Abstract Simultaneous trace monitoring and ambient detoxification of hexavalent chromium (Cr(VI)) in complex industrial wastewater remain a critical challenge due to matrix interferences and the conventional need for auxiliary chemical reductants. Herein, an asymmetrically coordinated Ni(MBI)2 single-atom catalyst (SAC) featuring a polarized N2NiS2 electronic architecture was synthesized via a one-pot, thiol-assisted route for dual-mode ultratrace detection and ambient chemical remediation. The atomic dispersion and molecular identity of the Ni sites were established by integrating HR-ESI-MS (<3 ppm), XRD, and quantitative XPS analysis to confirm isolated Niδ+ centers. Operating across an extreme pH range (1–14), the system achieved subppb electrochemical detection limits (down to 0.290 ppb in acidic medium) and was validated in raw, alkaline leather-industry wastewater with a recovery rate of 99.58 ± 3%. Electrocatalytic testing demonstrated a maximum sensitivity of 9702.5 μA ppm–1 cm–2 and ultralow LODs of 0.530 ppb (alkaline), 0.413 ppb (neutral), and well below the WHO limit of 0.005 ppm. Concurrently, the immobilized SAC array on portable polypropylene discs enabled rapid, visual photoluminescent monitoring (92.4% quenching efficiency) with high tolerance against cocontaminants. Without external light or chemical inputs, the catalyst sustained ambient reduction of 81.2% Cr(VI) within 30 min (k ≈ 0.0505 min–1). DFT, XPS, and EIS revealed that broken coordination symmetry induces an exceptional surface dipole moment (2.82D) and hard–soft “push-pull” charge redistribution. This localized polarization promotes Cr oxyanion chemisorption (−4.25 eV) and overcomes electric double-layer transport resistance, establishing a versatile framework for self-monitoring remediation of carcinogenic chromium in water.
Abstract Despite the historical significance of ammonia synthesis, conventional models (which identify multi-atom ensembles as active sites) fail to rationalize periodic trends in catalytic activity. In this work, we propose a novel mechanistic framework governed by the valence electronic configuration of metal atoms, specifically the availability of exposed half-filled orbitals (HFOs). It is assumed that catalytic efficiency relies on single active site to simultaneously cleave H–H and N–N bonds while serving as templates to facilitate N–H bond formation, which is suggested here as the rate-determining step. The model suggests that Group 8 metals (Fe, Ru, Os), possessing four HFOs, may mediate the formation of two N–H bonds per N–H bond formation step. Conversely, Group 9 metals, with three HFOs, are proposed to be kinetically limited to forming a single N–H bond, while Groups 10–12 lack sufficient HFOs for supporting N–H bond formation. Furthermore, the inactivity of Groups 4–7 might be attributed to stable nitride formation occupying available orbitals. By correlating catalytic performance directly with intrinsic electronic configurations rather than empirical macroscopic descriptors, and by framing the catalyst as an orbital template that directs bond reorganization rather than merely a substrate for intermediate adsorption/desorption, this framework may explain the necessity of catalysts and offer a theoretical basis for a priori catalyst design tailored to specific atomic properties.
Abstract The ability to separate and detect lipid metabolites in single cells has been achieved using a miniaturized thin-layer chromatography (TLC) platform termed picoTLC (pTLC). However, continued innovations in the matrix fabrication, lipid reporter development, and single-cell workflow will broaden the applicability of pTLC to single-cell assays. In this study, we report three advances: a simple post-fabrication process [hydrothermal treatment (HT)] to modify the pTLC silica matrix, a novel clickable lipid reporter to assay metabolism of alkylglycerol (an ether lipid), and a fix-click strategy to prepare cells for the pTLC assay of a metabolized lipid reporter. HT was performed by heating pTLC chips in a silica-saturated aqueous solution with cetyltrimethylammonium bromide (CTAB) followed by slow cooling to generate a co-precipitate of silica/CTAB on the silica matrix. After extraction of CTAB, a mesoporous silica deposition was present with a 3-fold increase in surface area of the silica matrix on the HT processed pTLC chip. The separation performance on pTLC was significantly improved by HT, supporting the separation of five model fluorescent lipids with a resolution >1 for all adjacent lipids that was not achievable without HT. Given the growing importance of ether lipids such as alkylglycerol and its relatives in health and disease, a novel clickable lipid (S)-3-(hexadec-15-yn-1-yloxy)propane-1,2-diol (Reporter 1) was synthesized as a reporter for measuring alkylglycerol metabolism in addition to a companion nonmetabolizable lipid as a control (R)-4-((hexadec-15-yn-1-yloxy)methyl)-2,2-dimethyl-1,3-dioxolane (Reporter-2). A fix-click strategy was adapted to provide a simple, easy-to-use workflow for measurement of the reporter lipid metabolism in single cells by pTLC. These combined advances enabled the identification of metabolites formed from the novel lipid reporters in single leukemic cells and will further broaden the application of pTLC to report lipid metabolism at the single-cell level.
Abstract Liquid-metal droplet impact plays a key role in thermal management, coating, and additive manufacturing, yet its dynamics on rough and heated surfaces remain to be elucidated. This study experimentally investigates the impact of oxidized Galinstan droplets on solid substrates, isolating the effects of surface roughness and substrate temperature in the absence of solidification. Experiments were conducted over wide ranges of Weber number (0.15 ≤ We ≤ 720), average surface roughness (0.2 nm ≤ Ra ≤ 19.5 μm), and surface temperature (25 °C ≤ Ts ≤ 400 °C). Our results show that surface roughness promotes splashing by reducing the critical impact velocity. By fitting the experimental data within the explored parameter range, an empirical splashing threshold, ReOh4/5 = 9.8r–0.28, is established by incorporating the dimensionless roughness (r), Reynolds number (Re), and Ohnesorge number (Oh). Despite its strong influence on splashing, surface roughness has a negligible effect on the maximum spreading factor (βmax) due to Galinstan’s high surface tension. Substrate temperature likewise exerts only a minor influence, as the droplet temperature variation during spreading causes only minor changes in the liquid properties and subsequent impact dynamics under our conditions. For all Ts and Ra conditions, the experimental data of βmax collapse onto an empirical correlation, βmax = 0.1(2154 + We/Oh)0.3 for Oh∼O(10−4) and 0.15 ≤ We ≤ 720.
Abstract Glycine, alanine, and serine are three different amino acids that were used as structural building blocks to synthesize three different cholesterol-based amphiphiles (CAPs). Their gelation behavior was systematically examined in binary solvent systems using a wide range of methods, such as UV–vis spectroscopy, FT-IR spectroscopy, NMR spectroscopy, rheological measurements, SEM, and XRD. It is interesting to note that all composites showed outstanding adsorption behavior toward water-soluble dyes. The CSAP gel matrix achieved a maximum dye adsorption capacity of approximately 272 mg/g for the calcein dye in aqueous solution. The dye separation study indicates that recyclable CAP amphiphiles are effective adsorbents for large-scale environmental remediation. Additionally, the fabricated matrix demonstrates potential for separating oil from an oil–water mixture with >97% separation efficiency. Extensive in vitro studies using the anticancer drug doxorubicin hydrochloride (DOX), fluoroquinolone antibiotic norfloxacin, and a biomolecule vitamin B12 were conducted to evaluate the release profile of the organogels, aiming to assess their potential for versatile biomedical applications in drug delivery systems in acidic pH.
Abstract High-speed atomic force microscopy (HS-AFM) enables visualization of biomolecular dynamics in solution with high spatiotemporal resolution but requires substrates that support stable adsorption without perturbing their structure or dynamics. Mica is widely used as an HS-AFM substrate because it provides an atomically flat surface. Several methods have been proposed to functionalize mica surfaces, but they are not suitable for all biomolecules. Here, we expand the HS-AFM substrate toolbox by introducing methyl- and carboxyl (COOH)-functionalized mica surfaces based on a common silanization strategy. In particular, a COOH-functionalized mica substrate was prepared via a mild thiol–maleimide coupling reaction, enabling efficient surface modification under aqueous conditions. Using proteins with different charges and shapes, we evaluated adsorption and diffusion behaviors on these substrates by HS-AFM. Distinct differences in molecular mobility and binding were observed depending on surface properties. These results provide practical guidelines for substrate selection and broaden the applicability of HS-AFM to diverse biomolecular systems.
Abstract Conventional textile-based strain sensors suffer from critical limitations in moisture-rich or aquatic environments due to their inherent hydrophilicity and weak interfacial adhesion between functional coatings and fibers, which severely restrict their practical application for human motion monitoring in amphibious scenarios. Herein, we proposed a bioinspired concept reinforced superhydrophobic textile (BCRST)-based strain sensor via a combined dipping–spraying technique, which integrated a biomimetic copolymer (HE-co-SV) as an adhesive bridge between a superelastic textile substrate and a fluorinated Fe3O4/MWCNTs conductive composite coating. Therefore, the sensor exhibited a GF of 3.81 (0–120% strain) and 16.1 (120–180% strain), excellent dynamic stability under cyclic stretching, and remarkable durability over 1000 cycles (25% strain). More importantly, the BCRST sensor maintained stable superhydrophobicity even under 180% strain and after 2000 deformation cycles (stretching, bending, and twisting, respectively), enabling reliable real-time monitoring of finger and wrist movements in both air and water, which conventional textile-based strain sensors could not achieve. This bioinspired strategy offers a satisfactory paradigm for designing amphibious, durable, and high-performance wearable sensors.
Abstract Two-dimensional (2D) van der Waals materials, especially transition-metal dichalcogenide molybdenum disulfide (MoS2), have emerged as key candidate materials for advancing optoelectronics and integrated circuits due to their unique physical properties. However, the high contact barrier between the metal and semiconductor has hindered further performance improvement. Here, we introduce a novel triboelectric plasma regulation technique aimed at reducing the contact barrier between the metal and semiconductor. By injecting electrons into the S-vacancy and keeping them at the defect sites, stable electron-vacancy complexes are formed, which induce an external reverse electric field and effectively reduce the contact potential barrier between the metal and the semiconductor. At the same time, the efficiency of free-carrier injection is enhanced, significantly improving the optoelectronic performance and gate modulation capability of the device. The results show that the photoresponse performance and gate modulation ability of MoS2 devices grown by chemical vapor deposition (CVD) have been improved by 22 times and 3 orders of magnitude, respectively. This triboelectric plasma regulation technique demonstrates great potential for optimizing the performance of 2D semiconductor devices.
Abstract Polyaniline (PANI)–gold nanoparticles (AuNPs) nanocomposites have emerged as promising electroactive interfaces due to enhanced interfacial charge-transport properties. In situ polymerization is a highly effective synthesis strategy for PANI/AuNPs; however, its effectiveness is often limited by the aggregation of citrate-capped AuNPs in acidic conditions essential for aniline polymerization. Herein, we report a chitosan-mediated in situ polymerization, wherein chitosan acts as a multifunctional macromolecular stabilizer, providing electrostatic and steric hindrance that preserves the nanoscale dispersion of metallic Au nanodomains under strongly acidic polymerization conditions. Isothermal titration calorimetry (ITC) revealed thermodynamically favorable binding interactions between chitosan and Au nanodomains relative to ANI/HCl–AuNPs interactions, confirming enthalpy-driven stabilization in an acidic environment. Spectroscopic investigations (UV–Vis and ESR) demonstrated enhanced polaron generation within the PANI emeraldine salt backbone, indicating strong electronic coupling between the π-conjugated polymer chains and embedded Au nanodomains. Microscopic analysis (FESEM and TEM) confirmed a nanofibrous morphology with uniformly distributed metallic nanodomains, forming continuous charge percolation pathways. Subsequent electrochemical studies revealed improved interfacial charge-transfer kinetics marked by an increased anodic peak current in cyclic voltammetry (1030 μA) and reduced charge-transfer resistance (704 Ω) in electrochemical impedance spectroscopy. Furthermore, its applicability as an electroactive interface was validated by leveraging its natural affinity toward hyaluronic acid, enabling quantification in the linear range of 50 ng/mL to 450 ng/mL with a detection limit of 7.07 ng/mL. Thus, the resulting polaron-engineered PANI/AuNP composite with superior structural and electrochemical properties establishes a robust platform for accelerated interfacial charge transport and electroanalytical applications. Additionally, CS-mediated in situ polymerization presents a feasible choice for hybridizing PANI and citrate-capped metal nanoparticles, which has broader prospects in electroanalytical and optoelectronic applications.
Abstract Surface ligand engineering based on reversible supramolecular hydrogen bonding provides a versatile strategy for programmable nanoparticle (NP) self-assembly, yet quantitatively linking the molecular structure to interparticle interactions remains challenging. Here, explicit solvent molecular dynamics (MD) simulations are used to study Au nanoparticles functionalized with diaminopyridine (DAP) and thymine (Thy) ligands, revealing how chemical modification, steric effects, ligand flexibility, and solvent environments regulate interparticle interactions. Methylation weakens hydrogen-bond-driven attraction but is limited by restricted changes in the overall ligand-shell configuration. Introducing flexible alkyl side chains enhances steric hindrance and reduces direct contact between supramolecular binding groups, allowing interparticle interactions to vary from attraction to repulsion. In contrast, rigid phenyl side chains modulate the magnitude of the interparticle attraction by constraining ligand mobility and conformational rearrangement. The interfacial solvation environment enables nonmonotonic modulation of interparticle interactions by regulating ligand-shell solvation states and supramolecular interactions. This work reveals molecular-level mechanisms underlying the regulation of interparticle interactions through supramolecular ligand design and solvent environments, providing rational guidelines for tuning interaction properties in nanoparticle assembly systems.
Abstract Rational design of hierarchical pore architectures in biomass-derived carbon remains a critical scientific challenge for enhancing catalytic performance. This study pioneers a novel dual-etching strategy combining H3PO4 chemical pre-etching with plasma physical re-etching to construct a wheat straw charcoal catalyst (E-EWC) for optimizing peroxymonosulfate (PMS) activation efficiency to degrade organic pollutants. Morphological and pore structure analysis revealed the synergistic effect of this dual-etching process on constructing a continuous hierarchical channel structure interconnecting micro- and mesopores of E-EWC, which facilitates PMS activation and accelerates electron transfer. Meanwhile, quantitative structure–activity correlation analysis indicated that mesopore volume more favorably promotes nimesulide (NIM) degradation (R2 = 0.8511). Consequently, E-EWC achieved a satisfactory 97% removal rate of NIM within 60 min primarily by non-free-radical pathways and electron transfer, whose degradation kinetic constant was approximately 3- and 4-fold higher than those of single-etched EWC and E-WC catalysts, respectively. Furthermore, E-EWC’s superior chemical stability, strong anti-interference ability, and low toxicity of NIM degradation intermediates collectively demonstrate it as an effective PMS activator for water treatment applications. This work not only elucidates the critical role of hierarchical porosity in non-radical PMS activation but also provides an efficient strategy for designing advanced carbon catalysts for water remediation.
Abstract Electric fields reorganize interfacial water and can therefore alter clathrate hydrate growth, but the molecular origin of the frequently nonmonotonic response remains unresolved. Here, molecular dynamics simulations are used to examine seeded hydrogen-tetrahydrofuran (H2-THF) structure-II hydrate growth in a gas–liquid-hydrate system at 270 K and 40 MPa under fields of 0–0.6 V/nm. Among the sampled conditions, 0.4 V/nm produces the largest cage-growth rate and H2 incorporation, whereas fields of 0–0.2 V/nm have modest effects and 0.3 V/nm shows pronounced trajectory dependence. Stronger fields initially accelerate cage formation but subsequently promote stagnation or cage loss. The nonmonotonic response arises from a coupled multiscale mechanism linking field-induced dipole ordering, interfacial hydrogen-bond dynamics, and cage-topology evolution. Specifically, moderate fields (0.4 V/nm) induce weak dipole preorganization that extends the interfacial hydrogen-bond lifetime by approximately 18%, which in turn minimizes anomalous cage transformations while maximizing transformation pathway diversity, thereby coupling molecular orientation through hydrogen-bond persistence to efficient and sustained cage-network propagation. In contrast, strong fields (≥0.5 V/nm) impose coercive dipole alignment that suppresses hydrogen-bond exchange, contracts the cage-transformation network to a restricted set of reversibly interconverting cage pairs, and destabilizes long-range lattice propagation. These results show that maximum clathrate growth does not coincide with maximum molecular alignment. Instead, an intermediate field creates an adaptable interfacial hydrogen-bond network that couples water orientation, cage topology, and guest incorporation.
Abstract Solar-driven photocatalytic H2O2 production provides a sustainable alternative to the energy-intensive anthraquinone process. However, graphitic carbon nitride (CN) suffers from rapid charge recombination and inefficient activation of molecular oxygen, leading to limited H2O2 production. Herein, we report a Schiff-base-interface-engineered organic-polymer-functionalized CN (ACD-DAMP-CN), synthesized via hydrothermal condensation of oxidized β-cyclodextrin (ACD), 4,6-diamino-2-mercaptopyrimidine (DAMP), and surface amino groups on CN. The covalently coupled Schiff-base interface regulates the electronic structure of CN, promotes directional interfacial charge transfer, and facilitates the selective two-electron oxygen reduction reaction (2e– ORR) toward H2O2 generation. Consequently, ACD-DAMP-CN achieves an H2O2 evolution rate of 600 μmol g–1 h–1 under simulated sunlight irradiation in pure water without oxygen aeration, which is 18.75 times higher than that of pristine CN. Experimental characterizations combined with DFT calculations reveal that electron redistribution across the Schiff-base bridge enhances charge separation by transferring electron density from the electron-rich DAMP moieties to the CN framework, thereby promoting efficient 2e– ORR. Moreover, the catalyst exhibits excellent stability over five consecutive cycles and maintains high activity over a wide pH range (2–12). The in situ-generated H2O2 further enables efficient photo-Fenton degradation of ciprofloxacin, demonstrating a feasible strategy for integrating selective photocatalytic H2O2 production with solar-driven environmental remediation.
Abstract Ferrofluid pumps, by controlling the morphology and spatial distribution of ferrofluids through an external magnetic field, achieve noncontact driving and the conversion of magnetic energy into fluid mechanical energy, showing potential application in microfluidic systems. However, the synergistic influence mechanism of interfacial friction within the confined space, pump cavity size effect, and ferrofluid filling volume on pumping behavior remains unclear. To address these issues, a variable-parameter magnetically driven ferrofluid pump experimental platform was constructed to investigate the effects of interfacial wettability, pump cavity geometry, and initial filling angle on pumping behavior. Experimental results show that the initial filling angle affects pumping performance by changing the effective magnetic drive volume. In the low-speed range (1–30 rpm), the flow rate difference is small under different filling angles. Under a back pressure of 10 cm H2O, a 40° filling angle increases the starting speed to approximately 10 rpm. In the medium-speed range (40–80 rpm), the flow rate follows the pattern of 50°>45°>40°, and the system has an optimal filling range (45°–50°). Interfacial wettability modulates frictional behavior by altering the spatial structure of ferrofluids. A continuous liquid film structure forms on the PMMA surface, achieving a flow rate of approximately 3500 μL/min at 30 rpm. On the glass surface, a discrete droplet structure forms, reducing the flow rate to approximately 1900 μL/min (about 54% of that of PMMA). The PC surface exhibits a liquid film-droplet mixing state, achieving a trade-off between pumping efficiency and structural stability. Geometric scale affects pumping performance by altering the magnetic driving torque and interfacial constraint strength. A 14 mm pump cavity fails to establish an effective pressure differential, a 24 mm pump cavity increases the flow rate by approximately 20%–40% at low speeds but fails at approximately 700 rpm, while a 19 mm pump cavity can maintain flow at approximately 800 rpm. This study reveals the coupling mechanism between interfacial structural stability, effective magnetic driving volume, and resistance dissipation, providing a control design strategy for microscale thermal management, biomicrofluidics, and other confined space magnetically driven transport systems.
Abstract Soil erosion remains a pressing global environmental challenge, and polyelectrolyte complexes (PECs) have emerged as promising stabilizing agents for soil erosion control. However, the mechanistic basis of their performance, particularly the complex interplay between the structure of PECs, rheological behavior, and the associated flow field within the surrounding environment, remains poorly understood. In this study, we constructed PECs by combining a short-chain polyanion and a long-chain polycation to form a polymeric network, using polyphosphoric acid (PPA) and poly(diallyldimethylammonium chloride) (PDDA) as the model components. Electrophoretic mobility (EPM) measurements, hydrodynamic diameter analysis by dynamic light scattering (DLS), and quartz crystal microbalance with dissipation (QCM-D) collectively reveal an electrostatically driven self-assembly process in which long-chain PDDA provides the scaffold while short-chain PPA acts as a molecular connector. Rheological measurements show that the shear resistance of the PDDA/PPA network, characterized by the effective shear rate γ̇ and the characteristic shear stress τ at the G′ maximum, can be tuned by adjusting the PPA dosage. Macroscale hydrodynamic shear tests further demonstrate a strong positive correlation between consolidated-sand stability and the rheology-derived network strength, with both γ̇ and τ at the G′ maximum reaching a maximum at a PDDA:PPA monomer molar ratio of 1:5. Scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX) directly visualizes interparticle physical bridging that promotes sand aggregation. Collectively, these results suggest that the PPA-regulated strength of the PECs network is an important factor influencing sand-stabilization performance. Such findings shift the design philosophy of sand stabilizers from conventional surface adhesion toward the internal structural engineering of particle-bridging networks.
Abstract The discharge of saline wastewater with high-concentration organic pollutants from industries such as intensive seawater aquaculture poses a severe threat to aquatic ecosystems, calling for green and energy-efficient treatment technologies. Here, this study reports a rationally designed photothermal-photocatalytic multifunctional hydrogel-coated sponge (TiO2@PAM@PPy@PDA@MS, TPpPM) for simultaneous solar-driven water evaporation and in situ degradation of organic contaminants in saline wastewater. The composite is fabricated by sequentially coating polyacrylamide (PDA) and polypyrrole (PPy) onto a three-dimensional melamine sponge (MS) skeleton, followed by in situ polymerization of a polyacrylamide (PAM) hydrogel network loaded with TiO2 nanoparticles. The optimized TPpPM exhibits nearly 100% solar absorption across the full spectrum (250–2500 nm), achieves a surface temperature rise of 15 °C under one sun irradiation during solar-driven water evaporation, and delivers an evaporation rate of 1.16 kg m–2 h–1. The integrated PAM hydrogel provides superhydrophilicity and abundant anchoring sites for the low-cost but effective photocatalyst TiO2, enabling efficient photocatalytic degradation of 90% organic contaminants within 80 min. More importantly, a gravity-driven continuous-flow device incorporating TPpPM demonstrates excellent antiscaling performance and achieves a clean water yield of 400 mL m–2 h–1 with a salinity of 0.015% while simultaneously reducing total organic carbon (TOC) by 12.8% and total nitrogen (TN) by 38.2% from real shrimp aquaculture effluent. COMSOL Multiphysics simulations validate the coupled transport processes of interfacial evaporation transmembrane vapor diffusion and latent heat recovery. This work provides a low-cost and sole solar-driven strategy for treating complex saline wastewater, with promising potential for large-scale deployment under carbon-neutral scenarios.
Fluazinam is a benzamide fungicide commonly used in agricultural production to prevent and control fungal-induced plant diseases. However, its residues in food products can pose potential health hazards. To address this issue, we have developed an electrochemical sensor based on a MOF-5/AB-modified glassy carbon electrode (GCE) for sensitive detection of fluazinam. In this work, a high-performance electrochemical sensor was fabricated via a simple composite strategy by combining AB, which possesses high electrical conductivity and superior electron transfer ability, with MOF-5, a material featuring a well-developed porous structure and large specific surface area. The structural and morphological characteristics of the MOF-5/AB and electrochemical sensing performance toward fluazinam of MOF-5/AB/GCE are investigated. The MOF-5/AB/GCE exhibited outstanding electrochemical sensing performance for fluazinam detection, providing an ultralow detection limit of 0.0166 μM, a wide linear range of 0-100 μM, high sensitivity, excellent reproducibility and stability, and remarkable selectivity against common interfering species. In real samples, fluazinam yielded high recovery rates, confirming the potential of MOF-5/AB/GCE for practical environmental and biomedical monitoring applications. This research provides a novel and efficient sensing platform for electrochemical detection of fluazinam residues and offers a valuable reference for modification of MOFs and their extended applications in the field of electrochemical sensing.
Chemodynamic therapy (CDT), which employs •OH generated by Fenton-type reactions to trigger cancer cell death, has received much attention in recent years. However, CDT efficacy is restricted by insufficient H2O2 levels and reactive oxygen species (ROS) consumption by antioxidants in tumor cells. Amplification of intracellular oxidative stress is an effective strategy for enhancing CDT efficiency. In this study, chitosan (CS)-protected iron peroxide nanoclusters (CS@FeNCs) were prepared via the reaction of Fe2+ and H2O2 in CS medium, and the resulting product can release H2O2 and convert H2O2 to •OH through the Fenton reaction under acidic conditions. To suppress the consumption of ROS by glutathione (GSH), gold nanoclusters templated by histidine (His) (His@AuNCs) were used to scavenge intracellular GSH by forming GSH@AuNCs. Furthermore, a nanocomposite was fabricated by encapsulating CS@FeNCs and His@AuNCs with polyvinylpyrrolidone (PVP), and the resulting PVP@Fe-Au can effectively amplify the level of oxidative stress in tumor cells by providing H2O2 and depleting GSH, which induced cancer cell apoptosis and death. It is hoped that the developed PVP@Fe-Au can provide an efficient strategy for designing high-efficiency CDT agents via boosting ROS generation and suppressing the antioxidation system.
The physicochemical properties of some lyotropic mixtures, composed of surfactant, electrolyte, decanol, and water, were studied using different Hofmeister series anions and cations of electrolytes. The effects of ions present in the intermicellar region were analyzed by comparing them with those at the micelle surfaces. Three experimental techniques were employed to investigate the lyotropic nematic phase properties. The textures of the lyotropic uniaxial (discotic nematic─ND and calamitic nematic─NC) and biaxial nematic (NB) phases were characterized by polarizing optical microscopy. The transitions from the uniaxial to the biaxial nematic phases (ND to NB and NB to NC) were determined from the temperature dependences of the birefringences of the nematic phases via laser conoscopy. The ND to NB (32.75 to 38.45 °C) and NB to NC (28.00 to 34.55 °C) phase transition temperatures shifted towards higher temperatures by an increase in chaotropicity of cations. An opposite behavior was observed for anions, where the transition temperatures shifted towards smaller values (33.65 to 30.05 °C and 28.20 to 24.75 °C, respectively). While the former case was attributed to the weakening of the attractive interactions between kosmotropic surfactant head groups and oppositely charged electrolyte ions (cations) due to the formation of loosely bound ion pairs, the latter one was explained by the different influence of anions on free K+ ions. Some structural parameters, such as the micelle's core average dimensions, micelle shape anisotropy, and average area per surfactant head group at the micelle surface, were obtained from the analysis of small-angle X-ray scattering data. According to the data, the ions, which remain in the intermicellar region (or the Gouy-Chapman layer), similar to the effect of the ions located at the micelle surfaces in the Stern layer, affect micellization structural parameters. The results show that the interactions between ionic species, arising from their kosmotropic and chaotropic characters, in the Gouy-Chapman layer and/or in the intermicellar region play a crucial role in the formation of the lyotropic nematic phases, especially the biaxial one.
Understanding the micromechanics of debonding ice on microstructured surfaces is essential to the rational design of icephobic materials. However, the competition between interfacial debonding and cohesive fracture, along with microscale stress evolution under complex loading fields, remains unclear. This study develops a coupled computational framework that integrates a cohesive zone model with the extended finite element method to systematically investigate the loading-induced failure process of ice-solid interfaces. This framework accurately captures the mechanical competition and evolution between interfacial crack propagation and internal fracture within ice under complex structural constraints. We further elucidate stress evolution during debonding and demonstrate that rotational debonding effectively alleviates stress concentrations at the micropillar root through the coupled release of normal and tangential displacements. This provides a fundamental mechanical explanation for the weakening of the mechanical interlocking effect. Furthermore, by extracting nonlinear force-displacement responses for different failure modes, we characterize the mode-dependent mechanical response of microscale debonding. These results provide micromechanical insights into macroscopic ice adhesion and offer quantitative guidance for the morphological design of low-adhesion surfaces.
