Search Results (903)

Annulated organic molecular structures with planar, fused backbones exhibit superior properties compared to non-fused systems, including high crystallinity, strong π–π stacking, and excellent charge transport characteristics. The rational design of annulated compounds with targeted characteristics presents a significant challenge that requires a comprehensive understanding of structure–property relationships. This work addresses this by synthesizing a series of novel push–pull systems featuring benzothieno[3,2-b]benzothiophene (BT) or its nitrogen-rich analogue, indolo[3,2-b]indole (ID), as electron-donating units, connected via a phenylene π-spacer to two distinct electron-accepting groups (carbonyl or dicyanovinyl). The thermal, structural, optical and electrochemical properties of these compounds were thoroughly investigated. Computational studies of the optical and electrochemical properties, including those of unsubstituted ID and BT model cores, showed excellent agreement with experimental data, validating the theoretical models. Notably, ID-based derivatives exhibited remarkably high photoluminescence quantum yield and enhanced solubility compared to their BT counterparts, along with thermal properties that are more favorable for device fabrication. This work provides the first systematic comparison of these annulated cores, offering novel structure–property insights that may support the rational design of organic functional materials and contribute to the further development of organic electronics. Full article

Microplastics (MPs, plastic particles < 5 mm) and nanoplastics (NPs, plastic particles generally <1 µm), collectively referred to as micro/nanoplastics (MNPs), have emerged as critical contaminants in wastewater systems due to their persistence, small size, and ability to act as vectors for co-contaminants. Conventional wastewater treatment technologies are often insufficient for the effective removal of microplastics, particularly for smaller particles and nanoplastics, necessitating the development of functional materials and innovative treatment strategies. In this review, recent advances in carbon-based materials, cellulose-based materials, and their hybrid carbon–cellulose composites for microplastics removal are critically analyzed and comparatively discussed. Particular attention is given to the structure–function relationships governing adsorption performance, including the roles of hierarchical porosity, surface chemistry, and interfacial interactions. The key mechanisms responsible for microplastics capture—such as hydrophobic interactions, π–π stacking, hydrogen bonding, electrostatic attraction, physical entrapment, and pore trapping—are systematically discussed. Carbon–cellulose composite materials are highlighted as a promising class of multifunctional adsorbents due to their synergistic combination of hydrophilic cellulose scaffolds and hydrophobic carbon domains. This dual functionality enables efficient removal of microplastics across a wide range of sizes and morphologies. Recent developments in magnetic and superhydrophobic composite systems further demonstrate enhanced separation efficiency, recyclability, and potential applicability in real wastewater environments. In addition to summarizing recent progress, this review critically examines the methodological inconsistencies, mechanistic uncertainties, and practical limitations associated with current adsorption systems. Despite significant progress, several challenges remain, including the lack of standardized evaluation methods, limited validation under real wastewater conditions, material stability issues, and scalability constraints. Future research directions are proposed, focusing on rational material design, sustainable carbon sources, multifunctional hybrid systems, and integration into existing treatment infrastructures. The development of sustainable hybrid adsorption systems for microplastics remediation also contributes to the achievement of Sustainable Development Goal 6 (Clean Water and Sanitation) by supporting improved wastewater treatment technologies and reduction in emerging aquatic contaminants. Full article

We report the synthesis and single-crystal X-ray structures of three novel (Z)-5-arylidene-3-phenylrhodanine derivatives, differing in the substituents on the benzylidene fragment (two methoxy groups (compound I), a dioxine ring (compound II), or a dioxole ring (compound III)). Despite the overall similarity of the molecules, their supramolecular architectures were found out to be strikingly different. The results of intermolecular interactions in those structures are investigated via Hirshfeld surface, molecular electrostatic potential surface and non-covalent interaction analyses. The fine modulation of the arylidene substituent can switch the primary intermolecular synthon from weak S···S bonding to n···π* interactions, offering new possibilities for crystal engineering of rhodanine-based materials. Full article

The photothermal conversion capability of polydopamine (PDA) was exploited to load the anticancer drug doxorubicin (DOX) onto its surface via π-π stacking and hydrogen-bond interactions, yielding a PDA-DOX complex. In this study, biocompatible poly-L-lactic acid (PLLA) was employed as a shell material to fabricate multifunctional PLLA composite PDA-DOX (PLLA@PDA-DOX) nanobubbles with integrated functions of ultrasound imaging, photothermal therapy, and chemotherapy. The fabricated nanobubbles exhibited a uniform mean diameter of 489.30 ± 6.96 nm with a Polydispersity index (PDI) of 0.226 ± 0.01 and a DOX loading efficiency of 3.27%. Acute toxicity evaluation in mice revealed that the maximum tolerated dose of PLLA@PDA-DOX nanobubbles was markedly higher than the clinical equivalent dose, showing no detectable toxicity or allergic reactions. Under near-infrared (NIR) laser irradiation, the inhibition rate of HCCLM3 cells increased from 50.1% to 64.45%, indicating enhanced therapeutic efficacy through the combined effects of photothermal therapy and chemotherapy. Moreover, compared with the free DOX group, the survival rate of LX-2 cells in the composite nanobubble group significantly increased from 18.9 ± 1.56% to 68.8 ± 3.08%, suggesting that the PLLA@PDA-DOX nanobubbles effectively reduced the direct cytotoxicity of DOX by preventing its immediate contact with cells. Collectively, the results confirm that PLLA@PDA-DOX nanobubbles possess excellent biocompatibility, robust ultrasound imaging performance, and enhanced antitumor efficacy under NIR irradiation. This multifunctional nanosystem demonstrates promising potential as an integrated platform for simultaneous cancer diagnosis and therapy. Full article

Waste vegetable oil-based regenerants (WVO-Rs) are essential for sustainable asphalt pavements; however, their formulation optimization frameworks remain insufficient, and both the component synergy and the multi-component regeneration mechanism remain unclear. In this study, Response Surface Methodology was employed to optimize the WVO-R formulation by jointly considering the multi-temperature performance and interfacial water stability of the regenerated bitumen. Multi-scale performance tests and quantum chemical calculations were conducted to comprehensively evaluate its regeneration effectiveness and thermal behavior and to elucidate the underlying molecular mechanisms. The results indicate that the formulation optimization framework dominated by multi-temperature rheological properties and interfacial water stability exhibits superior engineering applicability compared with traditional methods, and the optimal WVO-R formulation corresponds to a mass ratio of WVO:DBP:CPR:SCA:ATO = 100:23.6:14.4:1.7:1. The WVO-R achieves optimal comprehensive regeneration at a dosage of 6–8%, exhibiting excellent thermal and storage stability along with uniform mixing. At the molecular level, the WVO-R forms a dynamic and stable molecular aggregate structure by integrating inherently stable components, leveraging the bipolar silane coupling agent to regulate critical polarity mismatches of dibutyl phthalate (DBP), and establishing a synergistic interaction network dominated by dispersion forces, supplemented by localized stacking and hydrogen-bonding interactions. On this basis, Oleic acid further depolymerizes aged asphaltene (AAS) aggregates through hydrogen bonding interactions, DBP enhances the reversible deformation capacity of AAS via π–π stacking effects, and the overall WVO-R components reshape the electronic structural characteristics of AAS to levels comparable to virgin asphaltene by smoothing the surface electrostatic potential gradient and suppressing electronic reactivity. Overall, this study establishes a systematic framework for WVO-Rs that integrates formulation optimization, regeneration performance evaluation, thermal behavior analysis, and molecular-level mechanism elucidation, thereby providing solid theoretical support for the efficient design and engineering application of bio-based bitumen regenerants. Full article

The molecular structure and magnetic properties of two conjugated polymer molecules, which have the same core of naphthalene diimide (NDI) but varying alkyl side chain lengths of 2-hexyldecyl (P(NDI2HD-T2)) and 2-octyldodecyl (P(NDI2OD-T2)), are compared. Microstructural characterizations revealed that the P(NDI2HD-T2) film exhibits a shorter π-π stacking distance and more pronounced crystalline behaviors when compared to the P(NDI2OD-T2) film. In addition, the magnetically aligned P(NDI2HD-T2) film exhibited a higher degree of chain alignment compared to the P(NDI2OD-T2) film grown using the same film preparation method. The organic field-effect transistor (OFET) based on the resulting P(NDI2HD-T2) film exhibited an average electron mobility of 1.49 cm² V⁻¹ s⁻¹, which is about a 13.5-fold enhancement compared to the spin-coat film. The findings of our study offer valuable insights into the process of magnetic manipulation, thereby offering guidelines for the rational selection of polymers to fabricate highly ordered films via the magnetic alignment method. Full article

The excessive use of herbicides in agricultural fields has emerged as a critical environmental concern. This study innovatively synthesized a ZIF-8@TPPa composite through a solvothermal method for the efficient removal of herbicides from aqueous environment. The material exhibited remarkable adsorption capacities for butachlor (232.56 mg/g), anilofos (188.68 mg/g), and pendimethalin (285.71 mg/g), along with excellent acid–base stability (pH 3–9), strong anti-ion interference capability, and good reusability (adsorption efficiency >80% after five cycles). The adsorption processes were well-described by the two isotherm models and the pseudo-second-order model, indicating that the dominant mechanism is a synergistic effect between monolayer chemical adsorption and multilayer physical adsorption, primarily driven by π-π stacking, hydrogen bonding, and coordination. The material maintained outstanding adsorption efficiency (>85%) in real water samples (tap water, seawater, and river water). This study not only provides a sustainable and effective strategy for herbicide remediation from aqueous environment but also expands the practical applications of MOF@COF in aqueous environment. Full article

In this work, three 3-carboxamidecoumarin derivatives (3b, 3c, and 4) were synthesized and characterized by NMR, IR, and single-crystal X-ray. All compounds maintain an essentially planar coumarin scaffold stabilized by an intramolecular N–H⋯O hydrogen bond (S(6) motif), though compound 4 exhibits a more complex bifurcated S₃²(11)[S(6)S(6)S(5)] network that enhances its conformational rigidity. The crystal packing analysis reveals that while all derivatives form one-dimensional (1D) supramolecular tapes through C–H⋯O interactions, their 3D architectures differ significantly: 3b and 3c rely on a diverse combination of π⋯π stacking and lone pair⋯π contacts, whereas 4 is governed by highly directional stacking between the pyran and pyridine rings. Hirshfeld surface analysis and CE-B3LYP energy framework calculations quantified the balance between intermolecular forces, showing that 3b is dispersion-dominated (H⋯H, 43.5%), while 3c achieves a balanced electrostatic–dispersion regime due to the nitro group, which increases O⋯H/H⋯O contacts to 37.1% and yields the highest stabilization energy (−69.1 kJ/mol). These results demonstrate that the electronic nature of the substituents at the 3- and 6-positions drastically modulates the hierarchy of non-covalent interactions, providing key insights for the crystal engineering of coumarin-based supramolecular systems. Full article

The development of high-performance adsorbents for treating dye-laden wastewater necessitates a deep understanding of structure–property relationships. This study presents a systematic investigation into the role of carbon material dimensionality (0D biochar, BC; 1D carbon nanotubes, CNT; 2D graphene oxide, GO) in modulating the properties of a dual physically crosslinked sodium alginate/polyacrylamide (SA/PAM) hydrogel for methylene blue (MB) adsorption. A series of composite hydrogels was fabricated via a sequential physical crosslinking strategy. Comprehensive characterization confirmed the successful incorporation and dispersion of carbon materials within the dual network. The three hydrogels showed good mechanical properties. Under the conditions of 25 °C, an initial MB concentration of 100 mg/L, and pH 10–11, the incorporation of carbon materials enhanced the adsorption capacity, with maximum adsorption capacities of 411.5, 410.6, and 422.8 mg/g for BC-H, GO-H, and CNT-H, respectively. Coexisting constituents in real water samples reduce adsorption capacity via competitive adsorption and interfacial interference. After five consecutive adsorption–desorption cycles, the adsorption capacities of BC-H, GO-H, and CNT-H decreased to 57.7%, 67.2%, and 61.7% of their initial values, respectively. Adsorption isotherm and kinetic studies revealed that the process followed the Langmuir model and pseudo-second-order kinetics, indicative of monolayer chemisorption. Mechanistic analysis identified synergistic contributions from electrostatic attraction, π-π stacking, and physical entrapment. Physical structural changes and chemical site occupation are the main reasons for the decrease in the adsorption performance of hydrogels during cyclic use. This work provides a rational design strategy for advanced adsorbents and a theoretical foundation for efficient dye wastewater remediation. Full article

Interactions between resveratrol and biological or carrier systems play a key role in determining its bioavailability, stability, and delivery performance. These interactions involve proteins, lipids, cyclodextrins, nucleic acids, polysaccharides, and other formulation matrices, and are governed by noncovalent forces such as hydrogen bonding, hydrophobic interactions, π–π stacking, and desolvation effects. This review examines how complementary spectroscopic, calorimetric, structural, and computational techniques are used to characterize resveratrol interactions. Fluorescence, UV–visible spectroscopy, circular dichroism, FTIR, NMR, ITC, DSC, X-ray diffraction, molecular docking, and molecular dynamics simulations are discussed according to their contribution to binding analysis, conformational assessment, thermodynamic interpretation, structural organization, and complex stability. By integrating these approaches, this review provides a technique-oriented framework for understanding resveratrol binding and guiding the development of more stable resveratrol-based carrier systems and bioactive formulations. Full article

Zeolite-based composite nanomaterials represent a versatile and mechanistically rich platform for the removal of organic micropollutants (OMPs)—including pharmaceuticals, endocrine-disrupting compounds, pesticides, and per- and polyfluoroalkyl substances (PFAS)—from contaminated water systems. Although pristine zeolite frameworks provide well-defined microporous architectures, tunable Si/Al ratios, and ion-exchange capacity, their intrinsic hydrophilicity restricts interaction diversity and limits performance toward the structurally heterogeneous OMPs prevalent in real aquatic environments. Composite integration with carbonaceous nanophases, functional polymers and surfactants, and catalytically active metal oxide nanoparticles substantially extends this interaction repertoire, yielding multifunctional materials whose adsorption performance exceeds that of the individual components. Drawing on a systematic survey of peer-reviewed literature published between 2016 and 2026, this review develops a mechanism-oriented, structure–property–performance framework examining five dominant adsorption mechanisms—electrostatic attraction, π–π stacking, hydrogen bonding, hydrophobic partitioning, and micropore confinement—in relation to composite nanoarchitecture, surface chemistry, and structural parameters. The modulating influence of realistic water matrix conditions on adsorption efficiency is critically assessed, alongside challenges of regeneration, long-term stability, metal leaching, and the persistent gap between laboratory-scale synthesis and scalable deployment. Priority research directions are identified, including standardized performance evaluation under environmentally representative conditions and rational design of hierarchical multifunctional nanocomposites from earth-abundant and waste-derived precursors. Full article

Chirality is a cornerstone of biological systems and pharmaceutical activity, driving a critical need for rapid and sensitive enantioselective analytical methods. Covalent organic frameworks (COFs) have emerged as versatile porous materials, and their chiral counterparts, chiral COFs (CCOFs), uniquely combine high surface area, pre-designable pores, and a confined chiral microenvironment, making them exceptional platforms for enantioselective fluorescence sensing. This review systematically summarizes recent advances in the construction and application of CCOFs for enantioselective fluorescence sensing. We first outline the primary synthetic strategies for CCOFs, including direct synthesis, post-synthetic modification, and chiral induction. Subsequently, based on the direction of fluorescence signal change upon analyte binding, we classify the sensing mechanisms into three categories: “turn-off” (quenching via static complexation or photoinduced electron transfer), “turn-on” (enhancement through rigidification or suppression of electron transfer), and ratiometric (self-calibrating dual-emission response). Representative examples for the detection of amino acids, amino alcohols, terpenes, and saccharides are highlighted for each mode. Special emphasis is placed on structure–property relationships, such as the synergistic roles of hydrogen bonding, π–π stacking, and framework confinement in amplifying enantioselectivity. Finally, we discuss current challenges and future perspectives, including the rational design of ratiometric sensors, integration into practical devices, and the convergence with machine learning to advance the field of smart chiral sensing. Full article

This study presents the synthesis and use of a novel bamboo-derived magnetic activated carbon (BMAC) for the effective removal of cationic and anionic dyes, specifically methylene blue (MB), methyl orange (MO), and sunset yellow (SY), from aqueous solutions. The adsorbent was synthesized using thermal carbonization and subsequent inclusion of magnetic oxide, yielding a porous structure with improved adsorption and magnetic separation properties. Thorough characterization utilizing SEM, EDX, BET, FTIR, XRD, and TGA/DTA validated the creation of a highly porous material including uniformly dispersed magnetic particles and several surface functional groups. Batch adsorption tests were performed to examine the influences of contact time, adsorbent dosage, initial dye concentration, pH, and temperature. The findings indicated rapid adsorption kinetics, with equilibrium reached in around 60–70 min, and adsorption capacity ranked as MB > MO > SY. Augmenting adsorbent dosage enhanced removal efficiency but diminished adsorption capacity per unit mass due to site unsaturation. The maximum adsorption capacities (q_m) of BMAC were 58.9, 56.3, and 32.7 mg/g for MB, MO, and SY, respectively, as determined from the Langmuir isotherm model, indicating superior performance compared with other reported magnetic activated carbon. The adsorption process was determined to be exothermic and spontaneous, as evidenced by thermodynamic characteristics. The equilibrium data were optimally characterized by the Langmuir isotherm model, indicating monolayer adsorption, whereas the kinetic studies conformed to the pseudo-second-order model, signifying that chemisorption is predominant. The adsorption mechanism encompasses electrostatic interactions, π–π stacking, hydrogen bonding, van der Waals forces, pore filling, and surface complexation with magnetic oxides. The findings indicate that BMAC is an efficient, sustainable, and magnetically recoverable adsorbent for the elimination of both cationic and anionic dyes from wastewater. Full article

Silk fibroin (SF)–polyphenol systems have emerged as a versatile class of gels and hydrogels in which supramolecular interactions and dynamic crosslinking regulate network formation, responsiveness, and multifunctional performance. Polyphenols interact with SF through hydrogen bonding, hydrophobic interactions, π–π stacking, metal coordination, and covalent crosslinking, thereby modulating conformational transitions, gelation behavior, structural stability, and interfacial functionality. These interaction mechanisms enable the development of SF–polyphenol gel systems with tunable mechanical properties, wet adhesion, antioxidant activity, self-healing capability, and stimuli responsiveness. This review summarizes recent advances in SF–polyphenol gels and hydrogels, with particular emphasis on molecular interaction mechanisms, gelation and fabrication strategies, responsive behaviors, and structure–property relationships. Representative preparation approaches, including solution blending, electrospinning, impregnation–adsorption, enzymatic crosslinking, metal–phenolic coordination, and photo-initiated processing, are systematically discussed in relation to their effects on network architecture and functional output. The responsive behaviors of these systems under pH, redox, electrical, thermal, and optical stimuli are also analyzed from the perspective of dynamic gel networks and adaptive material design. Emerging applications of SF–polyphenol gels in bioadhesives, delivery platforms, flexible bioelectronics, wound-related materials, and sustainable functional systems are highlighted. Current limitations associated with polyphenol instability, formulation sensitivity, reproducibility, and scale-up are critically discussed, together with future opportunities for predictive design of gel-based natural polymer systems. This review provides a comprehensive framework for understanding SF–polyphenol gelation and for guiding the development of next-generation multifunctional gels and hydrogels. Full article

Anthocyanin stability substantially determines the postharvest storage quality of red Huajiao (Zanthoxylum bungeanum Maxim.). Herein, the composition of red Huajiao anthocyanins (RHAs) was characterized, and the copigmentation performance of seven phenolic compounds with RHAs was comparatively evaluated, together with verifying their practical efficacy in maintaining the overall quality of red Huajiao during frozen storage. UPLC-Q-TOF-MS/MS analysis identified ten anthocyanin monomers in RHAs, among which delphinidin-3,5-diglucoside (D3,5G, 28.23%), and delphinidin-3-O-glucoside (D3G, 14.86%) were verified as the predominant monomers. Naringin (NA) exhibited an optimal copigmentation effect, achieving a maximum color enhancement rate of 19.46% at a 1:40 molar ratio and a pH of 3.0 at 20 °C, while thermodynamic tests verified the excellent stability of the naringin–RHA complex. The copigmentation interactions between RHAs and copigments were largely attributed to hydrogen bonds, π–π stacking, and alkyl hydrophobic interactions. Considering practical application cost and flavor compatibility, chlorogenic acid (CGA) was selected as the preferred alternative copigment. Frozen storage tests suggested that soaking pretreatment with 10 mmol/L CGA effectively delayed color fading and maintained the integrity of the oil gland and the good sensory quality and color attributes of red Hujiao, with no adverse impacts on its inherent flavor and numbing components. Collectively, phenolic-mediated intermolecular copigmentation represents an efficient technical means for stabilizing color and maintaining the commercial quality of postharvest red Huajiao during frozen storage. Full article