Search Results (697)

Electromagnetic wave interference has escalated into a pervasive global issue, driving intensified research efforts across both civilian and military domains. However, the development of advanced electromagnetic wave (EMW) absorbers with finely tunable dielectric and magnetic loss properties has emerged as a pivotal strategy for mitigating electromagnetic pollution. Herein, we propose a cation engineering strategy to tailor the absorption properties of ZIF-67-derived layered double hydroxide (LDH) composites through systematic substitution of Co²⁺ with Fe, Mn, Zn, or Ni and stoichiometric control (Co/X = 1:4, 1:1). Mn/Zn doping enhances dipole polarization via lattice distortion, while structural analysis confirms that higher Co/X ratios preserve core–shell architectures, optimizing impedance matching. In contrast, Fe incorporation leads to excessive conductivity and impedance mismatch. The optimized CoNi1-4 composite exhibits superior broadband absorption (EAB = 4.52 GHz at 1.8 mm thickness, RL_min = −24.5 dB), attributed to synergistic interface polarization and magnetic coupling. This study delivers a highly tailorable materials platform that enables a deeper fundamental understanding of the synergy between dielectric and magnetic loss processes, thereby offering new pathways for optimizing electromagnetic wave absorption. Full article

Zeolitic imidazolate frameworks (ZIFs) can provide fascinating stereo morphology and tunable metal active sites, which plays an important role in the synthesis of various catalytic materials. However, it is still a problem to make use of these advantages to design efficient hydrogen evolution reaction (HER) catalysts. Herein, we use covalent coordination strategy to synthesize bimetallic Co_xZn_1−x(2-MeIM)₂ precursors with regular dodecahedral structures for providing uniform active sites and stable carbon skeleton. Furthermore, the ratio of Co and Zn atoms was optimized to balance the electron density and give full play to the synergistic catalytic effect. And then, the subsequent high temperature annealing process is used to construct the amorphous carbon layer, which can improve the overall stability of the material. The gas phase phosphating process realizes the transformation from ZIF material to metal phosphide resulting in enhanced hydrogen evolution activity. Finally, the optimized amorphous nitrogen-doped carbon (NC)-coated Zinc-doped cobalt phosphide (Zn_0.17Co_0.83P@NC) requires only 237.60 mV to reach the current density of 10 mA cm⁻² in alkaline medium, which is 223.22 mV lower than that of CoP, and has a stability of up to 18 h. This work provides a reference for the rational design of efficient and stable compound electrocatalysts for alkaline hydrogen evolution based on the bimetallic ZIF as a precursor. Full article

Green nanotechnology offers a sustainable and eco-friendly approach for nanoframework synthesis. The present study intended to synthesize a novel eco-friendly encapsulated Zeolitic Imidazolate Framework-8 (ZIF-8) in a one-pot method using metabolites from the mangrove plant Conocarpus erectus (CE). Gas Chromatography–Mass Spectrometry (GC-MS) analysis of the extract revealed the presence of important bioactive metabolites. The synthesized material was evaluated by UV-Vis spectroscopy, X-ray diffraction (XRD), particle size analysis (PSA), zeta potential measurement, high-resolution transmission electron microscopy (HR-TEM), and Fourier transform infrared (FT-IR) spectroscopy studies. The environment-friendly mangrove metabolites aided by Zeolitic Imidazolate Framework-8 was found to be crystalline, rhombic dodecahedron structured, and size dispersed without agglomeration. The nanomaterial possessed a broad antimicrobial effect on drug-resistant microorganisms, including Candida krusei, Escherichia coli, Streptococcus Sp., Staphylococcus aureus, Enterococcus Sp., Pseudomonas aeruginosa, Klebsiella pneumoniae, C. propicalis, and C. albicans. Further, its cytotoxicity against MDA-MB-231 cells was found to be efficient. The morphological alterations exhibited by the antiproliferative impact on the breast cancer cell line were detected using DAPI and AO/EB staining. Therefore, ZIF-8 encapsulated mangrove metabolites could serve as an effective biomaterial with biomedical properties in the future. Full article

Background/Objectives: A non-toxic nano-platform which can increase drug-loading rate and synergistically increase antitumor effect is very ideal. This study provides the concept that a combination of photothermal therapy with chemotherapy and anti-inflammatory therapy will be achieved by ablation of the local tumor, robust strategies for the suppression of distant tumors with enhanced antitumor therapy outcomes. Methods: In this study, the chemotherapeutic drug cisplatin (DDP) and the anti-inflammatory drug Aspirin-DL-Lysine (ADL) were loaded into a hollow porous nanomaterial zeolitic imidazolate framework-8 (ZIF-8), which was then coated with polydopamine, in order to form near-infrared absorption organic nanoparticles DDP-ADL@ZIF-8@PDA with excellent photothermal conversion efficiency. The antitumor efficacy of the nanodrug was evaluated through physicochemical characterization, cell biology studies, and animal experiments. Results: Photothermal therapy (PTT) of polydopamine combined with DDP and ADL can reduce inflammation and the immunosuppressive tumor microenvironment, and enhance antitumor effect. The results showed that the combined therapy could effectively eliminate the primary tumor, shrink the distant tumor, and inhibit the metastasis of the tumor. PTT in combination with chemotherapy and anti-inflammatory therapy can inhibit the expression of inflammatory factors, significantly reducing tumor immunosuppression by eliminating bone marrow-derived suppressor cells and increasing levels of cytotoxic T lymphocyte. Conclusions: This study successfully developed a DDP-ADL@ZIF-8@PDA nanomedicine for effective drug delivery, synergistic photothermal therapy, and anti-inflammatory attenuated immunotherapy to enhance treatment of human cervical cancer xenografts in mice. Overall, the combination of photothermal therapy with chemotherapy and anti-inflammatory therapy on a nano-platform has great potential for antitumor therapy applications. Full article

The quality and safety of agricultural products are important factors in safeguarding human health and promoting sustainable agricultural development. However, for the purpose of improving the yield and quality, the misuse of pesticides often occurs, causing pesticide residues to remain in vegetables, posing threats to both the environment and human health. In order to detect and adsorb pesticide residues in vegetables, a coral-like novel magnetic porous nanomaterial (Fe@MDZ) was developed in this study as an adsorbent to adsorb thiabendazole (TBZ). Fe@MDZ has a large specific surface area (229.254 m²/g) and high saturation magnetization intensity (57.38 emu/g) with good adsorption capacity for TBZ. When the initial concentration was 2 mg/L, the adsorption capacity for TBZ was 1.23 mg/g. The static adsorption process matched the Langmuir isotherm model and was consistent with the pseudo-second-order kinetic model. In addition, the recovery of TBZ in both tomato and Chinese cabbage samples at different concentrations was above 70%. This work provides a new idea for the detection of TBZ pesticide residues in vegetables. Full article

The use of chemical fungicides in agriculture has led to the need for more efficient and sustainable solutions. Controlled-release nanomaterials offer a promising approach by improving fungicide delivery and reducing the need for frequent applications. This study investigates the synthesis of a dual-responsive nanofungicide through the loading of carbendazim (MBC) into zeolitic imidazolate framework-8 (ZIF-8), etching with tannic acid (TA) and the introduction of pectin (PT) to synthesize the MBC@ZTA-PT. The pectin, which was extracted from sweet potato peels, was applied as an eco-friendly, biodegradable additive that enhanced the stability and controlled-release properties of nanofungicide. Tannic acid etching significantly improved MBC loading efficiency. The cumulative release rates after 96 h under three different conditions were 33.12% at pH 7, 59.00% at pH 7 with the addition of pectinase, and 70.74% at pH 5 with the addition of pectinase, highlighting the strong responsiveness of the nanofungicide to pH and enzyme triggers. This dual-response system provided controlled release, thereby enhancing MBC utilization efficiency and minimizing the environmental hazards associated with fungicide applications. The findings suggest that MBC@ZTA-PT represents a promising, environmentally friendly strategy for sustainable plant disease management. Full article

Background/Objectives: Primary dysmenorrhea is a prevalent condition that causes severe uterine cramps in women worldwide. The objective of this work was to synthesize and characterize a novel immediate-release system using vitexin and ZIF-8, and to evaluate its pharmacological action in a model of primary dysmenorrhea. Methods: A 2² full factorial design guided the synthesis of the system. Physicochemical characterization was performed by FT-IR, TG, DSC, SEM, XRD, and in vitro release tests. Pharmacological activity was assessed in an oxytocin-induced dysmenorrhea model in mice. In addition, in silico molecular docking and molecular dynamics simulations were conducted to explore the potential mechanism of action of vitexin. Results: Optimal yield and loading capacity were achieved at the high levels of the factorial design. Characterization analyses confirmed the successful formation of the vitexin@ZIF-8 (VIT@ZIF-8) system. The release study demonstrated a markedly enhanced dissolution rate of vitexin. Both isolated vitexin and VIT@ZIF-8 reduced abdominal writhing when administered orally at 3 and 30 mg/kg, while intraperitoneal activity was observed only at 30 mg/kg. Computational analyses revealed favorable interactions of vitexin with aldose reductase (AKR1C3), suggesting this enzyme as a potential molecular target in dysmenorrhea. Conclusions: The VIT@ZIF-8 system represents a promising strategy to improve the dissolution profile of vitexin, although pharmacological activity in this model was not superior to the isolated compound. The combined in vivo and in silico evidence supports vitexin as a potential antidysmenorrheic agent, possibly through modulation of AKR1C3. These findings open avenues for future studies addressing the molecular pathways of vitexin and for the development of novel therapeutic approaches for primary dysmenorrhea. Full article

The interfacial properties in carbon fiber (CF)-reinforced polymer composites are substantially limited by the chemically inactive and smooth CF surfaces. In this study, zeolitic imidazolate framework 90 (ZIF90) was chemically grafted onto CF surfaces via polyethyleneimine (PEI) as a coupling agent to construct a hierarchical reinforcement interface in CF/epoxy composite. The successful synthesis of CF grafted with PEI and ZIF90 (CF-PEI-ZIF90) was systematically characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The incorporation of ZIF90 nanocrystals and PEI molecules into CF surfaces effectively improved interfacial adhesion through mechanical interlocking and chemical interactions, thereby optimizing stress transfer efficiency at the fiber–matrix interface and improving the interfacial properties of the composite. Additionally, the resultant CF-PEI-ZIF90/epoxy composite demonstrated significant mechanical enhancement, with the tensile and bending strengths increasing by 33.5% and 21.4%, respectively, compared to unmodified CF/epoxy composites. This work provides a novel strategy for enhancing the interfacial performance of CF composites by leveraging the unique properties of metal-organic frameworks, which is critical for advancing high-performance structural materials in aerospace and automotive applications. Full article

Volatile organic compound (VOC) monitoring is crucial for environmental safety and health, but conventional gas sensors often suffer from poor selectivity or lack spatial information. Here, we report a localized surface plasmon resonance (LSPR) gas sensor based on Au nano-urchins coated with a zeolitic imidazolate framework (ZIF-8) for both the quantitative detection and visualization of VOCs. Substrates were fabricated by immobilizing Au nano-urchins (~90 nm) on 3-aminopropyltriethoxysilane-modified glass and subsequently growing ZIF-8 crystals (~250 nm) for different durations. Scanning electron microscopy and optical analysis revealed that 90 min of ZIF-8 growth provided the optimal coverage and strongest plasmonic response. Using a spectrometer-based LSPR system, the optimized substrate exhibited clear, concentration-dependent responses to three representative VOCs, 2-pentanone, acetic acid, and ethyl acetate, over nine concentrations, with detection limits of 12.7, 14.5, and 36.3 ppm, respectively. Furthermore, a camera-based LSPR visualization platform enabled real-time imaging of gas plumes and evaporation-driven diffusion, with differential pseudo-color mapping providing intuitive spatial distributions and concentration dependence. These results demonstrate that ZIF-8-modified Au nano-urchin substrates enable sensitive and reproducible VOC detection and, importantly, transform plasmonic sensing into a visual modality, offering new opportunities for integrated LSPR–surface-enhanced Raman scattering dual-mode gas sensing in the future. Full article

Periodontitis is a chronic oral inflammatory disease whose treatment is often hindered by poor drug retention, prolonged therapeutic regimens, and the rise of antibiotic resistance. In this study, we developed a Hydrogel@ZIF-8@metronidazole (Hydrogel@ZIF-8@MNZ) nanocomposite dressing for targeted, sustained, and in situ antimicrobial therapy. This system integrates ZIF-8, a pH-responsive metal–organic framework, with the antimicrobial agent metronidazole (MNZ), encapsulated within a crosslinked hydrogel matrix to enhance stability and retention in the oral environment. Drug release studies demonstrated that MNZ release was significantly accelerated under acidic conditions (pH 5.0), mimicking the periodontal microenvironment. The Hydrogel@ZIF-8 composite achieved a maximum MNZ adsorption capacity of 132.45 mg·g⁻¹, with a spontaneous and exothermic uptake process best described by a pseudo-second-order kinetic model, suggesting chemisorption as the dominant mechanism. The nanoplatform exhibited strong pH-responsive behavior, with enhanced drug release under acidic conditions and potent dose-dependent bactericidal activity against Fusobacterium nucleatum (Fn). At the highest tested concentration, bacterial survival was reduced to approximately 30%, with extensive membrane disruption observed through live/dead fluorescence microscopy. In summary, the stimuli-responsive Hydrogel@ZIF-8@MNZ nanocomposite offers an intelligent and effective therapeutic strategy for periodontitis. By tailoring its action to the disease microenvironment, this platform enables sustained and localized antibacterial therapy, addressing major challenges in the treatment of chronic oral infections. Full article

Wider adoption of membrane technology is hindered by fouling and flux/rejection challenges. Recent practice in mitigating these is to incorporate hydrophilic and porous fillers. Herein the addition of hydrophilic graphene oxide (GO) in conjunction with porous mixed ZIFs (ZIF-67/ZIF-8) crystallites were used as inorganic fillers in the preparation of polyphenylenesulfone (PPSU) ultrafiltration (UF) membranes. The morphology of the resultant composite membranes was assessed using atomic force microscopy (AFM) and scanning electron microscopy (SEM) whilst surface hydrophilicity through water contact angle. The pure water flux (PWF) and membrane permeability were found to increase with increasing filler content. This was attributed to the combined hydrophilicity of GO and porous structure of the ZIF materials because of increasing alternative water pathways in the membrane matrix with increasing filler content. Furthermore, the increase in the ZIF component led to increasing bovine serum albumin (BSA) fouling resistance as demonstrated by increasing fouling recovery ratio (FRR). The dye rejection was due to a combination of electrostatic interaction between the fillers and the dyes as well as size exclusion. The chemical interactions between the ZIFs and the dyes resulted in slightly different rejection profiles for the smaller dyes, the cationic methylene blue being rejected less efficiently than the anionic methyl orange, potentially leading to their separation. The larger anionic dye, Congo red was rejected predominately through size exclusion. Full article

Chitosan biopolymer membranes reinforced with channel-selective ZIF-8 nanofillers were developed and thoroughly characterized as separators for bioelectrochemical systems. This study explores the synergistic effect of incorporating ZIF-8 into a chitosan matrix to enhance membrane performance. Key properties including water retention, chemical and thermal stability, surface resistance, antifouling capacity, and ionic conductivity were evaluated and benchmarked against commercial Nafion-117 and nanofiltration (NF) membranes. The ZIF-8/chitosan composite membranes (ZIF-8/CS) demonstrated excellent water retention and structural stability under harsh conditions, along with significantly reduced surface resistance and effective rejection of organic contaminants and salts (NaCl, Na₂SO₄). Notably, the composite ZIF-8/CS membranes achieved an ionic conductivity of 0.099 S/cm, approaching the value of Nafion-117 (0.13 S/cm) and substantially surpassing that of the NF membrane (0.013 S/cm). These results indicate that ZIF-8-reinforced chitosan membranes present a promising, sustainable, and cost-effective alternative to traditional separators in bioelectrochemical applications. Full article

The widespread contamination of aquatic systems by ciprofloxacin (CIP)—a persistent fluoroquinolone antibiotic—poses severe ecological risks due to its antibacterial resistance induction. Conventional sulfate radical-based advanced oxidation processes (SR-AOPs) suffer from inefficient catalyst synthesis, exemplified by low-yield ZIF-67 precursors (typically <25%). To address this, a nitrogen-doped carbon composite Co₃O₄/N@C was synthesized via ammonia-assisted ligand exchange followed by pyrolysis, using N-doped ZIF-67 as a self-sacrificial template. The ammonia incorporation quadrupled precursor yield compared to ammonia-free methods. This catalyst activated peroxydisulfate (PDS) to degrade 95% CIP within 90 min under the optimized conditions (0.5 g/L catalyst, 2 mmol/L PDS, pH 5), representing a 30% enhancement over non-ammonia analogs. Mechanistic studies identified singlet oxygen (¹O₂) as the dominant reactive species, facilitated by N-doped carbon-mediated electron transfer. This strategy overcomes the scalability barrier of MOF-derived catalysts for practical antibiotic wastewater remediation. Full article

This study presents a pH-responsive drug delivery platform, created based on naproxen-loaded zeolitic imidazolate frameworks (ZIF) and kaolin-ZIF (Kao@ZIF) nanocarriers embedded in a 3D-printed polylactic acid (PLA) scaffold coated with a gelatin hydrogel. The PLA discs were designed as structural tissue models to simulate localized drug release. Kaolin (Kao), a basic mineral in the kaolin group that includes halloysite, was selected as a chemically stable and biocompatible adsorbent to enhance ZIF integrity and system reliability. To address the concerns about the safety and reproducibility of nanoscale materials in biomedical applications, structurally stable ZIF and Kao@ZIF nanocarriers were synthesized and characterized using FT-IR, SEM-EDS, and LC-M/MS, measuring drug loading efficiencies over 90% for ZIF and slightly higher for Kao@ZIF. In vitro release profiles showed strong pH sensitivity, with greater naproxen release at acidic pH (5.4) and more sustained release from Kao@ZIF. Cytotoxicity assays using L929 fibroblasts demonstrated improved biocompatibility, with cell viabilities of approximately 75% for ZIF–naproxen, 82% for Kao@ZIF–naproxen, and 90% for gelatin-coated PLA–Kao@ZIF scaffolds, for 24 h incubation. Incorporating kaolin-stabilized ZIF nanocarriers into 3D-printed biodegradable scaffolds offers a promising and safer approach for pH-sensitive, tissue-targeted drug delivery, while laying the groundwork for future studies involving halloysite-derived nanotubular systems. Full article

The inherent hydrophobicity of poly(vinylidene fluoride) (PVDF) ultrafiltration membranes leads to severe membrane fouling when processing proteinaceous solutions and organic contaminants, significantly limiting their practical applications. This study presents a novel metal-ion mediated co-deposition strategy for fabricating high-performance antifouling poly(vinylidene fluoride) (PVDF) hollow fiber ultrafiltration membranes. Through Zn²⁺ coordination-driven self-assembly, a uniform and stable composite coating of dopamine (DA), tannic acid (TA), and ZIF-8 nanoparticles was successfully constructed on the membrane surface under mild conditions. The modified membrane exhibited significantly enhanced hydrophilicity, with a water contact angle of 21° and zeta potential of −29.68 mV, facilitating the formation of a dense hydration layer that effectively prevented protein adhesion. The membrane demonstrated exceptional separation performance, achieving a pure water permeability of 771 L/(m²∙h∙bar) and bovine serum albumin (BSA) rejection of 97.7%. Furthermore, it showed outstanding antifouling capability with flux recovery rates exceeding 83.6%, 74.7%, and 71.5% after fouling by BSA, lysozyme, and ovalbumin, respectively. xDLVO analysis revealed substantially increased interfacial free energy and stronger repulsive interactions between the modified surface and protein foulants. The antifouling mechanism was attributed to the synergistic effects of hydration layer formation, optimized pore structure, additional water transport pathways from ZIF-8 incorporation, and electrostatic repulsion from negatively charged surface groups. This work provides valuable insights into the rational design of high-performance antifouling membranes for sustainable water treatment and protein separation applications. Full article