5C, and 1C, respectively, with 88.94% capacity retention over 350 cycles. Its long-term stability and nearly 100% Coulombic efficiency confirm the robustness of the direct-growth architecture in facilitating reversible Zn²⁺ intercalation. The binder-free synthesis method presents a scalable and eco-friendly alternative to conventional electrode fabrication, reducing processing steps while improving electrochemical performance. This study introduces a novel approach to designing MnO₂ cathodes, offering a high-performance, mechanically stable, and conductive material for next-generation ARZIBs.

In this study, Bi₂WO₆/BiOBr S-scheme heterojunction composites were synthesized via a one-step solvothermal method. The experimental results demonstrate that the Bi₂WO₆/BiOBr composites exhibit a significant redshift in the light absorption edge and a reduction in bandgap compared with that of individual Bi₂WO₆ and BiOBr. Meanwhile, the separation and transfer of photogenerated carriers were accelerated in Bi₂WO₆/BiOBr composites. In the photocatalytic degradation of tetracycline, the best composite displayed the highest photocatalytic activity, achieving a degradation efficiency of 91.3% after 60 min of light irradiation. Moreover, it maintained good stability even after four cycles. The enhancement in photocatalytic activity is primarily attributed to the formation of the S-scheme heterojunction and the strengthened interfacial interactions.

The increasing demand for cost-effective and efficient drug delivery systems has catalyzed interest in biocompatible materials like cellulose-based hydrogels. This study presents the development and optimization of cellulose-based hydrogel films for the controlled release of levofloxacin, addressing challenges in drug stability and targeted delivery. The films, synthesized using hydroxypropyl methylcellulose (HPMC), carboxymethyl cellulose (CMC), and polyethylene glycol, were confirmed via FTIR analysis to involve physical cross-linking and hydrogen bonding. SEM analysis revealed that the composition significantly impacts surface morphology and pore structure, with higher CMC content producing larger micropores due to electrostatic interactions. Employing a central composite design under response surface methodology, the mechanical properties, including tensile strength, Young's modulus, elongation, and swelling, were optimized for performance and efficiency. A refined RP-HPLC method, validated for high accuracy, precision, and sensitivity, demonstrated recovery rates between 97.69% and 99%, providing a reliable and time-efficient tool for levofloxacin quantification. Drug release studies indicated that polymer composition plays a critical role in release kinetics, with higher HPMC content promoting faster release and higher CMC content enabling sustained release, aligning with the Peppas model for a diffusion-relaxation-erosion mechanism. This study highlights the innovation of integrating cellulose-based hydrogels with validated, cost-effective analytical methods to deliver a scalable, time-efficient drug delivery solution. The findings offer valuable insights into the development of advanced drug delivery systems, demonstrating the potential of these hydrogels for broader therapeutic applications.

The development of electrocatalysts based on non-noble metals is vital for advancing the Hydrogen Evolution Reaction (HER) in water electrolysis, a key process for clean energy production. In this study, one-dimensional (1D) nanowires were synthesized on Molybdenum/Nickel Foam (MNF) using a solvothermal approach, with a focus on the impact of varying heating durations. Electrocatalytic performance was assessed through Tafel analysis across high and low potential regions using polarization plots. The sample heated for 12 h at 160°C demonstrated an overpotential of 158.8 mV at a current density of 10 mA/cm², with Tafel slopes ranging from 489 to 254 mV/dec across different potential regions. Furthermore, structural and compositional analyses were conducted using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) techniques. In addition, charge transfer kinetics were studied using electrochemical impedance spectroscopy (EIS) and stability tests were also conducted to test the catalyst performance under longer time periods.

Magnetoelectric core-shell nanoparticles (ME CSNPs) have gained significant attention for their potential applications in multifunctional devices. We investigate the electrical stability of ZnFe₂O₄-BaTiO₃ ME CSNPs (ZFO-BTO ME CSNPs) under various external bias voltages. The phase composition of the core-shell nanoparticles was determined through Rietveld refinement of X-ray diffraction data, indicating a tetragonal BaTiO₃ shell and cubic ZnFe₂O₄ core, present in a weight ratio of 63.63:35.20. Transmission electron microscopy (TEM) analysis shows that the core is composed of ZnFe₂O₄ with a diameter of 30–50 nm, surrounded by a BaTiO₃ shell with a diameter ranging from 100 to 400 nm. Piezoresponse force microscopy (PFM) results demonstrate that ZFO-BTO CSNPs exhibit a stable core-shell configuration up to 1 V, beyond which structural disintegration occurs. The instability of ZFO-BTO ME CSNPs is attributed to nonuniform interfacial strain, low ZnFe₂O₄ core magnetostriction, and a suboptimal core-to-shell thickness ratio. PFM switching studies reveal 90° domain polarization in the BaTiO₃ shell. These findings provide valuable insights into the design of novel core-shell nanocomposites with enhanced magnetoelectric coupling and structural stability.

Zinc-ion batteries (ZIBs) are emerging battery technology considered one of the most competitive alternatives to conventional batteries. However, their development demands strategic techniques to resolve the main drawbacks of their active electrodes, which caused structural instability and poor electrochemical performance in the long run. Atomic layer deposition (ALD) is a thin film coating technique boasting its capability for a uniform, precise, and controllable atomic-level deposition of functional materials. Due to these characteristics, several studies harnessed ALD for ZIB fabrication. Understanding the current narrative of ALD in ZIB development is indispensable to realize new perspectives for its progression in the field. Hence, this review provides an overview of the narrative of ALD in energy storage systems such as ZIBs. The discussion revolves around its fundamental principles, current applications, advancements, and the challenges with ALD. This review concludes by underscoring the essential prospects and perspectives for the future application of ALD for ZIB development.

In this study, a facile and fast aqueous-phase synthetic method for preparing chitosan-based fluorescent nanogels (CS) by exploiting the aggregation-induced emission (AIE) property of copper nanoclusters (Cu NCs) is proposed. Owing to the spatial confinement provided by the crosslinking network structure in chitosan-based nanogels and the electrostatic interaction between positively charged chitosan nanogels and negatively charged Cu NCs, the fluorescent intensity of the as-prepared CS-Cu NCs was increased by approximately 17-fold compared with that of Cu NCs. The fluorescence quantum yield is increased by more than four times; the as-prepared CS-Cu NCs exhibited a quantum yield of 64.12%. Additionally, CS-Cu NCs exhibited significantly improved stability in aqueous solution, including excellent oxidation resistance, high anti-salt stability, good thermal stability, and enhanced capacity of anti-photobleaching. These properties provide a fundamental guarantee for the application of Cu NCs with AIE property in the biosensor and bioimaging. Upon the addition of the anticancer drug methotrexate (MTX) to CS-Cu NCs, their fluorescent intensity was markedly quenched. Based on the observed fluorescence-quenching phenomenon of CS-Cu NCs induced by MTX, a novel fluorescence quenching nanoprobe was designed for detecting the labeling amount percentage of commercially available methotrexate tablets. The experimental results validated that our proposed nanoprobe exhibits a wider dynamic linear range and excellent accuracy with a low limit of detection (LOD) of 4.16 μM, thereby expanding the potential application of chitosan-based nanogels encapsulating metal nanoclusters presenting AIE property in pharmaceutical quality control.

In this study, PCB 138 was chosen to evaluate the impact of photodegradation using newly synthesized ZnO-SO₃H nano semiconductor in the presence of visible light in aqueous solutions. This study focused on the preparation of the ZnO-SO₃H nano photocatalyst. The structures of the nano photocatalysts were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and N₂ adsorption–desorption isotherm analyses. In this study, the effects of the catalyst dose, the zero-charge point, solution pH, and the initial PCB 138 concentration were investigated. FESEM, TEM, and XRD results of the ZnO-SO₃H nano photocatalyst showed that ZnO in the presence of ClSO₃H has changed to a layered and rod structure. Also, the nitrogen adsorption–desorption isotherm has shown that ClSO₃H has changed the structure of commercial ZnO. Based on the results of experiments in batch-mode photoreactor, the optimum amount of the ZnO-SO₃H nano photocatalyst, solution pH, and initial concentration of PCB 138 was 2.5 g/L, 7.2, and 2 ppm, respectively. The photodegradation efficiency of PCB 138 after 1 h with the ZnO-SO₃H nano semiconductor was 78.55, which had a higher efficiency than commercial ZnO.

Tumor markers, produced due to genetic alterations, are vital for cancer detection, diagnosis, treatment, and prognosis. Quantum dots (QDs), a novel luminescent nanomaterial, exhibit unique chemical and optical properties. Integrating QDs with biosensing technology enables highly sensitive and selective detection of target molecules, offering significant potential in biomedicine. This study developed a g-CNQDs-Apt/WS₂/Fe₃O₄ magnetically separated fluorescent aptasensor based on fluorescence resonance energy transfer (FRET) for detecting the tumor marker mucin 1 (MUC1). Magnetic separation enhanced fluorescence recovery, reduced background interference, and improved the linear detection range for MUC1. The system demonstrated a strong linear correlation (R² = 0.9926) between MUC1 concentration and fluorescence recovery, with a detection limit of 0.89 ng/mL, relative standard deviations of 3.24%–4.68%, and recoveries of 94.99%–112.39%. These findings provide valuable insights for developing fluorescent aptasensors for other tumor markers and biomedical targets.