Urchin-Shaped Metal Organic/Hydrogen-Bonded Framework Nanocomposite as a Multifunctional Nanoreactor for Catalysis-Enhanced Synergetic Therapy

Emerging glucose oxidase-delivering nanomedicines for enhanced tumor therapy

Abnormalities in glucose metabolism have been shown to characterize malignant tumors. Glucose depletion by glucose oxidase (GOD) has shown great potential in tumor therapy by causing tumor starvation. Since 2017, nanomedicines have been designed and utilized to deliver GOD for more precise and effective glucose modulation, which can overcome intrinsic limitations of different cancer therapeutic modalities by remodeling the tumor microenvironment to enhance antitumor therapy. To date, the topic of GOD-delivering nanomedicines for enhancing tumor therapy has not been comprehensively summarized. Herein, this review aims to provide an overview and discuss in detail recent advances in GOD delivery and directly involved starvation therapy strategies, GOD-sensitized various tumor therapy strategies, and GOD-mediated multimodal antitumor strategies. Finally, the challenges and outlooks for the future progress of the emerging tumor therapeutic nanomedicines are discussed. This review provides intuitive and specific insights to a broad audience in the fields of nanomedicines, biomaterials, and cancer therapy.

Application of pyrene-based HOFs in ethyl cellulose-based food packaging films

This study investigates the application of pyrene-based HOFs in ethyl cellulose (EC)-based food packaging films. As the environmental impact of traditional plastics becomes increasingly significant, the development of environmentally friendly food packaging materials is urgent. The study synthesized two types of HOFs, HOF-PyTTA and PFC-2, which were fabricated into EC-HOFs composite films using a solution casting method. These composite films not only demonstrate excellent biocompatibility and hemocompatibility but also exhibit significantly enhanced UV shielding effects and antioxidant properties. In particular, EC-HOF-PyTTA-1 % film shows the best UV shielding effect (70.3 %) and antioxidant performance (31.8 %), and it also possesses a fluorescence angle-dependent color change function. The study indicates that the introduction of HOFs significantly improves the mechanical properties and thermal stability of EC films, providing new insights for the green design of food packaging materials.

Heterogeneous piezo-self-Fenton material design: an intersecting solution for pollutant degradation and tumor therapy

Heterogeneous piezo-self-Fenton (EPSF), an integration of piezocatalysis and heterogeneous Fenton reactions, forms the foundation for efficient redox interfacial reactions in complex environments. The significant generation of reactive oxygen species (ROS) during the catalytic process and the mechanical energy-driven nature of the EPSF process provide distinct advantages in environmental remediation and biomedical applications. Numerous studies on EPSF catalysts have emerged in recent years across these fields. However, the construction approaches and design strategies for EPSF catalysts in various application scenarios remain unclear. This review synthesizes and analyzes studies on organic pollutant degradation and targeted tumor therapy. Based on the elucidation of redox processes in EPSF catalysis, the catalysts are categorized according to structural features, clarifying common material systems across different fields. The factors influencing EPSF catalytic performance are subsequently outlined, followed by an evaluation of corresponding enhancement strategies. Finally, design strategies for EPSF catalysts across applications are analyzed, emphasizing the commonalities and distinctions in catalyst design for different fields. Insights are provided to inform future catalyst development.

Transformable Tumor Microenvironment-Responsive Oxygen Vacancy-Rich MnO2@Hydroxyapatite Nanospheres for Highly Efficient Cancer Sonodynamic Immunotherapy

Despite the promise of sonodynamic therapy (SDT)-mediated immunotherapy, the anticancer efficacy of current sonosensitizers is greatly limited by the immunosuppressive tumor microenvironment (TME) and their inability to selectively respond to it. Herein, oxygen vacancy-rich MnO2@hydroxyapatite (Ca10(PO4)6(OH)2) core-shell nanospheres (denoted as Ov-MO@CPO) as an advanced TME-responsive sonosensitizer for sonodynamic immunotherapy is demonstrated. The Ov-MO@CPO maintains its structural integrity under neutral conditions but dissolves the pH-sensitive hydroxyapatite shell under acidic TME to release active oxygen vacancy-rich MnO2 core, which reinvigorates H2O2 consumption and hypoxia alleviation due to its catalase-like activity. Furthermore, the introduced oxygen vacancies optimize the electronic structure of Ov-MO@CPO, with active electronic states near the Fermi level and higher d-band center. It results in accelerated electron-hole pair separation and lower catalytic energy barriers to boost ultrasound (US)-initiated ROS production. These multimodal synergistic effects effectively reverse the immunosuppressive tumor microenvironment, inhibiting tumor growth and metastasis in 4T1 tumor-bearing mice. No evident toxic effects are observed in normal mouse tissues. Additionally, when combined with an immune checkpoint inhibitor, Ov-MO@CPO-mediated SDT further improves the effectiveness of immunotherapy. This work affords a new avenue for developing TME-dependent sonosensitizers for SDT-mediated immunotherapy.

Construction of a hydrogen-bonded organic framework-based therapeutic platform by one-pot method

The anticancer drug camptothecin (CPT) was successfully in situ loaded into a hydrogen-bonded organic framework (HOF) by one-pot method with a high loading efficiency of 42 wt%. The resultant HOF based therapeutic platform could suppress the tumor growth effectively.

A HOF-101@AgNPs-based dual-signal mode aptasensor for electrochemiluminescence and fluorescence detection of E. coli O157:H7

Escherichia coli O157:H7 (E. coli O157:H7) emerges as a foodborne pathogen, emphasizing the imperative for creating precise detection tools. An ultrasensitive electrochemiluminescence/fluorescence (ECL/FL) dual-signal mode aptasensor was constructed for the detection of E. coli O157:H7. Ultrafine silver nanoparticles were loaded on the surface of hydrogen-bonded organic skeleton materials by in-situ photoreduction method, and then combined with aptamers that can identify specific targets to prepare HOF-101@AgNPs@Apt, greatly simplifying the ECL/FL dual-signal mode probe fabrication process and improving sensing reliability. HOF-101@AgNPs@Apt had both strong ECL luminescence and fluorescence, resulting in a high detection sensitivity. The low limit of detection (LOD) for ECL and FL were 0.48 CFU mL-1 and 2.39 CFU mL-1, respectively. Moreover, the proposed dual-signal mode aptasensor has been successfully applied to determine E. coli O157:H7 levels in tap water and milk with superior accuracy and high antiinterference capability, providing a promising method for food safety monitoring.

Engineering Sonosensitizer-Derived Nanotheranostics for Augmented Sonodynamic Therapy

Sonodynamic therapy (SDT), featuring noninvasive, deeper penetration, low cost, and repeatability, is a promising therapy approach for deep-seated tumors. However, the general or only utilization of SDT shows low efficiency and unsatisfactory treatment outcomes due to the complicated tumor microenvironment (TME) and SDT process. To circumvent the issues, three feasible approaches for enhancing SDT-based therapeutic effects, including sonosensitizer optimization, strategies for conquering hypoxia TME, and combinational therapy are summarized, with a particular focus on the combination therapy of SDT with other therapy modalities, including chemodynamic therapy, photodynamic therapy, photothermal therapy, chemotherapy, starvation therapy, gas therapy, and immunotherapy. In the end, the current challenges in SDT-based therapy on tumors are discussed and feasible approaches for enhanced therapeutic effects are provided. It is envisioned that this review will provide new insight into the strategic design of high-efficiency sonosensitizer-derived nanotheranostics, thereby augmenting SDT and accelerating the potential clinical transformation.

Focused starvation of tumor cells using glucose oxidase: A comprehensive review

Starvation therapy targets the high metabolic demand of tumor cells. It primarily leans over the consumption of intracellular glucose and simultaneous blockade of alternative metabolic pathways. The strategy involves the use of glucose oxidase (GOx) for catalyzing the conversion of glucose into gluconic acid and hydrogen peroxide. Under these conditions, metabolic re-programming of tumor cells enables the utilization of substrates such as amino acids, fatty acids and lipids. This can be overcome by co-administration of chemo-, photo- and immuno-therapeutics together with glucose oxidase. Targeted delivery of glucose oxidase at tumor site can be enabled with the use of nanoformulations. In this review, we highlight that the outcomes of starvation therapy can be improved using rationally developed nano-formulations. It is possible to load synergistically acting bioactives in these formulations and deliver in site-specific manner and hence achieve the elimination of tumors cells with greater efficacy.

A triple-mode strategy combining low-temperature photothermal, photodynamic, and chemodynamic therapies for treating infectious skin wounds

The skin is the first natural barrier of the human body. Bacterial infections severely hinder the healing process of skin wounds and pose a great threat to human health. Therefore, it is particularly urgent to develop new antimicrobial strategies for bacterial pathogen clearance and wound healing. In this study, a metal-organic framework (MOF), Fe-MIL88B-NH2, was incorporated with the photosensitizer indocyanine green (ICG) to construct composite nanoparticles (MOF@ICG NPs) with multiple antibacterial activities. Under mild near-infrared (NIR) irradiation, the photosensitizer ICG in the MOF@ICG NPs undergoes photothermal conversion (∼45 °C) and photodynamic reactions to generate heat and singlet oxygen (1O2). In addition, the Fenton reaction of the NPs with hydrogen peroxide (H2O2) in the bacterial infection microenvironment resulted in the generation of hydroxyl radicals (˙OH), thus achieving the three-mode combination of low-temperature photothermal therapy (PTT)/photodynamic therapy (PDT)/chemodynamic therapy (CDT). The in vitro experimental results showed that MOF@ICG MPs had excellent antibacterial properties and good cytocompatibility, with some ability to promote the migration of L-929 fibroblasts. Furthermore, under NIR irradiation, MOF@ICG NPs could significantly kill bacteria and promote skin wound healing according to the results of animal experiments. The wound healing rate reached 87.1% after 7 days of treatment. The research results break through the limitations of single-mode antibacterial technology and provide certain theoretical guidance and technical support for the research and development of new antibacterial materials.

Catalytic Nanoparticles in Biomedical Applications: Exploiting Advanced Nanozymes for Therapeutics and Diagnostics

Catalytic nanoparticles (CNPs) as heterogeneous catalyst reveals superior activity due to their physio-chemical features, such as high surface-to-volume ratio and unique optical, electric, and magnetic properties. The CNPs, based on their physio-chemical nature, can either increase the reactive oxygen species (ROS) level for tumor and antibacterial therapy or eliminate the ROS for cytoprotection, anti-inflammation, and anti-aging. In addition, the catalytic activity of nanozymes can specifically trigger a specific reaction accompanied by the optical feature change, presenting the feasibility of biosensor and bioimaging applications. Undoubtedly, CNPs play a pivotal role in pushing the evolution of technologies in medical and clinical fields, and advanced strategies and nanomaterials rely on the input of chemical experts to develop. Herein, a systematic and comprehensive review of the challenges and recent development of CNPs for biomedical applications is presented from the viewpoint of advanced nanomaterial with unique catalytic activity and additional functions. Furthermore, the biosafety issue of applying biodegradable and non-biodegradable nanozymes and future perspectives are critically discussed to guide a promising direction in developing span-new nanozymes and more intelligent strategies for overcoming the current clinical limitations.

A cancer-targeted glutathione-gated probe for self-sufficient ST/CDT combination therapy and FRET-based miRNA imaging

A cancer-targeted glutathione (GSH)-gated theranostic probe (CGT probe) for intracellular miRNA imaging and combined treatment of self-sufficient starvation therapy (ST) and chemodynamic therapy (CDT) was developed. The CGT probe is constructed using MnO2 nanosheet (MS) as carrier material to adsorb the elaborately designed functional DNAs. It can be internalized by cancer cells via specific recognition between the AS1411 aptamer and nucleolin. After CGT probe entering the cancer cells, the overexpressed GSH, as gate-control, can degrade MS to Mn2+ which can be used for CDT by Fenton-like reaction. Simultaneously, Mn2+-mediated CDT can further cascade with the enzyme-like activities (catalase-like activity and glucose oxidase-like activity) of CGT probe, achieving self-sufficient ST/CDT synergistic therapy. Meanwhile, the anchored DNAs are released, achieving in situ signal amplification via disubstituted-catalytic hairpin assembly (DCHA) and FRET (fluorescence resonance energy transfer) imaging of miR-21. The in vitro and in vivo experiments demonstrated that accurate and sensitive miRNA detection can be achieved using the CGT probe. Overall, the ingenious CGT probe opens a new avenue for the development of early clinical diagnosis and cancer therapy.

Metal-organic frameworks as candidates for tumor sonodynamic therapy: Designable structures for targeted multifunctional transformation

Sonodynamic therapy (SDT), utilizing ultrasound (US) as the trigger, has gained popularity recently as a therapeutic approach with significant potential for treating various diseases. Metal-organic frameworks (MOFs), characterized by structural flexibility, are prominently emerging in the SDT realm as an innovative type of sonosensitizer, offering functional tunability and biocompatibility. However, due to the inherent limitations of MOFs, such as low reactivity to reactive oxygen species and challenges posed by the complex tumor microenvironment, MOF-based sonosensitizers with singular functions are unable to demonstrate the desired therapeutic efficacy and may pose risks of toxicity, limiting their biological applications to superficial tissues. MOFs generally possess distinctive crystalline structures and properties, and their controlled coordination environments provide a flexible platform for exploring structure-effect relationships and guiding the design and development of MOF-based nanomaterials to unlock their broader potential in biological fields. The primary focus of this paper is to summarize cases involving the modification of different MOF materials and the innovative strategies developed for various complex conditions. The paper outlines the diverse application areas of functionalized MOF-based sonosensitizers in tumor synergistic therapies, highlighting the extensive prospects of SDT. Additionally, challenges confronting SDT are briefly summarized to stimulate increased scientific interest in the practical application of MOFs and the successful clinical translation of SDT. Through these discussions, we strive to foster advancements that lead to early-stage clinical benefits for patients. STATEMENT OF SIGNIFICANCE: 1. An overview for the progresses in SDT explored from a novel and fundamental perspective. 2. Different modification strategies to improve the MOFs-mediated SDT efficacy are provided. 3. Guidelines for the design of multifunctional MOFs-based sonosensitizers are offered. 4. Powerful tumor ablation potential is reflected in SDT-led synergistic therapies. 5. Future challenges in the field of MOFs-based SDT in clinical translation are suggested.

Nanomedicine/materdicine-enabled sonocatalytic therapy

The advent of numerous treatment modalities with desirable therapeutic efficacy has been made possible by the fast development of nanomedicine and materdicine, among which the ultrasound (US)-triggered sonocatalytic process as minimal or non-invasive method has been frequently employed for diagnostic and therapeutic purposes. In comparison to phototherapeutic approaches with inherent penetration depth limitations, sonocatalytic therapy shatters the depth limit of photoactivation and offers numerous remarkable prospects and advantages, including mitigated side effects and appropriate tissue-penetration depth. Nevertheless, the optimization of sonosensitizers and therapies remains a significant issue in terms of precision, intelligence and efficiency. In light of the fact that nanomedicine and materdicine can effectively enhance the theranostic efficiency, we herein aim to furnish a cutting-edge review on the latest progress and development of nanomedicine/materdicine-enabled sonocatalytic therapy. The design methodologies and biological features of nanomedicine/materdicine-based sonosensitizers are initially introduced to reveal the underlying relationship between composition/structure, sonocatalytic function and biological effect, in accompany with a thorough discussion of nanomedicine/materdicine-enabled synergistic therapy. Ultimately, the facing challenges and future perspectives of this intriguing sonocatalytic therapy are highlighted and outlined to promote technological advancements and clinical translation in efficient disease treatment.

Ultrasound activated probe for disease imaging and therapy In-Vivo

Sonodynamic therapy (SDT) is the use of ultrasound (US) to excite sonosensitizers to produce reactive oxygen species (ROS) to induce tumor cell death, thereby achieving therapeutic purposes. Based on the strong tissue penetration ability of ultrasound, SDT can realize the treatment of deeper tumors, and it is targeted, can be specifically concentrated at the tumor site, and has little impact on surrounding normal tissues. It has broad clinical transformation prospects. Therefore, sonosensitizers are the key to SDT, and the exploration of sonosensitizers with excellent therapeutic performance has received great attention. We reviewed the development of ultrasound-inspired sound sensitizers for imaging and treatment. First, different types of sonosensitizers are introduced, the construction and performance of inorganic, organic and hybrid types of sonosensitizers are evaluated, followed by a review of different image-guided SDT, and finally the key problems and solutions in this field are discussed in detail.

Enhanced photodynamic therapy through multienzyme-like MOF for cancer treatment

Overcoming resistance to apoptosis is a major challenge in cancer therapy. Recent research has shown that manipulating mitochondria, the organelles critical for energy metabolism in tumor cells, can increase the effectiveness of photodynamic therapy and trigger apoptosis in tumor cells. However, there is currently insufficient research and effective methods to exploit mitochondrial damage to induce apoptosis in tumor cells and improve the effectiveness of photodynamic therapy. In this study, we present a novel nanomedicine delivery and therapeutic system called PyroFPSH, which utilizes a nanozymes-modified metal-organic framework as a carrier. PyroFPSH exhibits remarkable multienzyme-like activities, including glutathione peroxidase (GPx) and catalase (CAT) mimicry, allowing it to overcome apoptosis resistance, reduce endogenous glutathione levels, and continuously generate reactive oxygen species (ROS). In addition, PyroFPSH can serve as a carrier for the targeted delivery of sulfasalazine, a drug that can induce mitochondrial depolarization in tumor cells, thereby reducing oxygen consumption and energy supply in the mitochondria of tumor cells and weakening resistance to other synergistic treatment approaches. Our experimental results highlight the potential of PyroFPSH as a versatile nanoplatform in cancer treatment. This study expands the biomedical applications of nanomaterials as platforms and enables the integration of various novel therapeutic strategies to synergistically improve tumor therapy. It deepens our understanding of multienzyme-mimicking active nanocarriers and mitochondrial damage through photodynamic therapy. Future research can further explore the potential of PyroFPSH in clinical cancer treatment and improve its drug loading capacity, biocompatibility and targeting specificity. In summary, PyroFPSH represents a promising therapeutic approach that can provide new insights and possibilities for cancer treatment.

Cascade strategy for glucose oxidase-based synergistic cancer therapy using nanomaterials

Nanomaterial-based cancer therapy faces significant limitations due to the complex nature of the tumor microenvironment (TME). Starvation therapy is an emerging therapeutic approach that targets tumor cell metabolism using glucose oxidase (GOx). Importantly, it can provide a material or environmental foundation for other diverse therapeutic methods by manipulating the properties of the TME, such as acidity, hydrogen peroxide (H2O2) levels, and hypoxia degree. In recent years, this cascade strategy has been extensively applied in nanoplatforms for ongoing synergetic therapy and still holds undeniable potential. However, only a few review articles comprehensively elucidate the rational designs of nanoplatforms for synergetic therapeutic regimens revolving around the conception of the cascade strategy. Therefore, this review focuses on innovative cascade strategies for GOx-based synergetic therapy from representative paradigms to state-of-the-art reports to provide an instructive, comprehensive, and insightful reference for readers. Thereafter, we discuss the remaining challenges and offer a critical perspective on the further advancement of GOx-facilitated cancer treatment toward clinical translation.

Recent advances in glucose oxidase-based nanocarriers for tumor targeting therapy

Glucose oxidase (GOx) can specifically catalyze the conversion of β-d-glucose into gluconic acid and hydrogen peroxide (H2O2) in the presence of oxygen, making it promising for tumor starvation therapy and oxidative therapy. However, GOx's immunogenicity, poor in vivo stability, short half-life, and potential systemic toxicity, limit its application in cancer therapy. Nanocarriers are capable of improving the pharmacological properties of therapeutic drugs (e.g. stability, circulating half-life, and tumor accumulation) and lower toxicity, hence resolving GOx issues and enhancing its efficacy. Although the application of targeted nanocarriers based on GOx has recently flourished, this field has not yet been reviewed and evaluated. Herein, we initially examined the mechanism of GOx-based nanocarriers for enhanced tumor therapy. Also, we present a comprehensive and up-to-date review that highlights GOx-based nanocarriers for tumor targeting therapy. This review expands on GOx-based nano-targeted combination therapies from both passive and active targeting perspectives, meanwhile, active targeting is further classified into ligand-mediated targeting and physical-mediated targeting. Furthermore, this review also emphasizes the present challenges and promising advancements.

A Novel Platform of MOF for Sonodynamic Therapy Advanced Therapies

Metal-organic frameworks (MOFs) combined with sonodynamic therapy (SDT) have been introduced as a new and efficient treatment method. The critical advantage of SDT is its ability to penetrate deep tissues and concentrate energy on the tumor site to achieve a non-invasive or minimally invasive effect. Using a sonosensitizer to generate reactive oxygen species (ROS) under ultrasound is the primary SDT-related method of killing tumor cells. In the presence of a sonosensitizer, SDT exhibits a more lethal effect on tumors. The fast development of micro/nanotechnology has effectively improved the efficiency of SDT, and MOFs have been broadly evaluated in SDT due to their easy synthesis, easy surface functionalization, high porosity, and high biocompatibility. This article reviews the main mechanism of action of sonodynamic therapy in cancer treatment, and also reviews the applications of MOFs in recent years. The application of MOFs in sonodynamic therapy can effectively improve the targeting ability of SDT and the conversion ability of reactive oxygen species, thus improving their killing ability on cancer cells. This provides new ideas for the application of micro/nano particles in SDT and cancer therapy.

Fe-Based Metal Organic Frameworks (Fe-MOFs) for Bio-Related Applications

Metal-organic frameworks (MOFs) are porous materials composed of metal ions and organic ligands. Due to their large surface area, easy modification, and good biocompatibility, MOFs are often used in bio-related fields. Fe-based metal-organic frameworks (Fe-MOFs), as important types of MOF, are favored by biomedical researchers for their advantages, such as low toxicity, good stability, high drug-loading capacity, and flexible structure. Fe-MOFs are diverse and widely used. Many new Fe-MOFs have appeared in recent years, with new modification methods and innovative design ideas, leading to the transformation of Fe-MOFs from single-mode therapy to multi-mode therapy. In this paper, the therapeutic principles, classification, characteristics, preparation methods, surface modification, and applications of Fe-MOFs in recent years are reviewed to understand the development trends and existing problems in Fe-MOFs, with the view to provide new ideas and directions for future research.

Recent advances in nanoscale metal-organic frameworks for cancer chemodynamic therapy

Chemodynamic therapy (CDT), a novel therapeutic approach based on Fenton (Fenton-like) reaction, has been widely employed for tumor therapy. This approach utilizes Fe, Cu, or other metal ions (Mn, Zn, Co, or Mo) to react with the excess hydrogen peroxide (H₂O₂) in tumor microenvironments (TME), and form highly cytotoxic hydroxyl radical (˙OH) to kill cancer cells. Recently, nanoscale metal-organic frameworks (nMOFs) have attracted considerable attention as promising CDT agents with the rapid development of cancer CDT. This review focuses on summarizing the latest advances (2020-2022) on the design of nMOFs as nanomedicine for CDT or combination therapy of CDT and other therapies. The future development and challenges of CDT are also proposed based on recent progress. Our group hopes that this review will enlighten the research and development of nMOFs for CDT.

Hybridization-driven fluorometric platform based on metal-organic frameworks for the identification of the highly homologous viruses

A novel fluorometric strategy for the simultaneous identification of SARS-CoV-2 and SARS-CoV was successfully established based on a hybridization-induced signal on-off-on mechanism. Here, one part of the probe (P1) of SARS-CoV-2 (P = P1/P2) is partially related to SARS-CoV, while the other part (P2) is completely irrelevant to SARS-CoV. They as smart gatekeepers were anchored on NH₂-MIL-88(Fe) (MOF@P1/P2) to turn off its catalytic performance. Only the specific SARS-CoV-2 genetic target can strongly restore the peroxidase-like activity of MOF@P1/P2. In the presence of o-phenylenediamine, SARS-CoV-2 can be efficiently detected with high sensitivity, accuracy, and reliability. This strategy demonstrated excellent analytical characteristics with a linear range (10^-9 M ∼ 10^-6 M) under the limit of detection of 0.11 nM not only in buffer but also in 10 % serum, which partly shows its practicability. Most importantly, with the help of the auxiliary test of MOF@P1 and MOF@P2, SARS-CoV-2 and SARS-CoV can be efficiently quantified and distinguished. This novel strategy has provided a breakthrough in the development of such identification. In the whole process, only a simple one-step experiment was involved. This circumvents the trouble of pretreatment experiments in traditional methods, including complex enzymatic mixtures, specialized experimental equipment, many primers optimization as well as reverse transcriptase. Additionally, this novel strategy is rapid, low-cost, and easy-to-use tools.

Multifunctional nanoparticle for cancer therapy

Cancer is a complex disease associated with a combination of abnormal physiological process and exhibiting dysfunctions in multiple systems. To provide effective treatment and diagnosis for cancer, current treatment strategies simultaneously focus on various tumor targets. Based on the rapid development of nanotechnology, nanocarriers have been shown to exhibit excellent potential for cancer therapy. Compared with nanoparticles with single functions, multifunctional nanoparticles are believed to be more aggressive and potent in the context of tumor targeting. However, the development of multifunctional nanoparticles is not simply an upgraded version of the original function, but involves a sophisticated system with a proper backbone, optimized modification sites, simple preparation method, and efficient function integration. Despite this, many well-designed multifunctional nanoparticles with promising therapeutic potential have emerged recently. Here, to give a detailed understanding and analyzation of the currently developed multifunctional nanoparticles, their platform structures with organic or inorganic backbones were systemically generalized. We emphasized on the functionalization and modification strategies, which provide additional functions to the nanoparticle. We also discussed the application combination strategies that were involved in the development of nanoformulations with functional crosstalk. This review thus provides an overview of the construction strategies and application advances of multifunctional nanoparticles.

Confining enzymes in porous organic frameworks: from synthetic strategy and characterization to healthcare applications

Enzymes are a class of natural catalysts with high efficiency, specificity, and selectivity unmatched by their synthetic counterparts and dictate a myriad of reactions that constitute various cascades in living cells. The development of suitable supports is significant for the immobilization of structurally flexible enzymes, enabling biomimetic transformation in the extracellular environment. Accordingly, porous organic frameworks, including metal organic frameworks (MOFs), covalent organic frameworks (COFs) and hydrogen-bonded organic frameworks (HOFs), have emerged as ideal supports for the immobilization of enzymes because of their structural features including ultrahigh surface area, tailorable porosity, and versatile framework compositions. Specially, organic framework-encased enzymes have shown significant enhancement in stability and reusability, and their tailorable pore opening provides a gatekeeper-like effect for guest sieving, which is beneficial for mimicking intracellular biocatalysis processes. This immobilization technique brings new insight into the development of next-generation enzyme materials and shows huge potential in healthcare applications, such as biomarker diagnosis, biostorage, and cancer and antibacterial therapies. In this review, we describe the state-of-the-art strategies for the structural immobilization of enzymes using the well-explored MOFs and burgeoning COFs and HOFs as scaffolds, with special emphasis on how these porous framework-confined technologies can provide a favorable microenvironment for mimicking natural biocatalysis. Subsequently, advanced characterization techniques for enzyme conformation, the effect of the confined microenvironment on the activity of enzymes, and the emerging healthcare applications will be surveyed.

Glucose Metabolism Intervention-Facilitated Nanomedicine Therapy

Ordinarily, cancer cells possess features of abnormally increased nutrient intake and metabolic pathways. The disorder of glucose metabolism is the most important among them. Therefore, starvation therapy targeting glucose metabolism specifically, which results in metabolic disorders, restricted synthesis, and inhibition of tumor growth, has been developed for cancer therapy. However, issues such as inadequate targeting effectiveness and drug tolerance impede their clinical transformation. In recent years, nanomaterial-assisted starvation treatment has made significant progress in addressing these challenges, whether as a monotherapy or in combination with other medications. Herein, representative researches on the construction of nanosystems conducting starvation therapy are introduced. Elaborate designs and interactions between different treatment mechanisms are meticulously mentioned. Not only are traditional treatments based on glucose oxidase involved, but also newly sprung small molecule agents targeting glucose metabolism. The obstacles and potential for advancing these anticancer therapies were also highlighted in this review.

Research Progress on Improving the Efficiency of CDT by Exacerbating Tumor Acidification

In recent years, chemodynamic therapy (CDT) has received extensive attention as a novel means of cancer treatment. The CDT agents can exert Fenton and Fenton-like reactions in the acidic tumor microenvironment (TME), converting hydrogen peroxide (H₂O₂) into highly toxic hydroxyl radicals (·OH). However, the pH of TME, as an essential factor in the Fenton reaction, does not catalyze the reaction effectively, hindering its efficiency, which poses a significant challenge for the future clinical application of CDT. Therefore, this paper reviews various strategies to enhance the antitumor properties of nanomaterials by modulating tumor acidity. Ultimately, the performance of CDT can be further improved by inducing strong oxidative stress to produce sufficient ·OH. In this paper, the various acidification pathways and proton pumps with potential acidification functions are mainly discussed, such as catalytic enzymes, exogenous acids, CAIX, MCT, NHE, NBCn1, etc. The problems, opportunities, and challenges of CDT in the cancer field are also discussed, thereby providing new insights for the design of nanomaterials and laying the foundation for their future clinical applications.

Recent Trends in Composite Nanozymes and Their Pro-Oxidative Role in Therapeutics

Nanozymes are inorganic nanostructures whose enzyme mimic activities are increasingly explored in disease treatment, taking inspiration from natural enzymes. The catalytic ability of nanozymes to generate reactive oxygen species can be used for designing effective antimicrobials and antitumor therapeutics. In this context, composite nanozymes are advantageous, particularly because they integrate the properties of various nanomaterials to offer a single multifunctional platform combining photodynamic therapy (PDT), photothermal therapy (PTT), and chemodynamic therapy (CDT). Hence, recent years have witnessed great progress in engineering composite nanozymes for enhanced pro-oxidative activity that can be utilized in therapeutics. Therefore, the present review traverses over the newer strategies to design composite nanozymes as pro-oxidative therapeutics. It provides recent trends in the use of composite nanozymes as antibacterial, antibiofilm, and antitumor agents. This review also analyzes various challenges yet to be overcome by pro-oxidative composite nanozymes before being used in the field.

Designing Triangular Silver Nanoplates with GSH/GSSG Surface Mixed States as Novel Nanoparticle-based Redox Mediators for Electrochemical Biosensing

Herein, a dual signal-quenched electrochemical (EC) biosensing strategy utilizing surface-engineered trisodium citrate (TSC)-glutathione (GSH)/oxidized glutathione (GSSG)-capped triangular silver nanoplates (Tri-Ag NPs_TSC-GSH/GSSG) as a novel nanoparticle-based redox mediator was explored for biomarker determination. In contrast with conventional redox mediators, Tri-Ag NPs_TSC-GSH/GSSG provided more admirable EC performance along with a lower oxidation potential (∼0.14 V). Taking advantage of the split-type mode, the immune response in a 96-well microplate was independent from EC detection, which could effectively eliminate the biological interference and thereby greatly enhance the sensitivity. As for the surface engineering process of Tri-Ag NPs, it was composed of partial GSH replacement and the formation of the GSH/GSSG surface mixed state. Primarily, the signal response of Ag NPs_TSC-GSH decreased due to the hindrance of GSH on electron transfer. Moreover, varying proportions of GSH/GSSG could further impede the oxidation process of Tri-Ag NPs_TSC-GSH/GSSG and eventually realize efficient dual signal quenching of this system. Notably, the ZIF-67@MIL-88B-GO_x nanocomposite as the label was applied for a cascade reaction system with GSH peroxidase-like activities to form the optimal GSH/GSSG proportion, causing sensitive changes in signal response with a range of different antigen concentrations. On this basis, the fabricated biosensor provided measurable outputs of aflatoxin B1 concentrations in a linear range of 0.0005-50 ng/mL with a low detection limit of 0.61 pg/mL (S/N = 3). All of the results indicated that the novel biosensor could be a promising analytical tool for future biomarker detection.

A Multifunctional Nanoplatform Based on Fenton-like and Russell Reactions of Cu, Mn Bimetallic Ions Synergistically Enhanced ROS Stress for Improved Chemodynamic Therapy

Chemodynamic therapy (CDT) based intracellular chemical reactions to produce highly cytotoxic reactive oxygen species has received wide attention. However, low efficiency of single CDT in weakly acidic pH and glutathione (GSH) overexpressed tumor cells has limited its clinical application. For this study were prepared two-dimensional metal-organic framework (MOF) to improve CDT efficiency based on the combined action of bimetallic CDT, consumption of overexpressed glutathione (GSH) in cells, folic acid (FA) induced tumor targeting and triphenylphosphine (TPP) induced mitochondrial targeting. With the use of Cu(II) as the central ion and tetrakis(4-carboxyphenyl)porphyrin (TCPP) as the ligand, two-dimensional Cu-MOF nanosheets were prepared, which were surface modified by manganese dioxide based on the in situ redox reaction between poly(allylamine hydrochloride) (PAH) and KMnO₄ to obtain Cu-MOF@MnO₂. Then FA and TPP were coupled with the nanosheets to form the title nanoplatform. Comprehensive physiochemical research has suggested that Cu(II) and MnO₂ constituents in the nanoplatform could consume intracellular GSH and hydrogen peroxide to generate hydroxyl radicals through a Fenton-like reaction; meanwhile Cu(II) could undergo a Russell reaction to produce cytotoxic singlet oxygen. Detailed in vitro and in vivo biological experiments have revealed a good biosafety profile and a high tumor suppression effect. Therefore, the present research has realized multiple and efficient CDT effects with the aid of the sequential targeting of FA/TPP, also providing a strategy for the development of CDT drugs based on polymetallic organic frameworks.

Bioenzyme-based nanomedicines for enhanced cancer therapy

Bioenzymes that catalyze reactions within living systems show a great promise for cancer therapy, particularly when they are integrated with nanoparticles to improve their accumulation into tumor sites. Nanomedicines can deliver toxic bioenzymes into cancer cells to directly cause their death for cancer treatment. By modulating the tumor microenvironment, such as pH, glucose concentration, hypoxia, redox levels and heat shock protein expression, bioenzyme-based nanomedicines play crucial roles in improving the therapeutic efficacy of treatments. Moreover, bioenzyme-mediated degradation of the major components in tumor extracellular matrix greatly increases the penetration and retention of nanoparticles in deep tumors and infiltration of immune cells into tumor tissues, thus enhancing the efficacies of chemotherapy, phototherapy and immunotherapy. In this review, we summarize the recent progresses of bioenzyme-based nanomedicines for enhanced cancer therapy. The design and working mechanisms of the bioenzyme-based nanomedicines to achieve enhanced chemotherapy, photothermal therapy, photodynamic therapy, chemodynamic therapy, radiotherapy and immunotherapy are introduced in detail. At the end of this review, a conclusion and current challenges and perspectives in this field are given.

Chemodynamic Therapy via Fenton and Fenton-Like Nanomaterials: Strategies and Recent Advances

Chemodynamic therapy (CDT), a novel cancer therapeutic strategy defined as the treatment using Fenton or Fenton-like reaction to produce •OH in the tumor region, was first proposed by Bu, Shi, and co-workers in 2016. Recently, with the rapid development of Fenton and Fenton-like nanomaterials, CDT has attracted tremendous attention because of its unique advantages: 1) It is tumor-selective with low side effects; 2) the CDT process does not depend on external field stimulation; 3) it can modulate the hypoxic and immunosuppressive tumor microenvironment; 4) the treatment cost of CDT is low. In addition to the Fe-involved CDT strategies, the Fenton-like reaction-mediated CDT strategies have also been proposed, which are based on many other metal elements including copper, manganese, cobalt, titanium, vanadium, palladium, silver, molybdenum, ruthenium, tungsten, cerium, and zinc. Moreover, CDT has been combined with other therapies like chemotherapy, radiotherapy, phototherapy, sonodynamic therapy, and immunotherapy for achieving enhanced anticancer effects. Besides, there have also been studies that extend the application of CDT to the antibacterial field. This review introduces the latest advancements in the nanomaterials-involved CDT from 2018 to the present and proposes the current limitations as well as future research directions in the related field.

Facile Synthesis of a Cubic Porphyrin-Based Covalent Organic Framework for Combined Breast Cancer Therapy

A cubic porphyrin-based covalent organic framework (COF) named CTP with excellent hydrophilicity was prepared with a facile method for the first time. Different from the conventional methods for the synthesis of porphyrin-based COFs, this facile strategy has greatly shortened the reaction time under mild conditions. Linking the porphyrin monomer into the COF overcame its poor solubility and biocompatibility and also narrowed the band gap owing to the formation of the π-conjugation structure. The improved biocompatibility and narrowed band gap enabled CTP to be an excellent sonosensitizer with an enhanced sonodynamic effect. Moreover, CTP could also effectively realize photothermal conversion under external irradiation due to the extended conjugated structure. This work developed a novel synthesis method for COFs and employed a COF as a sonosensitizer for the first time, which not only provided a new strategy to improve the efficiency of organic sonosensitizers but also inspired us to design more functional COFs for versatile applications.

Multifunctional Composite Nanosystems for Precise/Enhanced Sonodynamic Oxidative Tumor Treatment

Ultrasound-activated therapies have been regarded as the efficient strategy for tumor treatment, among which sonosensitizer-enabled sonodynamic oxidative tumor therapy features intrinsic advantages as compared to other exogenous trigger-activated dynamic therapies. Nanomedicine-based nanosonosensitizer design has been extensively explored for improving the therapeutic efficacy of sonodynamic therapy (SDT) of tumor. This review focuses on solving two specific issues, i.e., precise and enhanced sonodynamic oxidative tumor treatment, by rationally designing and engineering multifunctional composite nanosonosensitizers. This multifunctional design can augment the therapeutic efficacy of SDT against tumor by either improving the production of reactive oxygen species or inducing the synergistic effect of SDT-based combinatorial therapies. Especially, this multifunctional design is also capable of endowing the nanosonosensitizer with bioimaging functionality, which can effectively guide and monitor the therapeutic procedure of the introduced sonodynamic oxidative tumor treatment. The design principles, underlying material chemistry for constructing multifunctional composite nanosonosensitizers, intrinsic synergistic mechanism, and bioimaging guided/monitored precise SDT are summarized and discussed in detail with the most representative paradigms. Finally, the existing critical issues, available challenges, and potential future developments of this research area are also discussed for promoting the further clinical translations of these multifunctional composite nanosonosensitizers in SDT-based tumor treatment.

Ferroptosis in cancer therapeutics: a materials chemistry perspective

Ferroptosis, distinct from apoptosis, is a regulated form of cell death caused by lipid peroxidation that has attracted extensive research interest since it was first defined in 2012. Over the past five years, an increasing number of studies have revealed the close relationship between ferroptosis and materials chemistry, in particular nanobiotechnology, and have concluded that nanotechnology-triggered ferroptosis is an efficient and promising antitumor strategy that provides an alternative therapeutic approach, especially for apoptosis-resistant tumors. In this review, we summarize recent advances in ferroptosis-induced tumor therapy at the intersection of materials chemistry, redox biology, and tumor biology. The biological features and molecular mechanisms of ferroptosis are first outlined, followed by a summary of the feasible strategies to induce ferroptosis using nanomaterials and the applications of ferroptosis in combined tumor therapy. Finally, the existing challenges and future development directions in this emerging field are discussed, with the aim of promoting the progress of ferroptosis-based oncotherapy in materials science and nanoscience and enriching the antitumor arsenal.

Self-Assembly of Multifunctional DNA Nanohydrogels with Tumor Microenvironment-Responsive Cascade Reactions for Cooperative Cancer Therapy

A DNA structure-based nanoreactor has emerged as a promising biomaterial for antitumor therapy with its intrinsic biodegradability, biocompatibility, and tunable multifunctionality. Herein, the intelligent DNA nanohydrogel was reported to target cancer cells, control the size, be pH-responsive, and be loaded with glucose oxidase (GOx). Two kinds of X-shaped DNA monomers and DNA linkers were assembled to form a DNA nanohydrogel by hybridization. GOx was successfully encapsulated in the DNA nanohydrogel. The DNA linker was designed with i-motif sequences and modified with ferrocene (Fc). The i-motif-like quadruplex structures were formed in acidic tumor microenvironments, resulting in the disassembly of the DNA nanohydrogel to release GOx. The GOx could oxidize the intratumoral glucose to produce gluconic acid and H₂O₂. The generated H₂O₂ was catalyzed by Fc to induce toxic hydroxyl radicals (^•OH), which could effectively kill cancer cells. Both the in vitro and the in vivo results demonstrated that the multifunctional DNA nanohydrogel had high-efficiency tumor suppression through combined chemodynamic and starvation cancer therapies.

Selenium Vacancy Engineering Using Bi2Se3 Nanodots for Boosting Highly Efficient Photonic Hyperthermia

Despite bismuth-based energy conversion nanomaterials having attracted extensive attention for nanomedicine, the nanomaterials suffer from major shortcomings including low tumor accumulation, long internal retention time, and undesirable photothermal conversion efficiency (PCE). To combat these challenges, bovine serum albumin and folic acid co-modified Bi2Se3 nanomedicine with rich selenium vacancies (abbreviated as VSe-BS) was fabricated for the second near-infrared (NIR-II) light-triggered photonic hyperthermia. More importantly, selenium vacancies on the crystal planes (0 1 5) and (0 1 11) of VSe-BS with similar formation energies could be distinctively observed via aberration-corrected scanning transmission electron microscopy images. The defect engineering endows VSe-BS with enhanced conductivity, making VSe-BS possess outstanding PCE (54.1%) in the NIR-II biowindow and desirable photoacoustic imaging performance. Tumor ablation studies indicate that VSe-BS possesses satisfactory therapeutic outcomes triggered by NIR-II light. These findings give rise to inspiration for further broadening the biological applications of defect engineering bismuth-based nanomaterials.

Conjugated Coordination Porphyrin-based Nanozymes for Photo-/Sono-Augmented Biocatalytic and Homologous Tumor Treatments

Porphyrin-based nanozymes (Porzymes) have shown promising application potential to fight against tumors using catalytically generated reactive oxygen species from the excessively produced H2O2 in the tumor microenvironment. However, the low coordination porphyrin (CP) loading ratio, difficult controllable nanostructure, low bioavailability, and low biocatalytic activities of current established Porzymes have severely limited their antitumor applications. Here, a novel malignant melanoma cell membrane-coated Pd-based CP nanoplatform (Trojan Porzymes) has been synthesized for biocatalytic and homologous tumor therapies. The Trojan Porzymes exhibit a high CP loading ratio, uniform nanoscale size, single-atom nanostructure, homologous targeted ability, and high-efficiency photo/sono-augmented biocatalytic activities. The enzyme-like biocatalytic experiments display that the Trojan Porzymes can generate abundant •OH via chemodynamic path and 1O2 via visible light or ultrasound excitation. Then we demonstrate that the Trojan Porzymes show homologous targeting ability to tumor cells and can achieve efficient accumulation and long-term retention in cancer tissues. Our in vivo data further disclose that the photo/sono-assisted chemodynamic therapies can significantly augment the treatment efficiency of malignant melanoma. We believe that our work will afford a new biocatalytic and homologous strategy for future clinical malignant melanoma treatments, which may inspire and guide more future studies to develop individualized biomedicine in precise tumor therapies.

Fabrication of Versatile Hollow Metal-Organic Framework Nanoplatforms for Folate-Targeted and Combined Cancer Imaging and Therapy

Metal-organic frameworks (MOFs) have received extensive attention in the field of biomedicine, particularly serving as multifunctional theranostic nanoplatforms by integrating chemodrugs, imaging agents, and targeting agents. Herein, we report a facile strategy for the fabrication of a hollow and monodisperse MOF (denoted hMIL-88B(Fe)@ZIF-8) consisting of ZIF-8 nanoparticles loaded on the external shell of hollow MIL-88B(Fe). In particular, the hybrid hollow MOF was constructed by partially etching spindlelike MIL-88B(Fe) nanoparticles with 2-methylimidazole in the presence of zinc ions. The obtained hMIL-88B(Fe)@ZIF-8 was then used as a drug/cargo delivery vehicle for loading doxorubicin (DOX), manganese oxide (MnO_x) nanoparticles, and folic acid (FA), forming a multifunctional nanoplatform (denoted hM@ZMDF). Importantly, the resulting hM@ZMDF exhibited a specific targeting property for the FA receptor-overexpressed cancer cells (MCF-7 and HepG-2 cells) and then it unloaded DOX and Fe³⁺ in the tumor microenvironment. Consequently, DOX played dual roles as a chemotherapeutic drug and a fluorescent imaging agent. Also, the released Fe³⁺ could mediate the Fenton reaction and intracellularly generate toxic hydroxyl radicals in the presence of high glutathione in cancer cells. In addition, MnO_x nanoparticles could participate in magnetic resonance imaging. Therefore, the versatile hM@ZMDF nanoplatforms have great potential for smart cancer therapy.

An MSN-based synergistic nanoplatform for root canal biofilm eradication via Fenton-enhanced sonodynamic therapy

The validity and biocompatibility of irrigating agents are imperative for the success of root canal therapy. The imperfections in the currently available irrigants highlight the fact that more advanced technologies and strategies are required for complete disinfection in endodontic treatments. In the present study, a Fenton reaction-enhanced antimicrobial sonodynamic therapy (SDT) platform was fabricated for root canal disinfection. Firstly, mesoporous silica nanoparticles (MSNs) were synthesized, grafted with an amino group and then conjugated with sonosensitizer protoporphyrin IX (PpIX). Iron ions were then anchored (M@P-Fe) to initiate a Fenton reaction. Nanoparticle characterization by size and zeta potential measurements, scanning electron microscopy, transmission electron microscopy and thermogravimetric analysis confirmed that the platform was successfully developed. Reactive oxygen species (ROS) generation assessment, methylene blue degradation and electron spin resonance assays illustrated upon ultrasound (US) irradiation, that augmented ROS, can be produced by US activated PpIX and iron mediated Fenton reactions from low concentration H2O2 (0.01%). In vitro anti-Enterococcus faecalis efficacy was demonstrated by growth curve and colony forming unit measurements. Confocal laser scanning microscopy and scanning electron microscopy observations illustrated the effectiveness of the platform on in situ biofilm eradication in root canal. Owing to the stronger oxidizing capability and short lifetime of ROS, the Fenton reaction-enhanced SDT can induce detrimental oxidative damage to bacteria upon activation of US while avoiding nonspecific toxicity to cells, which was verified by cytotoxicity evaluations using CCK-8 assay and morphology observation of MC3T3-E1 cells. Compared to commonly used NaClO, this nanoplatform displayed desirable anti-bacterial, anti-biofilm abilities and better biocompatibility. These results highlight that the integrated M@P-Fe + US + H2O2 platform is a promising candidate for US enhanced root canal irrigation and disinfection.