Search Results (1,214)

This in vitro study evaluated the effects of simulated gastric acid exposure on surface roughness, color change, translucency, and mass change in four monolithic CAD/CAM restorative materials with different microstructural compositions. Rectangular specimens (12 × 14 × 1 mm; n = 12/group) were prepared from a polymer-infiltrated ceramic network material (VITA Enamic), a zirconia-reinforced lithium silicate glass-ceramic (Celtra Duo), a resin nanoceramic (Cerasmart), and a lithium disilicate glass-ceramic (IPS e.max CAD). After standardized finishing and polishing, baseline measurements of surface roughness, color coordinates, translucency, and mass were obtained, and the specimens were then individually immersed in simulated gastric acid (0.06 M HCl, pH 1.2) at 37 °C for 96 h, with the solution renewed every 24 h. Post-exposure measurements were performed using the same protocols. Data were analyzed using the Shapiro–Wilk test, Kruskal–Wallis test with Dunn’s post hoc comparisons, and Wilcoxon signed-rank test (α = 0.05). Significant changes were observed after acid exposure, and the magnitude of these changes varied among materials. Surface roughness increased significantly in all groups, with the greatest increase detected in Celtra Duo and VITA Enamic. Measured mass also changed significantly in all groups; VITA Enamic showed a slight increase, whereas Celtra Duo, Cerasmart, and IPS e.max CAD showed slight decreases. Although statistically significant differences in color change and translucency were identified among the groups, all color changes remained below the clinically perceptible threshold, indicating limited optical impact under the present model. IPS e.max CAD exhibited the lowest color change, whereas Cerasmart showed the highest ΔE00 values. Within the limitations of this accelerated in vitro model, simulated gastric acid exposure caused material-dependent alterations in surface roughness, limited optical changes, and small measured mass changes in monolithic CAD/CAM restorative materials. Full article

Given the widespread contamination of water bodies by diverse pollutants, particularly heavy metal ions and organic dyes, there is an urgent need to develop efficient and sustainable biomass adsorbents. Lignin is rich in active groups such as phenolic hydroxyl and carboxyl groups, making it a natural adsorbent. However, its application is still hindered by limitations, including restricted solubility and low reactivity. Converting lignin into three-dimensional porous hydrogels not only overcomes the inherent structural brittleness of lignin-based materials but also accelerates the diffusion kinetics of pollutants through well-developed pore structures, thereby fully exposing the active adsorption sites. This paper systematically reviews the latest progress in lignin-based hydrogels for water treatment and discusses in depth the underlying logic of “structure construction–micromorphology–adsorption performance.” First, this review summarizes synthesis strategies ranging from molecular-level modification to morphology regulation, including nano-reinforcement, magnetic functionalization, and interpenetrating polymer networks. It then provides a pollutant-specific analysis of the adsorption mechanisms of lignin-based adsorbents. For heavy metal ions, such as Pb²⁺ and Cr(VI), removal is mainly associated with coordination/complexation, ion exchange, and redox reactions. For typical organic dyes, adsorption is primarily driven by π–π interactions, hydrogen bonding, and electrostatic attraction. The effects of environmental factors, such as pH, are also systematically discussed. Finally, considering current challenges related to mechanical strength, regeneration performance, and practical application, this review outlines future research directions for the development of multifunctional, integrated, and stimuli-responsive lignin-based adsorbents. Full article

Over the past two decades, triphenylamine (TPA)-based supramolecular coordination metallacycles, constructed by incorporating TPA and its derivatives as key building blocks into two-dimensional (2D) coordination-driven assemblies, have gradually received considerable attention and emerged as an important research topic within the field of discrete supramolecular coordination complexes (SCCs). Leveraging the synthetic accessibility and outstanding optoelectronic properties of TPA units, the resulting TPA-based metallacycles exhibit well-defined topological structures, excellent emission characteristics, and unique functions. In this review, we systematically and comprehensively discuss the design strategies, synthetic methodologies, and practical applications for TPA-based supramolecular metallacycles, with an emphasis on five key aspects: (i) coordination-driven self-assembly, (ii) hierarchical self-assembly, (iii) supramolecular polymers, (iv) tunable fluorescence, and (v) diverse applications. Finally, future perspectives and challenges in this rapidly evolving field are presented. Full article

It is crucial to develop advanced fluorescence sensing platforms for precise detection of metal pollutants in environmental monitoring. However, traditional fluorescent probes are often limited by aggregation-caused quenching (ACQ). In contrast, clusterization-triggered emission (CTE) probes, based on non-conjugated systems, exhibit excellent photostability by relying on spatial clusterization to restrict molecular motion. Crab shells, an abundant aquatic waste, are rich in chitin (20–30%). Following deacetylation, chitin is converted into chitosan, a biocompatible and biodegradable biopolymer with excellent potential for chemical modification. In this study, a novel chitosan-based CTE fluorescent probe (CS-FA) was synthesized via a facile cross-linking condensation reaction between chitosan and formaldehyde. This process successfully restricts intramolecular motion and promotes the tight clustering of electron-rich heteroatoms, thereby activating the CTE mechanism. The resultant CS-FA probe exhibits strong and stable blue fluorescence and demonstrates high selectivity and sensitivity toward Fe³⁺ in aqueous media. In the concentration range of 10–100 µM, the fluorescence intensity decreases linearly with the Fe³⁺ concentration, yielding a competitive limit of detection (LOD) of 0.52 µM. Mechanistically, the specific coordination between Fe³⁺ and the cross-linked polymer provides a dominant non-radiative decay pathway, leading to significant fluorescence quenching. Ultimately, this work not only proposes an innovative strategy for constructing sensitive and biomass-derived probes for Fe³⁺ monitoring but also broadens the high-value utilization pathways of marine waste, thereby providing a sustainable waste-to-resource strategy. Full article

Two novel multi-layer three-dimensional polymers (Polymer 1 and Polymer 2) were designed and synthesized via a multi-step coupling strategy. Their photophysical properties, aggregation-induced emission (AIE) behaviors, and metal ion sensing capabilities were systematically investigated. Both polymers exhibited typical aggregation-induced emission (AIE) characteristics with significantly enhanced fluorescence upon aggregation in tetrahydrofuran (THF)/water mixtures. Polymer 1 demonstrated selective and sensitive detection of Ag⁺ ions with a detection limit of 2.14 μM, while Polymer 2 showed exceptional recognition toward Ba²⁺ ions with a detection limit of 6.42 μM. Competitive experiments confirmed their good selectivity even in the presence of interfering metal ions. The distinct sensing behaviors were attributed to the different coordination environments provided by the polymer backbones. This work expands the family of multi-layer three-dimensional AIE-active polymers and demonstrates their utility as fluorescent probes for the detection of silver and barium ions. Full article

Poly(ethylene oxide) (PEO)-based solid polymer electrolytes are regarded as highly promising solid electrolyte materials owing to their favorable chain flexibility. However, their practical application is hindered by low room-temperature ionic conductivity and poor mechanical properties. To address these issues, a metal–organic framework (Cu-MOF) with a 2D layered structure and 1D microchannels is introduced into PEO to form a composite solid electrolyte. The results reveal that Cu-MOF can suppress PEO crystallization through steric hindrance and coordination interactions, thereby increasing the fraction of the amorphous phase. Moreover, its unsaturated metal sites can attract TFSI⁻ anions, promoting the dissociation of the sodium salt and enhancing sodium-ion transport. Theoretical calculations and molecular simulations further confirm the regulatory role of Cu-MOF in ion transport. Leveraging this mechanism, the Na₃V₂(PO₄)₃/C|PCM-8%|Na cell delivers exceptional electrochemical performance over a wide temperature range. At room temperature, the capacity exhibits virtually no decay after 200 cycles at 0.5 C, and outstanding rate capability is maintained even at a high rate of 4 C. At a temperature of 65 °C, a capacity retention of 91.4% is achieved after 200 cycles at 0.5 C. This study offers a highly promising strategy for the development of wide-temperature-range, high-performance solid-state sodium batteries. Full article

Synthetic dyes such as Methyl Orange (MO) and Congo Red (CR) are recalcitrant, toxic, mutagenic and resistant to conventional biodegradation, and their industrial discharge continues to contaminate aqueous ecosystems worldwide. This study reports the synthesis and characterization of a poly(MMA-co-2-AEMA) copolymer gel (Fe-Copolymergel-NH₂) treated with FeCl₃. It evaluates its adsorption performance from aqueous solution against the anionic azo dyes MO and CR. Extensive characterization using N₂ adsorption–desorption at 77 K, FTIR-ATR, XPS, SEM, and TEM revealed that Fe modification significantly improved the material’s textural properties, increasing its specific surface area from 8.11 m²/g to 12.55 m²/g and creating a highly irregular, interconnected, sponge-like morphology. Adsorption experiments showed that Fe-Copolymergel-NH₂ achieved competitive Langmuir maximum monolayer adsorption capacities of 3201.9 mg/g for CR and 1089.8 mg/g for MO. Kinetic modeling demonstrated that adsorption strictly followed the PSO model, primarily governed by chemisorption via electrostatic attractions and complexation within the internal structure at Fe³⁺ coordination centers. Thermodynamic analysis revealed that the dye removal process was spontaneous and exothermic. Consequently, the successful integration of Fe³⁺ coordination centers resolves the adsorption and structural limitations of pure polymer matrices, positioning Fe-Copolymergel-NH₂ as a highly promising and efficient adsorbent for the remediation of dye-contaminated industrial wastewater. Full article

Bio-based origin, biodegradability, and compostability represent distinct concepts, and promising laboratory results do not always translate biopolymer-based food packaging into industrial implementation. This review adopts a value-chain perspective to critically assess the transition of biopolymer-based food packaging from renewable feedstocks to commercial products and end-of-life management. It evaluates key stages of the entire value chain, including polymer production, processing technologies, economic feasibility, regulatory requirements, environmental performance, and waste-management strategies. Major barriers to commercialization include feedstock and material variability, production and purification costs, processing limitations, performance gaps, certification challenges, and insufficient recycling or composting infrastructure. Evidence from techno-economic and life cycle assessments indicate that successful implementation depends on integrated production systems, process optimization, co-product valorization, and realistic end-of-life scenarios. Advancing biopolymer packaging therefore requires coordinated development across the entire value chain rather than isolated improvements in polymer design. Full article

Background. Gout is an inflammatory disease caused by the deposition of monosodium urate (MSU) crystals, leading to reactive oxygen species (ROS) production and activation of the NLRP3 inflammasome with subsequent IL-1β release. Poly-gallic acid (PGAL), enzymatically synthesized polymer, has demonstrated antioxidant and anti-inflammatory properties; however, its effect on MSU-induced inflammasome activation remains unclear. Thus, this work aims to evaluate the effect of PGAL on oxidative stress and inflammatory responses induced by MSU crystals in THP-1-derived macrophages. Methods. Macrophages were pretreated with PGAL and stimulated with MSU crystals. Cell viability, apoptosis, phagocytosis, ROS and NO production, soluble urate levels, and NLRP3 and IL-1β expression were evaluated. Molecular docking and binding free energy calculations were performed to characterize PGAL–MSU interactions. Results. PGAL significantly reduced ROS and NO production, and apoptosis. PGAL treatment also decreased MSU crystal phagocytosis and significantly reduced NLRP3 and IL-1β. Computational analysis revealed that PGAL interacts with MSU crystals predominantly through electrostatic interactions, including Na⁺ coordination and hydrogen bonding. Conclusions. PGAL attenuates MSU-induced oxidative stress and NLRP3/IL-1β activation, possibly by interfering with crystal internalization. These findings suggest a mechanism based on modulation of crystal–cell interactions and downstream inflammation responses. Full article

Material Extrusion (MEX) additive manufacturing (AM) of ABS polymer components often requires post-process machining to achieve the necessary dimensional precision and surface quality. However, the influence of printing parameters and tool–material interaction in hybrid manufacturing remains insufficiently explored. This study investigates the impact of initial hole size (D_start), build orientation, and cutting parameters (cutting speed and feed rate) on the dimensional accuracy and surface roughness of machined holes in ABS-M30 specimens. Samples were fabricated in vertical and horizontal orientations and subjected to drilling in solid material and enlargement of printed pilot holes using a twist drill on a 5-axis machining center. Dimensional deviation and surface roughness (Ra, Rz) were evaluated using coordinate metrology and profilometry. The results showed that the smallest machining allowance (0.062 mm per side) was insufficient to completely remove the printing-induced surface texture, resulting in significantly higher and more variable Ra and Rz values. This distinct low-machining-allowance regime was confirmed by statistical analysis and representative optical observations. Conversely, a machining allowance of 0.565 mm per side (corresponding to D_start = 9 mm) resulted in substantially lower surface roughness (Ra ≈ 1.6 µm). Vertical build orientation generally provided better surface quality than the horizontal orientation, which was consistent with fewer visible surface features in the selected optical fields of view. All machining conditions resulted in negative dimensional deviations, indicating elastic recovery of the ABS material after machining. An exploratory multi-response ranking showed that the lowest composite quality scores for overall final hole quality were associated with D_start = 10 mm (machining allowance of 0.062 mm per side). When the analysis was limited to the machining-dominated regime, the lowest score was obtained for the vertical build orientation, D_start = 9 mm, a cutting speed of 40 m/min, and a feed rate of 0.2 mm/rev. These findings provide preliminary guidelines for selecting hybrid manufacturing conditions for MEX-manufactured ABS-M30 components. Full article

Given the urgent need to regulate oxidative stress microenvironments in chronic wound healing, hydrogel dressings that simultaneously integrate antioxidant, antibacterial, mechanically adaptive, and biocompatible properties are highly desirable. In this study, a natural polymer-based composite hydrogel dressing loaded with zinc-quercetin nanozyme (Zn-Q) was designed. The gel skeleton was constructed via a dual network of photocrosslinked methacrylated silk fibroin (SilMA) and mercaptolated hyaluronic acid (HA-SH) via thiol-ene click chemistry, with the catalase (CAT)-like Zn-Q nanozyme encapsulated in situ within the network, thereby achieving synergy between chemical crosslinking and dynamic metal-polyphenol coordination. Systematic characterization revealed that Zn-Q nanozyme adopted a stable octahedral coordination configuration, and its continuous porous structure exposed abundant catalytically active sites. The composite hydrogels exhibited a highly interconnected, three-dimensional (3D) porous morphology, with swelling ratios that increased significantly with Zn-Q nanozyme content (up to around 1082%). Rheological and mechanical tests demonstrated that although incorporating the nanozyme reduced the storage modulus, the reversible physical crosslinks formed via hydrogen bonding and coordination interactions endowed the material with excellent tensile toughness and energy-dissipation capacity, exhibiting typical Mullins softening behavior. Functional evaluation showed that Zn-Q nanozyme conferred superior free radical scavenging capability to the hydrogels and exerted dose-dependent inhibition against both Staphylococcus aureus and Escherichia coli. Furthermore, the hydrogels exhibited favorable adhesion to various wet organs and heterogeneous material surfaces, with hemolysis rates below 5% and cell viability exceeding 100% after 3 days of culturing with fibroblasts, confirming their excellent hemocompatibility and cytocompatibility. This study provides an experimental basis for developing a new type of wound repair materials that integrate antioxidant, anti-infective, and mechanically adaptive properties, holding significant application potential in oxidative stress-related tissue repair fields. Full article

Luminescent sensing in aqueous media using organic small-molecule emitters is often constrained by water-induced fluorescence quenching and indicator leakage. In this study, a polymer-confined thermally activated delayed fluorescence (TADF) material, poly-BrTPPz, was synthesized by covalently copolymerizing a donor–acceptor monomer into a polyacrylamide network. Density functional theory calculations indicate spatial frontier orbital separation. The polymer matrix restricts intramolecular motion, while the polar amide microenvironment provides a solid-state solvation effect, decreasing the reverse intersystem crossing barrier to activate delayed luminescence with a lifetime of 303 μs and a photoluminescence quantum yield of 69.1% in the solid state. In aqueous environments, the material exhibits a selective quenching response toward iron(III) ions (Fe³⁺) through a mechanism involving the inner filter effect and pyrazine-coordinated static quenching. To mitigate potential secondary environmental contamination, a transmembrane diffusion model was evaluated by encapsulating the polymer within a semi-permeable membrane, which limits indicator leakage while permitting analyte permeation. This work outlines a design approach for environment-responsive luminescent devices in closed aquatic systems. Full article

This critical perspective review first classifies glyphosate-sensing platforms and then evaluates their analytical applicability to agricultural runoff. Platforms are divided at the primary level into optical and electrochemical transduction, because these families measure different physical signals and have different sources of matrix interference. They are then grouped by the process that produces selectivity or signal change: direct interaction or metal coordination, affinity recognition by aptamers, antibodies, or molecularly imprinted polymers, catalytic modulation by enzymes or nanozymes, and separation or preconcentration before detection. This hierarchy distinguishes recognition chemistry from transduction method and device configuration. The review next defines four intended analytical applications—trace surveillance, runoff event screening, spill triage, and laboratory-adjacent confirmation—and compares them in terms of matrix, target concentration range, sample preparation, reporting metrics, and quality control requirements. Glyphosate occurs in dissolved and particle-associated forms, degrades mainly to AMPA, and coexists with phosphate, glufosinate, divalent cations, natural organic matter, and suspended sediment. Consequently, the lowest reported LOD is rarely the sole criterion for selecting a method. Matrix-matched calibration, spike recovery, selectivity, response time, storage stability, reader requirements, and invalid result rules determine whether an assay is suitable for a specified analytical application. The most defensible near-term approach combines matrix-specific sample preparation, platform-specific controls, and LC-MS/MS confirmation when results are regulatory, contested, or close to a decision threshold. Full article

High-salinity waters, including seawater, brines, and saline radioactive effluents, contain recoverable uranium or require uranium removal, but their complex chemistry complicates both capture and regeneration. Under seawater-relevant conditions, U(VI) occurs mainly as uranyl carbonate complexes and ternary uranyl carbonate complexes containing Ca²⁺ or Mg²⁺ rather than as free UO₂²⁺. Selective separation therefore depends on coupled transport, hydration-shell reorganization, carbonate displacement, and interfacial coordination. Conventional sorbents largely optimize binding strength and adsorption capacity, often at the expense of harsh stripping and secondary waste. This review frames thermoresponsive uranium separation as a coupled aqueous-speciation, interfacial-state, and process-design problem. It examines how LCST and UCST transitions, polymer-brush reorganization, hydration-layer reconstruction, pore gating, and localized photothermal heating regulate access to binding sites and release pathways. Polymer brushes, hydrogels and microgels, membranes and nanochannels, ion-imprinted magnetic composites, and MXene-based hybrids are critically compared using cycle-level criteria, including U/V selectivity, switching time, regeneration demand, energy input, fouling resistance, material loss, synthesis reproducibility, and environmental performance. Particular emphasis is placed on distinguishing genuine structural gating from the generic effects of temperature on diffusion, ligand exchange, and adsorption equilibria. Current evidence supports the feasibility of programmable capture–release interfaces but remains limited by matrix-dependent transition windows, incomplete mechanistic attribution, scarce quantitative energy and temperature-gradient data, short cycling tests, and limited device-scale validation. Progress will require standardized testing in realistic saline matrices and complete capture–release mass and energy balances rather than evaluation by maximum adsorption capacity alone. Full article

Over the past three decades, pentaphosphaferrocene [Cp*Fe(η⁵-P₅)] (1*) has emerged as a versatile building block in coordination chemistry, enabling the construction of a wide range of nanosized spherical aggregates and extended coordination polymers (CPs). Previous studies have shown that modification of substituents in fully substituted cyclopentadienyl ligands strongly influences the size of the resulting spherical aggregates. However, the impact of partially substituted cyclopentadienyl ligands remains unexplored. Herein, we investigate the reactivity of the cyclo-P₅ ligands in tert-butyl-substituted pentaphosphaferrocenes [Cp^RFe(η⁵-P₅)] {Cp^R = Cp″: η⁵-1,3-(^tBu)₂C₅H₃ (1″) and Cp‴: η⁵-1,2,4-(^tBu)₂C₅H₂ (1‴)} towards Cu(I) halides (CuX; X = Cl, Br and I). These reactions yield a series of CPs (2–9) that are structurally characterized by single-crystal X-ray diffraction, multinuclear NMR spectroscopy, and ESI-MS spectrometry. Reactions of 1″ with CuCl and CuBr afford one-dimensional CPs while reactions with CuI show a pronounced dependence on stoichiometry, leading to CPs with different structural topologies and dimensionalities. In contrast, the bulkier derivative 1‴ consistently forms two-dimensional networks. These include a regular sheet-like framework (7), an architecture composed of alternating mesh sizes (8), and a distinctive double-layered structure (9) featuring Cu₄I₃ and Cu₄I₄ nodes interconnected by organometallic (1‴) and inorganic (CuI₂) linkers. Solution studies indicate partial depolymerization of the polymers, consistent with the lability of Cu-P interactions. Full article