Sediment-water interface reoxygenation by NO3-LDH promotes tetracycline degradation in sediments and modulates antibiotic resistance gene dynamics.

Engineering Mn-confined Fe0-carbon with isolated oxygen-containing groups breaks the bottleneck for concurrent self-driven Fenton degradation of antibiotics and heavy metals immobilization.

Hydroxyl radical from iridium(III)-based photosensitizer triggers PANoptosis and ferroptosis for hypoxia-tolerant photodynamic immunotherapy.

ERYTHROTOXICITY OF IRON-DOPED CERIUM OXIDE NANOPARTICLES IS MEDIATED BY ERYPTOSIS.

Recalcitrant copper-organophosphonate complexes in industrial wastewater challenge conventional advanced oxidation because their high stability and rigid coordination geometry limit radical access and utilization. Here we report a surfactant-enhanced Fenton process in which cetyltrimethylammonium bromide (CTAB) self-assembles into cationic micelles that act as supramolecular microreactors to capture and decomplex Cu(II)-hydroxyethylidenediphosphonate (Cu-HEDP). By confining the reaction in micelles, Cu(II)-HEDP was colocalized with the iron catalyst and short-lived •OH, achieving substantial decomplexation (>97%) and nearly complete removal of total phosphorus upon alkalization, markedly outperforming the CTAB-free Fenton process, which only exhibited partial decomplexation and removal of total phosphorus (≈40%) under otherwise identical conditions. Mechanistically, CTAB enriches anionic Cu-HEDP at the micellar interface and reshapes the electron distribution within HEDP, creating electron-deficient sites for •OH attack while promoting intramolecular electron transfer. Meanwhile, the positively charged micellar interface promotes Fe(III)/Fe(II) recycling and helps maintain a high •OH generation. CTAB further acts as a cationic coagulant during precipitation, neutralizing and bridging Fe(OH)3/Cu(OH)2 colloids and phosphorus-containing byproducts into settleable flocs. The process also works well for Cu(II) complexes with several other organophosphonates, suggesting a broadly applicable, interface-enabled "capture-and-degrade" approach for charged metal-organic pollutants that conventional AOPs often struggle to remove.

Copper-doped carbon dots nanozymes with dual peroxidase/catalase activities for synergistic ROS-mediated ultra-potent MRSA eradication and wound healing.

Self-Fenton processes show potential for treating acidic mine drainage (AMD), yet their efficacy is limited by inefficient conversion of in situ generated hydrogen peroxide (H2O2) to hydroxyl radicals (·OH), crucial for oxidizing highly mobile trivalent arsenic (As(III)). Here, we engineered Lewis acid sites on iron vanadate (FeVO4) and leveraged piezocatalysis to dynamically boost both the sustained generation and subsequent activation of H2O2 into ·OH under acidic conditions. Under ultrasonic excitation, FeVO4 achieved a remarkable ·OH generation rate of 334.26 μmol g-1 h-1 at pH 3.0. This system oxidized 80.14% of As(III) and concurrently adsorbed 19.14% of the resulting pentavalent arsenic (As(V)), leading to a total arsenic removal of 15.34% within 3 h. Intriguingly, the presence of As(III) accelerated ·OH production by 3-4 fold, attributed to the facilitated redox cycling of Fe sites at the FeVO4 surface. Mechanism studies confirm that Lewis acid sites are pivotal for adsorbing and activating O2 and H2O2, while piezoelectric polarization optimizes their electronic state to promote efficient ·OH formation and its diffusion into bulk solution for As(III) oxidation. This work demonstrates a novel, external-oxidant-free strategy for long-term ·OH yield via in situ piezoelectric regulation of Lewis acidity, offering a sustainable avenue for the remediation of AMD.

Effective healing of diabetic wounds remains a major clinical challenge due to persistent hyperglycemia, bacterial infections, and hypoxia. In this study, a multifunctional self-healing hydrogel by embedding Fe3O4 nanoparticles (NPs) immobilized with glucose oxidase (Fe3O4/GOD) into a dynamic Schiff base-crosslinked hydrogel matrix of composed of oxidized bacterial nanocellulose (OBNC-D), carboxymethyl chitosan (CMC), and ε-poly-L-lysine (ε-PL) is developed. The resulting Fe3O4/GOD@H hydrogel exhibited excellent injectability, mechanical robustness, and self-healing capability, attributed to dynamic imine bond formation. Functionally, the embedded Fe3O4/GOD nanozyme enabled glucose-responsive cascade reactions, generating hydroxyl radicals (·OH) under mildly acidic conditions for potent antibacterial activity, and producing oxygen under neutral conditions to alleviate local hypoxia. In vitro experiments confirmed efficient ·OH generation, sustained oxygen release, and significant antibacterial efficacy against Staphylococcus aureus and Escherichia coli. The hydrogel also exhibited good hemocompatibility and cytocompatibility, particularly at optimized nanozyme concentrations. In a diabetic rat model, Fe3O4/GOD@H markedly accelerated wound closure and achieved complete re-epithelialization within 14 days, with minimal tissue toxicity. This intelligently responsive hydrogel provides a promising strategy for diabetic wound treatment by integrating glucose regulation, antibacterial action, and oxygen delivery to overcome multiple healing barriers.

Surface-OH homolysis on Sn(OH)4: Visible-light generation of OH for solar mineralization of phenolic contaminants

Gallic acid-mediated semiquinone radicals drive a self-sustaining fenton-like system for PAH remediation in contaminated soil.

Activity-tunable bimetallic iron-cobalt nanoflowers integrated with smartphones for rapid detection of human uric acid.

Observational and modelled insights of volatile organic compounds into seasonal atmospheric oxidation capacity and radical chemistry over North China.

To investigate the role of hydrogel composition and nanozymes incorporation on the inflammatory response of encapsulated murine microglia. Sodium alginate (SA) hydrogels containing i) hyaluronic acid (HA) of low-100 kDa or high-1 MDa molecular weight and ii) Mn3O4 nanoparticles (Mn3O4-NPs) were prepared and characterized. The inflammatory response of encapsulated microglia was assessed. HA enhanced cell-biomaterial interactions and reduced cell aggregation. Under normal culture conditions, HA induced a pro-inflammatory response, particularly with high-MW HA, with a 7-fold increase in IL-6 expression and a 2.2-fold increase in TNF-α secretion. Under prolonged LPS stimulation, HA promoted an anti-inflammatory shift, with a 2-fold decrease in IL-1β expression and restored IL-4 expression to basal levels. Mn3O4‑NP-loaded hydrogels showed strong H2O2 scavenging capability, protecting cells from oxidative stress. This effect may be partially counterbalanced by •OH generation at high Mn3O4‑NP concentrations. Under short-term LPS stimulation, Mn3O4 promoted a slight pro-inflammatory response, with a 1.3-fold and 1.2-fold increase in IL-1β and TNF-α expression. However, prolonged LPS exposure reflected an anti-inflammatory scenario, with increased IL-4 and a 2.4-fold increase in Arg-1 expression. SA hydrogels are promising carriers for antioxidant nanozymes and microglia, modulating cell response under prolonged inflammation while protecting cells from oxidative stress.

Linkage-chemistry-regulated activation of ferrocene-functionalized poly(l-lysine) nanoplatforms for synergistic chemotherapy and Chemodynamic therapy.

Efficient removal of structurally diverse and persistent pharmaceutical contaminants from wastewater, particularly in mixed-pollutant systems, remains a critical challenge in advanced water treatment technologies. Conventional Fe-based photofenton systems suffer from iron (Fe) sludge generation and secondary metal contamination, limiting their practical and sustainable application. Herein, we report Fe-free photofenton catalysis enabled by interfacial V5+/V4+ redox kinetics in α- V2O5-decorated activated carbon nanotube (α-V2O5-ACNT) nanohybrids for simultaneous removal of two emerging pharmaceutical pollutants, diclofenac (DFN) and carbamazepine (CBZ), from their mixed system. Electronic coupling at the V2O5/ACNT interface promotes rapid charge separation, abundant oxygen vacancies, and dynamic V5+/V4+ redox cycling, which efficiently activates H2O2 to generate highly reactive •OH radicals without the need for Fe species. Under optimized conditions, the catalyst achieved ∼96% removal efficiency for DFN and ∼95% against CBZ within 60 min. Transient photocurrent, EPR/ESR, and radical trapping analyses confirm improved charge transport and intensified •OH generation. Density functional theory calculations further reveal favorable adsorption geometries, charge redistribution, and reactive site localization of both pollutants on defect-rich surfaces, rationalizing the observed removal pathways. This study establishes mechanistic synergy between V2O5 and ACNTs as an effective strategy for designing sustainable, Fe-free photofenton systems.

The hydroxyl radical (•OH) plays a pivotal role in atmospheric chemistry, yet the generation mechanisms of •OH at solid-water-air interfaces (SWAIs) under real atmospheric conditions remain incompletely understood and require further in-depth investigation. This study identifies mineral dust (e.g., hematite) microdroplets as an important •OH source via SWAIs photochemical reactions. Remarkably, under simulated sunlight and at pH 3, hematite microdroplets enhance •OH production by 2 orders of magnitude compared to the bulk solution. This enhanced activity is governed by their exposed facets, which regulate the iron redox cycle. SWAIs improve O2 exchange efficiency, and smaller microdroplets accelerate •OH generation owing to improved O2 accessibility. DFT results further suggest that interfacial electric fields can reduce the band gap, enhance photoinduced electron excitation, and thereby may facilitate •OH generation. Our results further demonstrate that the enhanced transformation of phenol and SO2 underscores the atmospheric significance of SWAIs. Our findings demonstrate that mineral-dust-bearing microdroplets constitute a previously overlooked yet critical source of •OH. This elucidates the crucial mediating role of SWAIs in climate-chemistry feedback loops, influencing the formation and transformation processes of sulfate aerosols, secondary organic aerosols, and greenhouse gas emissions.

Conventional antibody- or peptide-drug conjugates (ADCs/PDCs) improve tumor selectivity, yet the unimolecular integration of imaging guidance and multimodal therapy remains limited. Here, we introduce a peptide-photosensitizer-drug conjugate (P2DC) strategy that enables unified NIR-II imaging and synergistic multimodal therapy. As a proof of concept, a hypoxia-activated prodrug, IT-azo-RGD, is constructed by integrating a computationally optimized photosensitizer core, a hypoxia-cleavable azo linker bridging a drug payload, and bis-cRGDfK for multivalent integrin targeting. Theoretical calculations reveal that the active photosensitizer core (IT-m-NH2) exhibits bright NIR-II fluorescence, efficient photothermal conversion, and type-I photodynamic reactivity, while also elucidating the mechanisms underlying IT-azo-RGD self-assembles into nanospheres that undergo hypoxia-triggered disassembly upon drug release. IT-azo-RGD displays triple tumor targeting through integrin affinity, EPR-mediated accumulation, and hypoxia activation. Upon azo cleavage, •OH generation increases by approximately 6-fold, and the photothermal efficiency reaches 59.7%. These features support NIR-II imaging-guided chemo-photothermal-photodynamic synergy. In the orthotopic osteosarcoma mouse model, IT-azo-RGD achieves 97.7% tumor inhibition, suppresses lung metastasis, and shows no systemic toxicity. This P2DC concept provides a generalizable design framework for a unimolecular theranostic prodrug.

Multifunctional oxygen vacancy defect-rich magnetic nanoplatforms for MR imaging and enhanced chemodynamic therapy synergized with chemotherapy and photothermal therapy.

Despite the promise of hydrogen peroxide (H2O2)-mediated cancer therapy, its efficacy is often constrained by the insufficient endogenous H2O2 levels and immunosuppressive tumor microenvironment (TME). To address this, we designed a bimetallic peroxide nanosystem (CuZnONPs) that executes a triple-combination therapeutic strategy. In the weakly acidic TME, CuZnONPs self-supply H2O2, exert enzyme-mimetic activities to catalyze H2O2 into toxic reactive oxygen species (·OH and ·O2 -) and O2, and release Zn2+ to activate pyroptosis. Density functional theory calculations reveal that the single Cu atoms in CuZnONPs play a critical role by not only conferring peroxidase-like activity for ·OH generation but also modulating the electronic structure of adjacent Zn sites to drive cascade catalase- and oxidase-like activities for ·O2 - production. The resulting reactive oxygen species burst downregulates the GSH/GPX4 axis, disrupts redox homeostasis, and inflicts extensive damage to lipids, mitochondria, and DNA. Furthermore, Zn2+-activated pyroptosis elicits damage-associated molecular pattern release to promote dendritic cells maturation and remodel the inflammatory tumor microenvironment, ultimately converting cold tumors into hot tumors. This work establishes a TME-responsive nanoplatform that synergistically integrates catalytic therapy with pyroptosis-enhanced immunotherapy, offering new insights into the design of nanomedicines for cancer therapy.

ABSTRACT Ultrasound (US)‐triggered reactive oxygen species (ROS) generation by nano‐sonocatalysts is vital for sonocatalytic therapy. However, the therapeutic effect is hindered by the low ROS generation yield owing to sluggish charge transfer and elusive active sites. Herein, in situ oxygen vacancies (Vo)‐engineered Pd‐TiO 2 sonocatalysts with spatially separated dual reactive sites are developed, which optimize charge kinetics and amplify ROS generation. Mechanism studies revealed that US‐induced Vo serves as an electron pump, activating the Pd–O–Ti transport channel, lowering interfacial barriers and steering electron migration from TiO 2 to Pd. This ordered charge redistribution tunes the d ‐band center of Pd, designating electron‐rich Pd sites as the primary active center for O 2 adsorption and activation to produce singlet oxygen ( 1 O 2 ). Concurrently, Vo‐mediated reconstruction of Ti 3d states strengthens orbital coupling with H 2 O at the Pd–O–Ti interface, dominating the activation of H 2 O to promote the generation of hydroxyl radical (•OH). This dual‐site configuration effectively lowers the activation energy barriers, which increases the rate constants of 1 O 2 and •OH generation by 5.0‐fold and 2.7‐fold, respectively, and ultimately achieving an 87.5% tumor inhibition efficiency. This work provides molecular insights into the charge transfer cascade and critical active centers in US‐activated Pd‐TiO 2 , offering a rational paradigm for designing high‐performance sonocatalysts.