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1.
Fenton reaction‐mediated chemodynamic therapy (CDT) can kill cancer cells via the conversion of H2O2 to highly toxic HO?. However, problems such as insufficient H2O2 levels in the tumor tissue and low Fenton reaction efficiency severely limit the performance of CDT. Here, the prodrug tirapazamine (TPZ)‐loaded human serum albumin (HSA)–glucose oxidase (GOx) mixture is prepared and modified with a metal–polyphenol network composed of ferric ions (Fe3+) and tannic acid (TA), to obtain a self‐amplified nanoreactor termed HSA–GOx–TPZ–Fe3+–TA (HGTFT) for sustainable and cascade cancer therapy with exogenous H2O2 production and TA‐accelerated Fe3+/Fe2+ conversion. The HGTFT nanoreactor can efficiently convert oxygen into HO? for CDT, consume glucose for starvation therapy, and provide a hypoxic environment for TPZ radical‐mediated chemotherapy. Besides, it is revealed that the nanoreactor can significantly elevate the intracellular reactive oxygen species content and hypoxia level, decrease the intracellular glutathione content, and release metal ions in the tumors for metal ion interference therapy (also termed “ion‐interference therapy” or “metal ion therapy”). Further, the nanoreactor can also increase the tumor’s hypoxia level and efficiently inhibit tumor growth. It is believed that this tumor microenvironment‐regulable nanoreactor with sustainable and cascade anticancer performance and excellent biosafety represents an advance in nanomedicine.  相似文献   

2.
The tumor microenvironment (TME) has been increasingly recognized as a crucial contributor to tumorigenesis. Based on the unique TME for achieving tumor‐specific therapy, here a novel concept of photothermal‐enhanced sequential nanocatalytic therapy in both NIR‐I and NIR‐II biowindows is proposed, which innovatively changes the condition of nanocatalytic Fenton reaction for production of highly efficient hydroxyl radicals (?OH) and consequently suppressing the tumor growth. Evidence suggests that glucose plays a vital role in powering cancer progression. Encouraged by the oxidation of glucose to gluconic acid and H2O2 by glucose oxidase (GOD), an Fe3O4/GOD‐functionalized polypyrrole (PPy)‐based composite nanocatalyst is constructed to achieve diagnostic imaging‐guided, photothermal‐enhanced, and TME‐specific sequential nanocatalytic tumor therapy. The consumption of intratumoral glucose by GOD leads to the in situ elevation of the H2O2 level, and the integrated Fe3O4 component then catalyzes H2O2 into highly toxic ?OH to efficiently induce cancer‐cell death. Importantly, the high photothermal‐conversion efficiency (66.4% in NIR‐II biowindow) of the PPy component elevates the local tumor temperature in both NIR‐I and NIR‐II biowindows to substaintially accelerate and improve the nanocatalytic disproportionation degree of H2O2 for enhancing the nanocatalytic‐therapeutic efficacy, which successfully achieves a remarkable synergistic anticancer outcome with minimal side effects.  相似文献   

3.
The exploitation of photocatalysts that harvest solar spectrum as broad as possible remains a high‐priority target yet grand challenge. In this work, for the first time, metal–organic framework (MOF) composites are rationally fabricated to achieve broadband spectral response from UV to near‐infrared (NIR) region. In the core–shell structured upconversion nanoparticles (UCNPs)‐Pt@MOF/Au composites, the MOF is responsive to UV and a bit visible light, the plasmonic Au nanoparticles (NPs) accept visible light, whereas the UCNPs absorb NIR light to emit UV and visible light that are harvested by the MOF and Au once again. Moreover, the MOF not only facilitates the generation of “bare and clean” Au NPs on its surface and realizes the spatial separation for the Au and Pt NPs, but also provides necessary access for catalytic substrates/products to Pt active sites. As a result, the optimized composite exhibits excellent photocatalytic hydrogen production activity (280 µmol g?1 h?1) under simulated solar light, and the involved mechanism of photocatalytic H2 production under UV, visible, and NIR irradiation is elucidated. Reportedly, this is an extremely rare study on photocatalytic H2 production by light harvesting in all UV, visible, and NIR regions.  相似文献   

4.
Previously, a large volume of papers reports that gold nanorods (Au NRs) are able to effectively kill cancer cells upon high laser doses (usually 808 nm, 1–48 W/cm2) irradiation, leading to hyperthermia‐induced destruction of cancer cells, i.e, photothermal therapy (PTT) effects. Combination of Au NRs‐mediated PTT and organic photosensitizers‐mediated photodynamic therapy (PDT) were also reported to achieve synergistic PTT and PDT effects on killing cancer cells. Herein, we demonstrate for the first time that Au NRs alone can sensitize formation of singlet oxygen (1O2) and exert dramatic PDT effects on complete destrcution of tumors in mice under very low LED/laser doses of single photon NIR (915 nm, <130 mW/cm2) light excitation. By changing the NIR light excitation wavelengths, Au NRs‐mediated phototherapeutic effects can be switched from PDT to PTT or combination of both. Both PDT and PTT effects were confirmed by measurements of reactive oxygen species (ROS) and heat shock protein (HSP 70), singlet oxygen sensor green (SOSG) sensing, and sodium azide quenching in cellular experiments. In vivo mice experiments further show that the PDT effect via irradiation of Au NRs by 915 nm can destruct the B16F0 melanoma tumor in mice far more effectively than doxorubicin (a clinically used anti‐cancer drug) as well as the PTT effect (via irradiation of Au NRs by 780 nm light). In addition, we show that Au NRs can emit single photon‐induced fluorescence to illustrate their in vivo locations/distribution.  相似文献   

5.
Synthetic biology based on bacteria has been displayed in antitumor therapy and shown good performance. In this study, an engineered bacterium Escherichia coli MG1655 is designed with NDH‐2 enzyme (respiratory chain enzyme II) overexpression (Ec‐pE), which can colonize in tumor regions and increase localized H2O2 generation. Following from this, magnetic Fe3O4 nanoparticles are covalently linked to bacteria to act as a catalyst for a Fenton‐like reaction, which converts H2O2 to toxic hydroxyl radicals (?OH) for tumor therapy. In this constructed bioreactor, the Fenton‐like reaction occurs with sustainably synthesized H2O2 produced by engineered bacteria, and severe tumor apoptosis is induced via the produced toxic ?OH. These results show that this bioreactor can achieve effective tumor colonization, and realize a self‐supplied therapeutic Fenton‐like reaction without additional H2O2 provision.  相似文献   

6.
Photoimmunotherapy can not only effectively ablate the primary tumor but also trigger strong antitumor immune responses against metastatic tumors by inducing immunogenic cell death. Herein, Cu2MoS4 (CMS)/Au heterostructures are constructed by depositing plasmonic Au nanoparticles onto CMS nanosheets, which exhibit enhanced absorption in near‐infrared (NIR) region due to the newly formed mid‐gap state across the Fermi level based on the hybridization between Au 5d orbitals and S 3p orbitals, thus resulting in more excellent photothermal therapy and photodynamic therapy (PDT) effect than single CMS upon NIR laser irradiation. The CMS and CMS/Au can also serve as catalase to effectively relieve tumor hypoxia, which can enhance the therapeutic effect of O2‐dependent PDT. Notably, the NIR laser‐irradiated CMS/Au can elicit strong immune responses via promoting dendritic cells maturation, cytokine secretion, and activating antitumor effector T‐cell responses for both primary and metastatic tumors eradication. Moreover, CMS/Au exhibits outstanding photoacoustic and computed tomography imaging performance owing to its excellent photothermal conversion and X‐ray attenuation ability. Overall, the work provides an imaging‐guided and phototherapy‐induced immunotherapy based on constructing CMS/Au heterostructures for effectively tumor ablation and cancer metastasis inhibition.  相似文献   

7.
Chemodynamic therapy (CDT) has attracted considerable attention recently, but the poor reaction kinetics restrict its practical utility in clinic. Herein, glucose oxidase (GOx) functionalized ancient pigment nanosheets (SrCuSi4O10, SC) for programmable near‐infrared II (NIR‐II) photothermal‐enhanced starvation primed CDT is developed. The SC nanosheets (SC NSs) are readily exfoliated from SC bulk suspension in water and subsequently functionalized with GOx to form the nanocatalyst (denoted as SC@G NSs). Upon laser irradiation, the photothermal effect of SC NSs can enhance the catalytic activity of GOx for NIR‐II photothermal‐enhanced starvation therapy, which effectively eliminates intratumoral glucose and produces abundant hydrogen peroxide (H2O2). Importantly, the high photothermal‐conversion efficiency (46.3%) of SC@G NSs in second biological window permits photothermal therapy of deep‐seated tumors under the guidance of NIR‐II photoacoustic imaging. Moreover, the acidity amplification due to gluconic acid generation will in turn accelerate the degradation of SC NSs, facilitating the release of strontium (Sr) and copper (Cu) ions. Both the elevated H2O2 and the released ions will prime the Cu2+/Sr2+‐H2O2 reaction for enhanced CDT. Thus, a programmable NIR‐II photothermal‐enhanced starvation primed CDT is established to combat cancer with minimal side effects.  相似文献   

8.
DNA‐mediated assembly of core–satellite structures composed of Zr(IV)‐based porphyrinic metal‐organic framework (MOF) and NaYF4,Yb,Er upconverting nanoparticles (UCNPs) for photodynamic therapy (PDT) is reported. MOF NPs generate singlet oxygen (1O2) upon photoirradiation with visible light without the need for additional small molecule, diffusional photosensitizers such as porphyrins. Using DNA as a templating agent, well‐defined MOF–UCNP clusters are produced where UCNPs are spatially organized around a centrally located MOF NP. Under NIR irradiation, visible light emitted from the UCNPs is absorbed by the core MOF NP to produce 1O2 at significantly greater amounts than what can be produced from simply mixing UCNPs and MOF NPs. The MOF–UCNP core–satellite superstructures also induce strong cell cytotoxicity against cancer cells, which are further enhanced by attaching epidermal growth factor receptor targeting affibodies to the PDT clusters, highlighting their promise as theranostic photodynamic agents.  相似文献   

9.
Cancer cells are susceptible to oxidative stress; therefore, selective elevation of intracellular reactive oxygen species (ROS) is considered as an effective antitumor treatment. Here, a liposomal formulation of dichloroacetic acid (DCA) and metal–organic framework (MOF)‐Fe2+ (MD@Lip) has been developed, which can efficiently stimulate ROS‐mediated cancer cell apoptosis in vitro and in vivo. MD@Lip can not only improve aqueous solubility of octahedral MOF‐Fe2+, but also generate an acidic microenvironment to activate a MOF‐Fe2+‐based Fenton reaction. Importantly, MD@Lip promotes DCA‐mediated mitochondrial aerobic oxidation to increase intracellular hydrogen peroxide (H2O2), which can be consequently converted to highly cytotoxic hydroxyl radicals (?OH) via MOF‐Fe2+, leading to amplification of cancer cell apoptosis. Particularly, MD@Lip can selectively accumulate in tumors, and efficiently inhibit tumor growth with minimal systemic adverse effects. Therefore, liposome‐based combination therapy of DCA and MOF‐Fe2+ provides a promising oxidative stress–associated antitumor strategy for the management of malignant tumors.  相似文献   

10.
Photodynamic therapy (PDT), which relies on photosensitizers (PS) and light to generate reactive oxygen species to kill cancer cells or bacteria, has attracted much attention in recent years. PSs with both bright emission and efficient singlet oxygen generation have also been used for image‐guided PDT. However, simultaneously achieving effective 1O2 generation, long wavelength absorption, and stable near‐infrared (NIR) emission with low dark toxicity in a single PS remains challenging. In addition, it is well known that when traditional PSs are made into nanoparticles, they encounter quenched fluorescence and reduced 1O2 production. In this contribution, these challenging issues have been successfully addressed through designing the first photostable photosensitizer with aggregation‐induced NIR emission and very effective 1O2 generation in aggregate state. The yielded nanoparticles show very effective 1O2 generation, bright NIR fluorescence centered at 820 nm, excellent photostability, good biocompatibility, and negligible dark in vivo toxicity. Both in vitro and in vivo experiments prove that the nanoparticles are excellent candidates for image‐guided photodynamic anticancer therapy.  相似文献   

11.
Here a multifunctional nanoplatform (upconversion nanoparticles (UCNPs)‐platinum(IV) (Pt(IV))?ZnFe2O4, denoted as UCPZ) is designed for collaborative cancer treatment, including photodynamic therapy (PDT), chemotherapy, and Fenton reaction. In the system, the UCNPs triggered by near‐infrared light can convert low energy photons to high energy ones, which act as the UV–vis source to simultaneously mediate the PDT effect and Fenton's reaction of ZnFe2O4 nanoparticles. Meanwhile, the Pt(IV) prodrugs can be reduced to high virulent Pt(II) by glutathione in the cancer cells, which can bond to DNA and inhibit the copy of DNA. The synergistic therapeutic effect is verified in vitro and in vivo results. The cleavage of Pt(IV) from UCNPs during the reduction process can shift the larger UCPZ nanoparticles (NPs) to the smaller ones, which promotes the enhanced permeability and retention (EPR) and deep tumor penetration. In addition, due to the inherent upconversion luminescence (UCL) and the doped Yb3+ and Fe3+ in UCPZ, this system can serve as a multimodality bioimaging contrast agent, covering UCL, X‐ray computed tomography, magnetic resonance imaging, and photoacoustic. A smart all‐in‐one imaging‐guided diagnosis and treatment system is realized, which should have a potential value in the treatment of tumor.  相似文献   

12.
Inhibition of protein biosynthesis is a promising strategy to develop new therapeutic modalities for cancers; however, noninvasive precise regulation of this cellular event in living systems has been rarely reported. In this study, a semiconducting polymer nanoblockader (SPNB) is developed that can inhibit intracellular protein synthesis upon near‐infrared (NIR) photoactivation to synergize with photodynamic therapy (PDT) for metastasis‐inhibited cancer therapy. SPNB is self‐assembled from an amphiphilic semiconducting polymer which is grafted with poly(ethylene glycol) conjugated with a protein biosynthesis blockader through a singlet oxygen (1O2) cleavable linker. Such a designed molecular structure not only enables generation of 1O2 under NIR photoirradiation for PDT, but also permits photoactivation of blockaders to terminate protein translation. Thereby, SPNB exerts a synergistic action to afford an enhanced therapeutic efficacy in tumor ablation. More importantly, SPNB‐mediated photoactivation of protein synthesis inhibition precisely and remotely downregulates the expression levels of metastasis‐related proteins in tumor tissues, eventually contributing to the complete inhibition of lung metastasis. This study thus proposes a photoactivatable protherapeutic design for metastasis‐inhibited cancer therapy.  相似文献   

13.
Complex multiphase nanocomposite designs present enormous opportunities for developing next‐generation integrated photonic and electronic devices. Here, a unique three‐phase nanostructure combining a ferroelectric BaTiO3, a wide‐bandgap semiconductor of ZnO, and a plasmonic metal of Au toward multifunctionalities is demonstrated. By a novel two‐step templated growth, a highly ordered Au–BaTiO3–ZnO nanocomposite in a unique “nanoman”‐like form, i.e., self‐assembled ZnO nanopillars and Au nanopillars in a BaTiO3 matrix, is realized, and is very different from the random three‐phase ones with randomly arranged Au nanoparticles and ZnO nanopillars in the BaTiO3 matrix. The ordered three‐phase “nanoman”‐like structure provides unique functionalities such as obvious hyperbolic dispersion in the visible and near‐infrared regime enabled by the highly anisotropic nanostructures compared to other random structures. Such a self‐assembled and ordered three‐phase nanocomposite is obtained through a combination of vapor–liquid–solid (VLS) and two‐phase epitaxy growth mechanisms. The study opens up new possibilities in the design, growth, and application of multiphase structures and provides a new approach to engineer the ordering of complex nanocomposite systems with unprecedented control over electron–light–matter interactions at the nanoscale.  相似文献   

14.
As emerging efficient emitters, metal‐halide perovskites offer the intriguing potential to the low‐cost light emitting devices. However, semiconductors generally suffer from severe luminescence quenching due to insufficient confinement of excitons (bound electron–hole pairs). Here, Sn‐triggered extrinsic self‐trapping of excitons in bulk 2D perovskite crystal, PEA2PbI4 (PEA = phenylethylammonium), is reported, where exciton self‐trapping never occurs in its pure state. By creating local potential wells, isoelectronic Sn dopants initiate the localization of excitons, which would further induce the large lattice deformation around the impurities to accommodate the self‐trapped excitons. With such self‐trapped states, the Sn‐doped perovskites generate broadband red‐to‐near‐infrared (NIR) emission at room temperature due to strong exciton–phonon coupling, with a remarkable quantum yield increase from 0.7% to 6.0% (8.6 folds), reaching 42.3% under a 100 mW cm?2 excitation by extrapolation. The quantum yield enhancement stems from substantial higher thermal quench activation energy of self‐trapped excitons than that of free excitons (120 vs 35 meV). It is further revealed that the fast exciton diffusion involves in the initial energy transfer step by transient absorption spectroscopy. This dopant‐induced extrinsic exciton self‐trapping approach paves the way for extending the spectral range of perovskite emitters, and may find emerging application in efficient supercontinuum sources.  相似文献   

15.
Radioisotope therapy (RIT), in which radioactive agents are administered or implanted into the body to irradiate tumors from the inside, is a clinically adopted cancer treatment method but still needs improvement to enhance its performances. Herein, it is found that polyethylene glycol (PEG) modified tungsten disulfide (WS2) nanoflakes can be easily labeled by 188Re, a widely used radioisotope for RIT, upon simple mixing. Like other high‐Z elements acting as radiosensitizers, tungsten in the obtained 188Re‐WS2‐PEG would be able to absorb ionization radiation generated from 188Re, enabling ‘‘self‐sensitization’’ to enhance the efficacy of RIT as demonstrated in carefully designed in vitro experiments of this study. In the meanwhile, the strong NIR absorbance of WS2‐PEG could be utilized for NIR light‐induced photothermal therapy (PTT), which if applied on tumors would be able to greatly relieve their hypoxia state and help to overcome hypoxia‐associated radioresistance of tumors. Therefore, with 188Re‐WS2‐PEG as a multifunctional agent, which shows efficient passive tumor homing after intravenous injection, in vivo self‐sensitized, NIR‐enhanced RIT cancer treatment is realized, achieving excellent tumor killing efficacy in a mouse tumor model. This work presents a new concept of applying nanotechnology in RIT, by delivering radioisotopes into tumors, self‐sensitizing the irradiation‐induced cell damage, and modulating the tumor hypoxia state to further enhance the therapeutic outcomes.  相似文献   

16.
High‐performance and inexpensive platinum‐group‐metal (PGM)‐free catalysts for the oxygen reduction reaction (ORR) in challenging acidic media are crucial for proton‐exchange‐membrane fuel cells (PEMFCs). Catalysts based on Fe and N codoped carbon (Fe–N–C) have demonstrated promising activity and stability. However, a serious concern is the Fenton reactions between Fe2+ and H2O2 generating active free radicals, which likely cause degradation of the catalysts, organic ionomers within electrodes, and polymer membranes used in PEMFCs. Alternatively, Co–N–C catalysts with mitigated Fenton reactions have been explored as a promising replacement for Fe and PGM catalysts. Therefore, herein, the focus is on Co–N–C catalysts for the ORR relevant to PEMFC applications. Catalyst synthesis, structure/morphology, activity and stability improvement, and reaction mechanisms are discussed in detail. Combining experimental and theoretical understanding, the aim is to elucidate the structure–property correlations and provide guidance for rational design of advanced Co catalysts with a special emphasis on atomically dispersed single‐metal‐site catalysts. In the meantime, to reduce H2O2 generation during the ORR on the Co catalysts, potential strategies are outlined to minimize the detrimental effect on fuel cell durability.  相似文献   

17.
Engineering functional nanomaterials with high therapeutic efficacy and minimum side effects has increasingly become a promising strategy for cancer treatment. Herein, a reactive oxygen species (ROS) enhanced combination chemotherapy platform is designed via a biocompatible metal‐polyphenol networks self‐assembly process by encapsulating doxorubicin (DOX) and platinum prodrugs in nanoparticles. Both DOX and platinum drugs can activate nicotinamide adenine dinucleotide phosphate oxidases, generating superoxide radicals (O2??). The superoxide dismutase‐like activity of polyphenols can catalyze H2O2 generation from O2??. Finally, the highly toxic HO? free radicals are generated by a Fenton reaction. The ROS HO? can synergize the chemotherapy by a cascade of bioreactions. Positron emission tomography imaging of 89Zr‐labeled as‐prepared DOX@Pt prodrug Fe3+ nanoparticles (DPPF NPs) shows prolonged blood circulation and high tumor accumulation. Furthermore, the DPPF NPs can effectively inhibit tumor growth and reduce the side effects of anticancer drugs. This study establishes a novel ROS promoted synergistic nanomedicine platform for cancer therapy.  相似文献   

18.
Self‐propelled micromachines have recently attracted lots of attention for environmental remediation. Developing a large‐scale but template‐free fabrication of self‐propelled rod/tubular micro/nanomotors is very crucial but still challenging. Here, a new strategy based on vertically aligned ZnO arrays is employed for the large‐scale and template‐free fabrication of self‐propelled ZnO‐based micromotors with H2O2‐free light‐driven propulsion ability. Brush‐shaped ZnO‐based micromotors with different diameters and lengths are fully studied, which present a fast response to multicycles UV light on/off switches with different interval times (2/5 s) in pure water and slow directional motion in aqueous hydrogen peroxide solution in the absence of UV light. Light‐induced electrophoretic and self‐diffusiophoretic effects are responsible for these two different self‐motion behaviors under different conditions, respectively. In addition, the pH of the media and the presence of H2O2 show important effects on the motion behavior and microstructure of the ZnO‐based micromotors. Finally, these novel ZnO‐based brush‐shaped micromotors are demonstrated in a proof‐of‐concept study on nitroaromatic explosive degradation, i.e., picric acid. This work opens a completely new avenue for the template‐free fabrication of brush‐shaped light‐responsive micromotors on a large scale based on vertically aligned ZnO arrays.  相似文献   

19.
Inspired by bio‐enzymes, multistep cascade reactions are highly attractive in catalysis. Despite extensive research in recent years, it remains a challenge to promote the stability and activity of catalysts. Here, well‐defined core–shell structured Ag–Au nanocage@CeO2 (Ag–Au NC@CeO2) are designed by a simple and facile self‐assembly method. The results indicate that the Ag–Au NC@CeO2 has glucose oxidase‐like activity and intrinsic peroxidase‐like activity at the same time. As expected, Ag–Au NC@CeO2 hybrid nanomaterials exhibit cascade reactions activity. Moreover, the hybrid materials are promising to detect glucose without bio‐enzymes. This research has potential applications in biomedicine and biomimetic catalysis.  相似文献   

20.
The unique tumor microenvironment (TME) facilitates cancer proliferation and metastasis, and it is hard to cure cancer completely via monotherapy. Herein, a multifunctional cascade bioreactor based on hollow mesoporous Cu2MoS4 (CMS) loaded with glucose oxidase (GOx) is constructed for synergetic cancer therapy by chemo‐dynamic therapy (CDT)/starvation therapy/phototherapy/immunotherapy. The CMS harboring multivalent elements (Cu1+/2+, Mo4+/6+) exhibit Fenton‐like, glutathione (GSH) peroxidase‐like and catalase‐like activity. Once internalized into the tumor, CMS could generate ·OH for CDT via Fenton‐like reaction and deplete overexpressed GSH in TME to alleviate antioxidant capability of the tumors. Moreover, under hypoxia TME, the catalase‐like CMS could react with endogenous H2O2 to generate O2 for activating the catalyzed oxidation of glucose by GOx for starvation therapy accompanied with the regeneration of H2O2. The regenerated H2O2 can devote to Fenton‐like reaction for realizing GOx‐catalysis‐enhanced CDT. Meanwhile, the CMS under 1064 nm laser irradiation shows remarkable tumor‐killing ability by phototherapy due to its excellent photothermal conversion efficiency (η = 63.3%) and cytotoxic superoxide anion (·O2?) generation performance. More importantly, the PEGylated CMS@GOx‐based synergistic therapy combined with checkpoint blockade therapy could elicit robust immune responses for both effectively ablating primary tumors and inhibiting cancer metastasis.  相似文献   

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