Efficient Reactive Oxygen Species Research Articles

Semiconducting Titanate Supported Ruthenium Clusterzymes for Ultrasound-Amplified Biocatalytic Tumor Nanotherapies.

The external-stimulation-induced reactive-oxygen-species (ROS) generation has attracted increasing attention in therapeutics for malignant tumors. However, engineering a nanoplatform that integrates with efficient biocatalytic ROS generation, ultrasound-amplified ROS production, and simultaneous relief of tumor hypoxia is still a great challenge. Here,wecreate new semiconducting titanate-supported Ru clusterzymes (RuNC/BTO) for ultrasound-amplified biocatalytic tumor nanotherapies. The morphology and chemical/electronic structure analysis prove that the biocatalyst consists of Ru nanoclusters that are tightly stabilized by Ru-O coordination on BaTiO3 . The peroxidase (POD)- and halogenperoxidase-like biocatalysis reveals that the RuNC/BTO can produce abundant •O2 - radicals. Notably, the RuNC/BTO exhibits the highest turnover number (63.29 × 10-3 s-1 ) among the state-of-the-art POD-mimics. Moreover, the catalase-like activity of the RuNC/BTO facilitates the decomposition of H2 O2 to produce O2 for relieving the hypoxia of the tumor and amplifying the ROS level via ultrasound irradiation. Finally, the systematic cellular and animal experiments have validated that the multi-modal strategy presents superior tumor cell-killing effects and suppression abilities.We believe that this work will offer an effective clusterzyme that can adapt to the tumor microenvironment-specific catalytic therapy and also provide a new pathway for engineering high-performance ROS production materials across broad therapeutics and biomedical fields.

Recent advances in Fenton and Fenton-like reaction mediated nanoparticle in cancer therapy

Fenton and Fenton like reaction have been well clarified as efficient reactive oxygen species (ROS) sources in tumor, and have been widely developed into a cancer treatment method. Meanwhile, transition metal-based nanomaterials with Fenton or Fenton like reaction characteristics also have been well explored as therapeutic agents for the cancer therapy, mainly in chemo-dynamic and ferroptosis induced cancer therapy. Herein,to summarize recent advances in Fenton and Fenton like reaction mediated nanoparticles for cancer therapy, in this minireview, we first introduced the mechanisms of Fenton and Fenton like reaction and two therapeutic methods based on Fenton and Fenton like reaction, and then we introduced the well-designed nanoparticles with Fenton reaction or Fenton-like reaction characteristics for the cancer therapies. Finally its challenges and perspectives are discussed.

Phototheranostic Agents Based on Nonionic Heptamethine Cyanine for Realizing Synergistic Cancer Phototherapy.

Asymmetrical heptamethine cyanine with near-infrared (NIR) absorption is used for photothermal therapy (PTT) of cancer. Aiming to overcome the drawbacks caused by the high temperature of PTT, the development of asymmetrical heptamethine cyanine with photothermal and photodynamic properties is still an attractive strategy. Different from the traditional method of the heavy atom effect, in this work, the carboxyl or sulfonic groups are introduced into the indole ring or branch chain of asymmetrical heptamethine cyanine to afford a series of new phototherapy agents. After being encapsulated by DSPE-PEG2000 , BSS-Et NPs exhibit robust photostability, efficient reactive oxygen species generation (49%), and excellent photothermal conversion efficiency of about 37.6% under 808nm laser irradiation. BSS-Et NPs possess passive tumor-targeting properties in vivo to not only visualize the tumor by NIR fluorescence imaging but also eliminate the tumor without any recurrence byphotodynamic therapy and PTT synergistic therapy under laser irradiation. In addition, benefitting from the characteristics of organic small molecules, they can be metabolized quickly through the liver without inducing toxicity in the whole body. In general, this study provides a new direction for the development of multifunctional phototherapy agents for cancer treatment.

Photochemically-driven highly efficient intracellular delivery and light/hypoxia programmable triggered cancer photo-chemotherapy

BackgroundUsing nanotechnology to improve the efficiency of tumor treatment represents a major research interest in recent years. However, there are paradoxes and obstacles in using a single nanoparticle to fulfill all the requirements of complex tumor treatment.ResultsIn this paper, a programmed-triggered nanoplatform (APP NPs), which is sequentially responsive to light and hypoxia, is rationally integrated for photoacoustic (PA) imaging-guided synergistic cancer photo-chemotherapy. The nanoplatform is constructed by in situ hybridization of dopamine monomer in the skeleton of PCN-224 and loading prodrug banoxantrone (AQ4N). Upon first-stage irradiation with a 660 nm laser, cellular internalization was effectively promoted by a photosensitizer-mediated photochemical effect. Furthermore, under second-stage irradiation, APP NPs exhibit a notably high photothermal conversion efficiency and sufficient reactive oxygen species (ROS) production for photothermal therapy (PTT) and photodynamic therapy (PDT), respectively, which not only triggers rapid intercellular drug release but also consequently aggravates tumor hypoxia levels, and aggravated hypoxia can further active the cytotoxicity of AQ4N for chemotherapy. Both in vitro and in vivo studies confirm that the dual-stage light guided photo-chemotherapy strategy exhibits a greatly enhanced anticancer effects and superior therapeutic safety.ConclusionThis work represents a versatile strategy to construct a dual-stage light induced PDT/PTT and hypoxia-activated chemotherapy nanoplatform and will be promising for the development of multistimuli-responsive nanosystems with programmable functions for precise cancer therapy.

Near-infrared light responsive intensified multiphoton ultraviolet upconversion in nanostructures towards efficient reactive oxygen species generation.

Near-infrared-to-ultraviolet (NIR-to-UV) multiphoton upconversion has recently received increasing attention owing to its promising frontier applications in the fields of biomedicine and nanophotonics. However, the realization of high-efficiency NIR-to-UV upconversion remains a dispiriting challenge due to weak excitation light harvesting and photo-conversion efficiency. Herein, we propose a mechanistic strategy to achieve intensified UV upconversion by manipulating the injected excitation energy flux. A simple LiYbF4:Tm@LiYF4 host-sensitized sublattice core-shell nanostructure was initially proposed to compete with the concentration quenching effect and increase energy transfer efficiency. Then, the organic dye ICG was further coated to introduce the antenna sensitization effect to highly increase the absorption ability of nanocrystals. After optimizing the ICG number loaded on the surface and separation distance, up to 167-fold UV upconversion emission enhancement was achieved under low-power excitation of 808 nm. More importantly, the efficient UV upconversion exhibits enhanced reactive oxygen species (ROS) generation activity by fabricating a TiO2-modified upconversion nanocomposite, revealing great application potential in frontier fields such as in vivo photodynamic therapy and bioimaging-guided therapeutics. Our results can provide versatile designs to achieve efficient UV upconversion, overcome conventional limitations, and offer exciting opportunities for potential applications in biomedical fields.

Protein-protein interactions in plant antioxidant defense.

The regulation of reactive oxygen species (ROS) levels in plants is ensured by mechanisms preventing their over accumulation, and by diverse antioxidants, including enzymes and nonenzymatic compounds. These are affected by redox conditions, posttranslational modifications, transcriptional and posttranscriptional modifications, Ca2+, nitric oxide (NO) and mitogen-activated protein kinase signaling pathways. Recent knowledge about protein-protein interactions (PPIs) of antioxidant enzymes advanced during last decade. The best-known examples are interactions mediated by redox buffering proteins such as thioredoxins and glutaredoxins. This review summarizes interactions of major antioxidant enzymes with regulatory and signaling proteins and their diverse functions. Such interactions are important for stability, degradation and activation of interacting partners. Moreover, PPIs of antioxidant enzymes may connect diverse metabolic processes with ROS scavenging. Proteins like receptor for activated C kinase 1 may ensure coordination of antioxidant enzymes to ensure efficient ROS regulation. Nevertheless, PPIs in antioxidant defense are understudied, and intensive research is required to define their role in complex regulation of ROS scavenging.

Efficient differentiation of human neutrophils with recapitulation of emergency granulopoiesis in human G-CSF knockin humanized mice.

Neutrophils are critical mediators during the early stages of innate inflammation in response to bacterial or fungal infections. A human hematopoietic system reconstituted in humanized mice aids in the study of human hematology and immunology. However, the poor development of human neutrophils is a well-known limitation of humanized mice. Here, we generate a human granulocyte colony-stimulating factor (hG-CSF) knockin (KI) NOD/Shi-scid-IL2rgnull (NOG) mouse in which hG-CSF is systemically expressed while the mouse G-CSF receptor is disrupted. These mice generate high numbers of mature human neutrophils, which can be readily mobilized into the periphery, compared with conventional NOG mice. Moreover, these neutrophils exhibit infection-mediated emergency granulopoiesis and are capable of efficient phagocytosis and reactive oxygen species production. Thus, hG-CSF KI mice provide a useful model for studying the development of human neutrophils, emergency granulopoiesis, and a potential therapeutic model for sepsis.

Breathing-Driven Self-Powered Pyroelectric ZnO Integrated Face Mask for Bioprotection.

Rapid spread of infectious diseases is a global threat and has an adverse impact on human health, livelihood, and economic stability, as manifested in the ongoing coronavirus disease 2019 (COVID-19) pandemic. Even though people wear a face mask as protective equipment, direct disinfection of the pathogens is barely feasible, which thereby urges the development of biocidal agents. Meanwhile, repetitive respiration generates temperature variation wherein the heat is regrettably wasted. Herein, a biocidal ZnO nanorod-modified paper (ZNR-paper) composite that is 1) integrated on a face mask, 2) harvests waste breathing-driven thermal energy, 3) facilitates the pyrocatalytic production of reactive oxygen species (ROS), and ultimately 4) exhibits antibacterial and antiviral performance is proposed. Furthermore, in situ generated compressive/tensile strain of the composite by being attached to a curved mask is investigated for high pyroelectricity. The anisotropic ZNR distortion in the bent composite is verified with changes in ZnO bond lengths and OZnO bond angles in a ZnO4 tetrahedron, resulting in an increased polarization state and possibly contributing to the following pyroelectricity. The enhanced pyroelectric behavior is demonstrated by efficient ROS production and notable bioprotection. This study exploring the pre-strain effect on the pyroelectricity of ZNR-paper might provide new insights into the piezo-/pyroelectric material-based applications.

Special issue on enhanced photodynamic therapy: Part II

Special issue on enhanced photodynamic therapy: Part II

Rationally designed near-infrared AIEgens photosensitizer for cell membrane-targeted photo-driven theranostics

The complex environment of solid tumors and the migration of cancer cells are important obstacles to the cure of tumors through conventional therapy. Developing secure and efficient photosensitizers (PSs) is the crux to the application of photodynamic therapy (PDT) in the noninvasive clinical treatment of tumors. Herein, a series of PSs (DCTPys) with the same skeleton structure was designed and prepared. The unique molecular structure of DCTPys endows them with aggregation-induced emission (AIE) property and efficient reactive oxygen species (ROS) generation ability. Interestingly, due to their hydrophilic and lipophilic nature, DCTPys have fine staining and visual identification performance for the plasma membrane. In addition (e.g., MeDCTPy-OH), ROS is produced by MeDCTPy-OH under white light irradiation, which could destroy the completeness of cell membranes and cause cell necrosis. Importantly, morphology imaging of the cell membrane using MeDCTPy-OH enables real-time tracking of cancer cell ablation. This allowed cell necrosis and PDT effects to be observed under mild conditions. We conclude that DCTPys are potential cell membrane-selective PSs for PDT, and it is worth systematically exploring the phototherapeutic effect of these PSs on tumors in vivo.

Mitochondria-targeting Type I AIE photosensitizer combined with H2S therapy: Uninterrupted hydroxyl radical generation for enhancing tumor therapy

Although Type I photosensitizers with aggregation-induced emission (AIE) characteristics have thrived as alternative tools for cancer photodynamic therapy (PDT) thanks to their efficient reactive oxygen species (ROS) generation and hypoxia resistance, accumulated reducing substances sinside the tumor and the short lifespan of ROS limit their therapeutic effects. How to continuously generate long-lasting ROS in tumors remains a thorny problem. Herein, we constructed an uninterrupted ROS generator by incorporating the H2S donor, (NH4)2S, and a Type I AIE photosensitizer, TDCAc, into an injectable agarose hydrogel, namely TSH. Mitochondria-targeting TDCAc exhibited excellent performance in multi-model Type I photodynamic/photothermal therapy under near-infrared laser irradiation. While (NH4)2S generates H2S gas in the acidic tumor microenvironment upon photothermal dissolution of TSH gel, which diffuses into cancer cells and effectively inhibits intracellular catalase activity. Thus, the intrinsic H2O2 consumption pathway is blocked to promote endogenous labile iron pool-mediated continuous hydroxyl radical (·OH) generation in tumors. In both in vitro and in vivo experiments, uninterrupted massive production of·OH in cancer cells after laser irradiation of TSH gels was demonstrated. Notably, H2S gas therapy is firstly combined with Type I AIE PDT, affording a novel synergistic strategy of continuous·OH generation for boosting tumor therapy.

Responses to submergence and recovery in seedlings of the rheophyte Dyckia brevifolia (Bromeliaceae)

Complete submergence refers to the situation when floodwaters rise to levels where plants’ shoots and roots are entirely underwater. It can be viewed as a sequence of distinct stressors comprising submergence and de-submergence periods. A plant’s tolerance to this abiotic stress is determined by its ability to acclimate to both phases. Here we aimed to characterize the response of Dyckia brevifolia seedlings, a bromeliad native to Brazil, to submergence and de-submergence periods in short- and long-term stress time frames in terms of morphology, biochemistry, and gene expression. We demonstrated that D . brevifolia seedlings are tolerant to complete submergence, at least over the course of the time frame evaluated. All seedlings survived 30 d completely submerged, despite reduced dry weight and rosette area (as compared with control plants). This species adopts the low oxygen quiescence syndrome (LOQS) strategy, which comprises decreased shoot elongation underwater, downregulation of energy consumption processes, and carbohydrate catabolism (mainly starch) during the period of stress. In addition, chlorophyll and carotenoid contents were preserved, even after 1 month underwater. Furthermore, in D . brevifolia rosettes, the relative expression of hypoxia marker genes, such as alanine aminotransferase (AlaAT), pyruvate decarboxylase (PDC), and alcohol dehydrogenase (ADH), remained unchanged over the entire course of the short-term submergence stress (10 d). Mainly due to both ascorbate peroxidase (APX) and catalase (CAT) activities, this species also demonstrated an efficient reactive oxygen species (ROS)-detoxifying system, primarily for hydrogen peroxide (H 2 O 2 ), when completely submerged. During the recovery period, in addition to maintaining rosette turgidity, D . brevifolia seedlings demonstrated fast-growth resumption, total soluble sugar recovery, accumulation of chlorophyll and carotenoid, and ROS scavenging. The combination of these responses contributes to the robust adaptation of D . brevifolia to the challenging recurrent fluctuations within its unique environment. • Dyckia brevifolia seedlings adopt a quiescence strategy when submerged. • Complete submergence stress affects growth but not the survival of seedlings. • Expression of hypoxia markers genes remained unchanged during submergence. • Seedlings display key adaptive features both in submergence and de-submergence.

Preparation of Fetal Bovine Serum-Copper Phosphate Hybrid Particles under Cell Culture Conditions for Cancer Cell Treatment.

Fetal bovine serum (FBS) particles, which mainly consist of bovine serum albumin, have the potential for biological and medical applications as drug carriers. The coacervation of albumin is a common technique for preparing albumin-based particles. The replacement of salt with novel metal salts such as Cu is an affordable way to embed the metal ion in the albumin-based particles. Further, increased Cu distribution is prevalent in many cancers. Here, we prepared adhesive cell-like FBS–copper phosphate hybrid particles [FBS-Cu3(PO4)2], which exhibited toxicity toward cancer cells, with a narrow size distribution under cell culture conditions for preventing tumor progression. FBS-Cu3(PO4)2 showed peroxidase-like activity. In addition, FBS-Cu3(PO4)2 was successfully loaded with rhodamine B and conjugated with fluorescein isothiocyanate as models of drugs by coincubation. Thus, we designed a simple preparation method for optimizing FBS-Cu3(PO4)2 synthesis under cell culture conditions. FBS-Cu3(PO4)2 has significant potential as an efficient reactive oxygen species generator and drug-delivery agent against cancer cells. Furthermore, the RhoB-loaded FBS-Cu3(PO4)2 successfully interacted with 4T1 mouse mammary tumor cells and were confirmed to exhibit toxicity.

Red fluorescent AIEgens based multifunctional nonviral gene vectors for the efficient combination of gene therapy and photodynamic therapy in anti-cancer

Precise molecular engineering of AIEgens-based cationic delivery systems for high transfection efficiency (TE) and effective photodynamic therapy (PDT) holds a huge potential for cancer treatment. Herein, three amphiphiles (DT-C6/8/12-M) consisting of di(triazole-[12]aneN3) (M) and 1,1-dicyano-2-phenyl-2-(4-diphenylamino)phenyl-ethylene (DT) units have been developed to achieve luminescent tracking, efficient TE, and effective PDT in vitro and in vivo. These compounds exhibited strong aggregated induced emission (AIE) at 630 nm and mega Stokes shifts of up to 160 nm. They were able to bind DNA into nanoparticles with suitable sizes, positive surface potential, and good biocompatibility in the presence of DOPE. Among them, vector DT-C12-M/DOPE with n-dodecyl linker achieved a transfection efficiency as high as 42.3 folds that of Lipo2000 in PC-3 cell lines. DT-C12-M/DOPE exhibited the capability of successful endo/lysosomal escape and rapid nuclear delivery of pDNA, and the gene delivery process was clearly monitored via confocal laser scanning microscopy. Moreover, efficient reactive oxygen species (ROS) generation by DT-C12-M upon light irradiation led to effective PDT in vitro . We further show that combination of p53 gene therapy and PDT dramatically enhanced cancer therapeutic outcome in vivo. This “three birds, one stone” strategy offers a novel and promising approach for real-time tracking of gene delivery and better cancer treatment

Mitochondria-specific gadolinium (III) porphyrinate as efficient ROS generator for MRI visualization and sonodynamic-immunotherapy of deep localized tumors

Conventional sonodynamic therapy (SDT) is still limited in conquering localized tumors owing to its low reactive oxygen species (ROS)-based therapeutic effect and undesirably inhibiting effect of immunosuppressive tumor microenvironment (ITM). In this study, we reasonably designed a new sonosensitizer, gadolinium (III) porphyrinate (GdPorP), which could efficiently produce ROS upon ultrasound irradiation and specifically accumulate in mitochondria. The GdPorP-based mitochondria-specific sonodamage could induce high-efficiency cell apoptosis and cascade to producing large-scale immunogenic cell death. After GdPorP systematically delivered together with the indoleamine 2,3-dioxygenase (IDO) inhibitor by a pH-sensitive nanomedicine, the localized liver tumor was specifically mapped by the “switching-on” MRI. And the nanomedicine could not only efficiently suppress the progression of primary liver tumors but also simultaneously boost the systematic antitumor immune effect via the inhibition of ITM. The GdPorP-approved sonodynamic-immunotherapy (SDIT) has thereby been established as a new paradigm for upgrading the efficacy of cancer SDT.

Cover Feature: Intensifying Upconverted Ultraviolet Emission towards Efficient Reactive Oxygen Species Generation (Chem. Asian J. 15/2022)

Cover Feature: Intensifying Upconverted Ultraviolet Emission towards Efficient Reactive Oxygen Species Generation (Chem. Asian J. 15/2022)

Multifunctional amphiphilic peptide dendrimer as nonviral gene vectors for effective cancer therapy via combined gene/photodynamic therapies

Gene therapy holds great promise for treatment of gene-associated diseases. However, safe and successful clinical application urgently requires further advancement of constructing efficient delivery systems. Herein, three amphiphilic peptide dendrimers (TTC-L-KRR/KKK/KHH), containing the natural amino acid residues (lysine K, arginine R, and histidine H) and AIE-based photosensitizer (tetraphenylethenethiophene modified cyanoacrylate, TTC) modified with alkyl chain (L), have been designed and prepared for improving therapeutic potency via the combination of gene therapy (GT) and photodynamic therapy (PDT). All three compounds possessed typical aggregation-induced emission (AIE) characteristics and ultralow critical micelle concentrations (CMCs). The liposomes consisting of amphiphilic peptide dendrimers and dioleoylphosphatidylethanolamine (DOPE) can effectively bind DNA into nanoparticles with appropriate sizes, regular morphology and good biocompatibility. Among them, liposomes TTC-L-KKK/DOPE exhibited the highest transfection efficiency up to 5.7-fold as compared with Lipo2000 in HeLa cells. Meanwhile, rapid endocytosis, successful endo/lysosomal escape, gene release and rapid nuclear delivery of DNA revealed the superiority of liposomes TTC-L-KKK/DOPE during gene delivery process. More importantly, efficient reactive oxygen species (ROS) generation by TTC-L-KKK/DOPE led to effective PDT, thus improving therapeutic potency via combining with p53 mediated-gene therapy. Our work brought novel insight and direction for the construction of bio-safe and bio-imaging liposome as the multifunctional nonviral gene vectors for the effective combined gene/photodynamic therapies.

Three-Pronged Attack by Hybrid Nanoplatform Involving MXenes, Upconversion Nanoparticle and Aggregation-Induced Emission Photosensitizer for Potent Cancer Theranostics.

Inspired by the excellent photothermal conversion ability and inherent nanomedicine platform property of MXenes, efficient reactive oxygen species production and prominent fluorescence emission feature of aggregation-induced emission (AIE)-active photosensitizers (PSs), as well as the extending excitation wavelength capability of upconversion nanoparticles (UCNPs), a versatile nanoplatform comprised of Ti3 C2 nanosheets (NSs), AIE-active PSs and UCNPs is intelligently fabricated. This three-pronged strategy takes advantages of each component simultaneously, and realizes fluorescence imaging/photoacoustic imaging/photothermal imaging triple-modal imaging-guided photothermal/photodynamic synergetic therapy under 808nm laser irradiation. The introduction of UCNPs actualizes the long wavelength-activation of AIE-active PSs, which significantly increases the tissue penetration depth. Spatially isolation of AIE-active PSs and Ti3 C2 NSs is beneficial for suppressing the fluorescence quenching effect of Ti3 C2 NSs, bringing about ultimately brilliant fluorescence. The covalently bonded polymer surface endows the nanoplatform with excellent physiological stability and efficient tumor accumulation. These outputs reveal a win-win cooperation of multiple inorganic/organic nanocomposites for phototheranostics, and present great potential for future clinical translations.

Size Optimization of Organic Nanoparticles with Aggregation-Induced Emission Characteristics for Improved ROS Generation and Photodynamic Cancer Cell Ablation.

Aggregation-induced emission (AIE) fluorogens provide new opportunities to promote efficient reactive oxygen species (ROS) production in aggregates, which represent the promising candidates to construct theranostic nanoparticles for photodynamic therapy (PDT), but the size effect has been rarely explored. Herein, a universal method to fabricate organic nanoparticles with controllable sizes is reported and it demonstrates that ≈45nm is the optimal size of AIE nanoparticles for PDT. Different from conventional Ce6 nanoparticles which show largely reduced fluorescence and ROS generation with increasing nanoparticle size, AIE nanoparticles show gradually enhanced brightness and ROS generation upon increasing the sizes from 6 to ≈45nm. Further increasing sizes could continue to intensify the nanoparticle's brightness at the expense of ROS production, with the optimal size for ROS generation being achieved at ≈45nm. Both 2D monolayer cell and 3D multicellular spheroid experiments confirm that 45nm AIE nanoparticles have the highest cellular uptake, the deepest penetration depth, and the best photodynamic killing effect. Such a study not only manifests the advantages of AIE photosensitizers, but also delivers the optimal size ranging for efficient PDT, which shall provide an attractive paradigm to guide the development of phototheranostic nanoparticles besides molecular design to further promote PDT applications.

Carbon coated CoO plates/3D nickel foam: An efficient and readily recyclable catalyst for peroxymonosulfate activation

Constructing of the 3D porous structured catalyst with high efficiency and low metal ion dissolution is crucial for peroxymonosulfate (PMS) based advanced oxidation technologies (AOPs). In this work, carbon coated CoO plates/3D Ni foam catalyst was prepared by hydrothermal, carbon precursor coating and subsequently carbonization method. The obtained catalyst was further applied in the activation of PMS for the degradation of ofloxacin (OFX) and other organic pollutants in water. The physicochemical properties of the catalyst were systematically characterized, and the influence of several parameters such as catalyst and PMS dosage, initial pH and temperatures on the removal of OFX were investigated. Results showed that ∼ 100% of OFX (20 mg/L) could be degraded by the catalyst within 20 min through PMS activation. Besides, the catalyst is easy to be recovered and reused with high efficiency and low metal ion leaching. The quenching experiments and the results of EPR demonstrated both free (•OH, •SO4–, O2•–) and non-free radicals (1O2) were involved in the OFX degradation, and the cycle of Co2+/Co3+ and lattice oxygen on the catalyst surface were mainly responsible for efficient reactive oxygen species (ROS) generation from PMS. Finally, intermediate products in the OFX degradation process were identified, and possible degradation pathway and the mechanism were proposed.