Photocatalytic nonoxidative coupling of methane (CH4, NOCM) to ethane (C2H6) is a promising route for CH4 valorization, yet its efficient implementation requires the seamless coordination of CH4 adsorption, C-H bond activation, and C-C coupling. This intrinsic complexity makes it fundamentally challenging for a single type of active site to drive the entire NOCM process efficiently. Herein, we induce the formation of Ce3+ sites on the surface of CeO2 by loading Ag nanoparticles (NPs) for NOCM, and achieve highly efficient and selective conversion of CH4 to C2H6. Mechanistic studies indicate that the Ce3+ sites enhance CH4 adsorption and facilitate C-H bond activation to generate methyl radicals (˙CH3). Subsequently, Ag NPs promote the coupling of ˙CH3, ultimately producing C2H6. This study presents a synergistic catalysis strategy for designing efficient photocatalysts to achieve the selective coupling of CH4 into higher-value chemicals.

Fractal assembly in discrete structures, especially for artificial supramolecular species, has attracted significantly increased interest over the past two decades. In this study, we present the precisely controlled fractal expanding synthesis of a novel triangular prism supramolecule featuring Sierpiński triangular face, which was achieved through a module-intervened self-expansion strategy. The homoleptic S1 was firstly synthesized through the assembly of ligand L1 with Zn2+ ions. Based on the triangular-faced prism S1, we further introduced Sierpiński triangular faces on the section of the heteroleptic supramolecular cage S2 with an expanded inner cavity and more abundant active sites for photocatalytic properties. The topotactic architectures for both S1 and S2 were fully characterized by nuclear magnetic resonance spectroscopy, high-resolution electrospray ionization mass spectrometry, transmission electron microscopy, and atomic force microscopy. Furthermore, the enhanced photocatalytic activity of the fractal expanded S2 was performed via the superior amine oxidative efficiency over S1. This study proposes the unprecedented fractal expanding strategy for three-dimensional supramolecular species with higher complexity, potentially opening new avenues for structural regulation of artificial fractal molecules.

Photodynamic therapy (PDT) holds great promise for treating various types of cancer. However, its clinical advancement is hindered by the intrinsic hypoxic tumor microenvironment, which reduces PDT efficacy, and safety concerns related to the biological specificity of photosensitizers. Here we constructed a MnO2 nanosheet based DNA tetrahedron-photosensitizer (TMPyP4) nanoplatform (TPM), which integration with tumor targeting (aptamer), gene drugs (DNAzyme) and photosensitizer agents for enhanced PDT. Once the TPM entered cancer cells through aptamer targeting, the MnO2 nanosheet reacts with endogenous acidic and H2O2 to generate Mn2+ and oxygen (O2), thereby alleviating the tumor hypoxic. Subsequently, TMPyP4 further converts the generated O2 into singlet oxygen (1O2) under near-infrared light, enhancing PDT efficacy both in vitro and in vivo. Specifically, the generated Mn2+ activates the DNAzyme and accelerate tumor target mRNA cleavage, resulting in effective PDT-gene synergistic therapy for tumors. This work offers novel perspectives on advancing precise and highly effective gene-PDT systems.

Multidrug resistance (MDR) has become a major challenge in cancer therapy, it results in the failure of chemotherapy and anticancer drug development. Chemodynamic therapy (CDT), an emerging cancer treatment strategy, has been reported as a novel approach for cancer treatment characterized by low toxicity and minimal side effects. By generating robust cytotoxic hydroxyl radicals (·OH) via Fenton/Fenton-like reaction, CDT may cause cellular damage and oxidative stress-induced cell death. In recent years, many therapies based on CDT and/or combined with other treatment modalities are reported and exhibit exciting treatment efficacy in cancer treatment, such as photothermal therapy, photodynamic therapy, sonodynamic therapy, chemotherapy, starvation therapy and gas therapy etc. These combination therapies exhibit synergistic effects, significantly improving anticancer outcomes compared to CDT alone. Herein, we provide a comprehensive overview of CDT-based strategies in cancer treatment, highlighting developments of CDT and CDT-based combination strategies in tumor therapy, especially in overcoming MDR challenges. Finally, the opportunities and challenges of CDT and CDT-combination therapy in the clinical application are also addressed.

Ischemic stroke is a severe neurological disease, with high morbidity and mortality worldwide. To date, the treatment of ischemic stroke is limited, and its consequent ischemia-reperfusion injury is an important reason for this result. Excessive reactive oxygen species (ROS) and inflammatory storm followed by ischemia-reperfusion alter the microenvironment of cerebral ischemic penumbra, leading to the devastating damage to the brain. Herein, we design a black phosphorus nanosheets (BPNSs) loaded with magnesium ions (Mg2+) and polydopamine (PBP@Mg) to tackle the above problems. BPNSs of PBP@Mg effectively scavenge excessive ROS in neurocytes. Mg2+ plays an anti-inflammatory role in ischemic penumbra. Furthermore, polydopamine improves the stability of BPNSs. PBP@Mg is subsequently injected into the lateral ventricle of a rat model of ischemic stroke, resulting in an improvement of the ischemic microenvironment and a reduction in ischemic volume. BPNSs of PBP@Mg counteract against the excessive generation of ROS and the neuronal apoptosis in ischemic penumbra. Meanwhile, PBP@Mg dramatically suppresses inflammation by promoting the transformation of microglia from M1 to M2 in ischemic penumbra. PBP@Mg group exhibit a significantly better performance in neurofunctional behavior compared to ischemic group. Taken together, this study provides a novel therapeutic approach for cerebral ischemia-reperfusion injury via anti-oxidative and anti-inflammatory effects.

Precise monitoring of biomolecular radiation damage is crucial for understanding X-ray-induced cell injury and improving the accuracy of clinical radiotherapy. We present the design and performance of lanthanide-DNA-origami nanodosimeters for directly visualizing radiation damage at the single-particle level. Lanthanide ions (Tb3+ or Eu3+) coordinated with DNA origami nanosensors enhance the sensitivity of X-ray irradiation. Atomic force microscopy (AFM) revealed morphological changes in Eu3+-sensitized DNA origami upon X-ray irradiation, indicating damage caused by ionization-generated electrons and free radicals. We further demonstrated the practical applicability of Eu3+-DNA-origami integrated chips in precisely monitoring radiation-mediated cancer radiotherapy. Quantitative results showed consistent trends with flow cytometry and histological examination under comparable X-ray irradiation doses, providing an affordable and user-friendly visualization tool for preclinical applications. These findings provide new insights into the impact of heavy metals on radiation-induced biomolecular damage and pave the way for future research in developing nanoscale radiation sensors for precise clinical radiography.

An efficient method for construction of various fluorenones has been achieved via Rh(III)-catalyzed C-H activation/[4 + 2] annulation/aromatization sequences of simple and readily available enaminones and 1,3-dienes. This protocol showed good substrate compatibility as an array of structurally and electronically diverse fluorenones prepared efficiently in moderate to good yields and preparative scale utility showing very good efficiency in the late-stage functionalization of complex valuable molecules.

In the realm of electrochemiluminescence (ECL), the issue of weak signal intensity and instability linked with pure graphitic carbon nitride (CN) is widely recognized. This study suggests a method to produce nitrogen-deficient (N2C) porous ultrathin CN (UACN) using ammonium acetate and ultrasonication. The ultrathin porous nature of UACN provides numerous N2C defects as catalytic sites, aiding in the decomposition of K2S2O8, a conclusion supported by density functional theory (DFT). Importantly, N2C defects serve as electron traps, assisting in electron localization and enhancing the recombination of electron-hole pairs, thereby achieving stable and intensified luminescence from UACN. In practical use, UACN, acting as an ECL emitter, is utilized in detecting the tumor marker carcinoembryonic antigen (CEA), effectively establishing a highly sensitive immunosensing platform. This study elucidates the correlation between UACN structure and ECL performance, offering crucial insights for comprehending ECL mechanisms and designing high-performance ECL materials.

Ferroptosis, a newly discovered form of regulated cell death, has garnered significant attention in the field of tumor therapy. However, the presence of overexpressed glutathione (GSH) and insufficient levels of H2O2 in the tumor microenvironment (TME) hinders the occurrence of ferroptosis. In response to these challenges, here we have constructed the self-assembled nanocomplexes (FeE NPs) utilizing epigallocatechin-3-gallate (EGCG) from green tea polyphenols and metal ions (Fe3+) as components. After grafting PEG, the nanocomplexes (FeE@PEG NPs) exhibit good biocompatibility and synergistically enhanced tumor-inhibitory properties. FeE@PEG NPs can be disassembled by H2O2 in the TME, leading to the rapid release of Fe3+ and EGCG. The released Fe3+ produces large amounts of toxic •OH by the Fenton reactions while having minimal impact on normal cells. The generated •OH effectively induces lipid peroxidation, which leads to ferroptosis in tumor cells. Meanwhile, the released EGCG can autoxidize to produce H2O2, which further promotes the production of •OH radicals and increases lipid peroxide levels. Moreover, EGCG also depletes the high levels of intracellular GSH, leading to an intracellular redox imbalance and triggering ferroptosis. This study provides new insights into advancing anticancer ferroptosis through rational material design, offering promising avenues for future research.

In recent years, radioactive iodine capture has playedan importantrole in nuclear waste treatment. However, most of the adsorbents possesslow economic efficiency and undesirable reutilization in practicalapplication. In this work, a terpyridine-based porous metallo-organiccage was assembled for iodine adsorption. Through synchrotron X-rayanalysis, the metallo-cage was found to have a porous hierarchicalpacking mode with inherent cavity and packing channel. By taking advantageof polycyclic aromatic units and charged ⟨tpy-Zn2+-tpy⟩ (tpy = terpyridine) coordination sites in the structure,this nanocage exhibits an excellent ability to capture iodine in boththe gas phase and aqueous medium, and the crystal state of the nanocageshows an ultrafast kinetic process of capturing I-2 in aqueoussolution within 5 min. The calculated maximum sorption capacitiesfor I-2 based on the Langmuir isotherm models are 1731 and1487 mg g(-1) for amorphous and crystalline nanocages,which is noticeably higher than most of the reported iodine sorbentmaterials in the aqueous phase. This work not only provides a rareexample of iodine adsorption by a terpyridyl-based porous cage butalso expands the applications of terpyridine coordination systemsinto iodine capture.

Photodynamic therapy (PDT) has the characteristics of being simple and non-invasive, and with on-demand light control. However, most photosensitizers exhibit strong hydrophobicity, low quantum yields in water and low tumor selectivity. In this study, carbon network-hosted porphyrins (CPs) with high biocompatibility and efficient singlet oxygen (1O2) generation were developed to reduce the biotoxicity of photosensitizers and avoid quenching caused by hydrophobic aggregation for enhanced PDT. The CPs were prepared by a simple solid-phase synthesis method using porphyrin, green non-toxic citric acid and urea as the raw materials. The CPs exhibited excellent water solubility and high biocompatibility. Even when the concentration reached 1.5 mg mL-1, cells still had good biological activity. By separately fixing the porphyrins in the carbon network, the CPs avoided aggregation-induced inactivation and had high generation efficiency of 1O2. Furthermore, in order to improve the PDT effect, the CPs were modified with the upper nuclear targeting peptide TAT (T-CPs), which was used to target the nucleus and generate 1O2in situ to directly destroy genetic material. The proposed strategy provides a simple and green path to prepare nanophotosensitizers with high biocompatibility and efficient 1O2 generation for PDT.

Catalytic tumor therapy based on two-dimensional (2D) nanomaterials is a burgeoning and promising tumor therapeutic modality. However, the inefficient utilization and conversion of exogenous stimulation, single catalytic modality, and unsatisfactory therapeutic efficiency in the tumor microenvironment (TME) have seriously restricted their further application in tumor therapy. Herein, the heterogeneous carbon nitride-based nanoagent named T-HCN@CuMS was successfully developed, which dramatically improved the efficiency of the tumor therapeutic modality. Benefiting from the donor-acceptor (triazine-heptazine) structure within the heterogeneous carbon nitride nanosheets (HCN) and the construction of interplanar heterostructure with copper loaded metallic molybdenum bisulfide nanosheets (CuMS), T-HCN@CuMS presented a favorable photo-induced catalytic property to generate abundant reactive oxygen species (ROS) under near-infrared (NIR) light irradiation. Besides, the choice of CuMS simultaneously enabled this nanoagent to efficiently catalyze the Fenton-like reaction and trigger cell cuproptosis, a recently recognized regulated cell death mode characterized by imbalanced intracellular copper homeostasis and aggregation of lipoylated mitochondrial proteins. Moreover, upon surface modification with cRGDfk-PEG2k-DSPE, T-HCN@CuMS was prepared and endowed with improved dispersibility and alpha(v)beta(3) integrins targeting ability. In general, through the rational design, T-HCN@CuMS was facilely prepared and had achieved satisfactory antitumor and antimetastasis outcomes both in vitro and in a high-metastatic orthotopic osteosarcoma model. This strategy could offer an idea to treat malignant diseases based on 2D nanomaterials.

The printing ink on the plastic surface will greatly reduce the quality of recycled plastic products. In this work, quaternary ammonium-modified waste cooking oil (WCOEQ) was fabricated using waste cooking oil, epichlorohydrin, and trimethylamine aqueous solution as raw materials, through ring-opening esterification and quaternary amination reaction. The synthesis conditions of WCOEQ were optimised, and the structure and properties of WCOEQ were characterised by Fourier transform infrared spectroscopy, zeta potential, and 1H NMR. Furthermore, WCOEQ had excellent emulsifying performance, low kraft point, low critical micelle concentration value, good foaming, and stability, which could effectively reduce the surface tension of water, showing application potential in the field of plastic deinking. Importantly, compared with the waste cooking oil without deinking effect, the WCOEQ had an excellent deinking performance on the ink on the plastic surface, and the deinking efficiency could be improved by increasing the concentration of the deinking agent, the deinking temperature, and prolonging the pre-soaking and stirring time. The results of atomic force microscope, energy-dispersive spectroscopy, optical photos, and Leica microscope showed that the roughness changed significantly and the ink molecules were gradually peeling off. This work highlighted the potential of quaternary ammonium-modified waste cooking oil for excellent removal of printing inks on the plastic surface.

In personalized cancer immunotherapy, developing an effective neoantigen nanovaccine with high immunogenicity is a significant challenge. Traditional nanovaccine delivery systems often require nanocarriers, which can hinder the delivery of the neoantigen and cause significant toxicity. In this study, we present an innovative strategy of carrier-free nanovaccine achieved through direct self-assembly of 2'-fluorinated CpG (2'F-CpG) with melanoma neoantigen peptide (Obsl1). Molecular dynamics simulations demonstrated that the introduction of a fluorine atom into CpG increases the noncovalent interaction between 2'F-CpG and Obsl1, which enhanced the loading of Obsl1 on 2'F-CpG, resulting in the spontaneous formation of a hybrid 2'F-CpG/Obsl1 nanovaccine. This nanovaccine without extra nanocarriers showed ultrahigh Obsl1 loading up to 83.19 wt %, increasing the neoantigen peptide uptake by antigen-presenting cells (APCs). In C57BL/6 mice models, we demonstrated the long-term preventive and therapeutic effects of the prepared 2'F-CpG/Obsl1 nanovaccine against B16F10 melanoma. Immunocellular analysis revealed that the nanovaccine activated innate and adaptive immune responses to cancer cells. Hence, this study established a simple, safe, and effective preparation strategy for a carrier-free neoantigen nanovaccine, which could be adapted for the future design of personalized cancer vaccines in clinical settings.

Multiple drug-resistance mechanisms originate from defensive pathways in cancer and are associated with the unsatisfied efficacy of chemotherapy. The combination of small interfering RNA (siRNA) and chemotherapeutics provides a strategy for reducing drug efflux but requires more delivery options for clinical translation. Herein, multidrug resistance protein 1 (MDR1) siRNA is used as the skeleton to assemble chemotherapeutic cisplatin (CDDP) and divalent copper ion (Cu2+) for constructing a carrier-free Cu-siMDR-CDDP system. Cu-siMDR-CDDP specifically responds and disassembles in the acidic tumor microenvironment (TME). The released CDDP activates cascade bioreactions of NADPH oxidases and superoxide dismutase to generate hydrogen peroxide (H2O2). Then a Cu2+-catalyzed Fenton-like reaction transforms H2O2 to hydroxyl radicals (HO•) and causes glutathione (GSH) depletion to disrupt the redox adaptation mechanism of drug-resistant cancer cells. Besides, delivery of MDR1 siRNA is facilitated by HO•-triggered lysosome destruction, thus inhibiting P-glycoprotein (P-gp) expression and CDDP efflux. The unique design of Cu-siMDR-CDDP is to exploit siRNA as building blocks in regulating the self-assembly behavior, and integration of functional units simultaneously alleviates limitations caused by drug-resistance mechanisms. Such a carrier-free system shows synergistic chemo/chemodynamic/RNA interference therapy in suppressing tumor growth in vivo and has the reference value for overcoming drug resistance.

With simple alkanes as the alkyl radical precursors under microwave irradiation, a convenient and efficient cross-dehydrogenative alkylation reaction of quinoxalin-2(1H)-ones and other N-heteroarenes has been achieved. The protocol demonstrates a broad substrate scope, good functional group tolerance, high atom economy and high efficiency, providing a wide range of valuable, structurally diverse C3 alkylated quinoxalin-2(1H)-ones and other alkylated N-heteroarenes in good-to-excellent yields.

Photodynamic therapy (PDT) has been showing great potential in cancer treatment. However, the efficacy of PDT is always limited by the intrinsic hypoxic tumor microenvironment (TME) and the low accumulation efficiency of photosensitizers in tumors. To address the issue, a multifunctional hollow multilayer nanoplatform (H-MnO2 @TPyP@Bro) comprising manganese dioxide, porphyrin (TPyP) and bromelain (Bro), is developed for enhanced photodynamic therapy. MnO2 catalyzes the intracellular hydrogen peroxide (H2 O2 ) to produce oxygen (O2 ), reversing the hypoxic TME in vivo. The generated O2 is converted into singlet oxygen (1 O2 ) by the TPyP shell under near-infrared light, which can inhibit tumor proliferation. Meanwhile, the Bro can digest collagen in the extracellular matrix around the tumor, and can promote the accumulation of H-MnO2 @TPyP@Bro in the deeper tumor tissue, further improving the therapeutic effect of PDT. In addition, MnO2 can react with the overexpressed glutathione in TME to release Mn2+ . Consequently, Mn2+ not only induces chemo-dynamic therapy based on Fenton reaction by converting H2 O2 into hydroxyl radicals, but also activates the Mn2+ -based magnetic resonance imaging. Therefore, the developed H-MnO2 @TPyP@Bro nanoplatform can effectively modulate the unfavorable TME and overcome the limitations of conventional PDT for cancer diagnostic and therapeutic.

Responsive nano-drug delivery systems, especially multi-responsive systems, based on the complex characteristics of the tumor microenvironment (TME), such as acidic pH, hypoxia, and hydrogen peroxide (H2O2) overexpression, could enhance the biological activity of the drugs and reduce the side effects. In this study, a H2O2/glutathione (GSH) procedurally activatable nanoplatform (Cu9S5-PEG/DOX NSs) was prepared as a vector of drugs released by responsive morphologic transformation and the co-activated Fenton agent for tumor-specific synergistic therapy. After endocytosis into tumor cells, Cu9S5-PEG/DOX NSs were initially oxidized by over-expressed H2O2 and transformed from nanosheets to nanoflowers, leading to the release of doxorubicin (DOX). Subsequently, Cu9S5 nanoflowers (Cu9S5 NFs) reacted with the local GSH, liberated a large number of copper ions, and induced GSH depletion. The released DOX promoted the generation of intracellular H2O2 through cascade reactions, which were further utilized to facilitate the release of DOX and generate toxic hydroxyl radicals (˙OH) via a copper-based Fenton-like reaction. Cu9S5-PEG/DOX NSs sequentially activated by H2O2 and GSH in tumor cells exhibited relatively high cytotoxicity, whereas normal cells were still alive. This nanoplatform, as a procedurally activatable delivery system, may have excellent potential for tumor-specific synergistic therapy.

Accurate detection and imaging of low-abundance microRNA (miRNA) in living cells are essential for the diagnosis and prognosis of diseases. Designing nanoprobes with resistance to enzyme degradation, effective cell-binding, and efficient signal amplification is crucial for in vivo imaging. In this study, we present an aptamer-tethered DNA origami amplifier (ADOA) that functions inside living cells to detect miRNA with high sensitivity and stability. In the design, cancer cell-targeting aptamers were tethered onto the border of the DNA origami to improve the discrimination between cancer cells and normal cells. Two substrate modules for the intramolecular entropy-driven reaction (EDR) circuit were alternately arranged on the DNA origami plane. The target miRNA will initiate the sequential hybridization of the two substrate modules on the DNA origami, generating amplified fluorescence signals. The proposed ADOA achieved an accelerated cascade reaction due to the "confinement effect" and significantly enhanced the sensitivity compared with a traditional EDR. Meanwhile, with the rigid structure of the DNA origami, the ADOA possessed excellent signalling stability in living cells. Therefore, the ADOA could expand the application of DNA origami in miRNA sensing and has potential value in early-stage clinical diagnosis.

Chemotherapy assisted by carbon monoxide (CO) gas therapy is an emerging powerful cancer therapeutic modality. However, the effective delivery and controlled release of CO in tumor cells remain a challenge. Herein, a cell membrane bionic nano delivery system (RBC-H@DOX/3-HF@MSN, termed as RHM) was designed to selectively accumulate in tumors and generate CO in situ upon red light irradiation for the combination of chemotherapy and gas therapy. CO significantly improves the therapeutic effect of DOX from 29.0% to 82.4%.