Metal-Organic Frameworks (MOF)-Assisted Sonodynamic Therapy in Anticancer Applications

A carrier-free ultrasound-responsive polyphenol nanonetworks with enhanced sonodynamic-immunotherapy for synergistic therapy of breast cancer

Sonodynamic therapy (SDT) is an efficient non-invasive strategy for treating breast cancer. However, the therapeutic efficacy of SDT is greatly limited by various defense mechanisms in the tumor microenvironment, particularly the overexpression of B-cell lymphoma-2 (Bcl-2). In this study, based on drug self-delivery systems, a carrier-free ultrasound-responsive polyphenol nanonetwork (GTC) was developed to enhance SDT by inhibiting Bcl-2. A one-pot method, involving the interaction of the polyphenolic Bcl-2 inhibitor gossypol (GOS), transferrin, and the sonosensitizer chlorin e6 (Ce6), was used to synthesize the GTC. The GTC was efficiently internalized by MDA-MB-231 and 4T1 cells through specific binding to transferrin receptors, and no external carriers were needed. After cellular internalization, GOS increased the lethality of Ce6-mediated SDT by reducing the expression of the Bcl-2 protein, which caused multiple toxic effects. RNA-seq analysis confirmed the transcriptomic alterations in oxidative stress and apoptotic pathways induced by the GTC nanosystem. In vivo studies revealed that GOS-assisted SDT not only eliminated tumors through sonodynamic effects and triggered immunogenic cell death but also enhanced sono-immunotherapy, thus effectively suppressing distant tumors and metastasis. This study might provide insights into carrier-free nanomedicines for SDT-based synergistic tumor therapy.

Current landscape of metal-organic framework-mediated nucleic acid delivery and therapeutics

Nucleic acid drugs utilize DNA or RNA molecules to modulate abnormal gene expression or protein translation in cells, enabling precise treatment for specific conditions. In recent years, nucleic acid drugs have demonstrated tremendous potential in vaccine development and treating genetic disorders. Currently, the primary carriers for clinically approved nucleic acid therapies include lipid nanoparticles and viral vectors. Beyond that, metal-organic frameworks (MOFs) are highly ordered, porous nanomaterials formed through the self-assembly of metal ions and organic ligands via coordination bonds. Their porosity structure offers great loading efficiency, stability, tunability, and biocompatibility, making them an attractive option for nucleic acid delivery. Given the research on MOFs as nucleic acid carriers has garnered significant attention in recent years, this review provides an overview of the therapeutic strategies and advancements in MOF-mediated nucleic acid delivery. The unique properties of various MOF carriers are introduced, and different approaches for nucleic acid loading are parallelly compared. Moreover, a systematic classification based on the type of nucleic acid cargo loaded in MOFs and corresponding applications is thoroughly described. This summary outlines the unique mechanisms through MOFs enhance nucleic acid delivery and emphasizes their substantial impact on therapeutic efficacy. In addition, the utilization of MOF-mediated nucleic acid treatment in combination with other therapies against malignant tumors is discussed in particular. Finally, an outlook on the challenges and potential opportunities of this technology in future translational production and clinical implementation is presented and explored.

Engineered Metal-Organic Framework with Stereotactic Anchoring and Spatial Separation of Porphyrins for Amplified Ultrasound-Mediated Pyroptosis and Cancer Immunotherapy

Ultrasound-mediated reactive oxygen species (ROS) generation is pivotal in specifically inducing pyroptosis of tumor cells. However, the effectiveness of pyroptosis is generally hindered by the constraints of ROS generation efficiency. Herein, a new porphyrin-based metal-organic framework (Fe(TCPP)-MOF) was rationally designed via an innovative dual-solvent strategy to amplify ROS generation for ultrasound-controlled pyroptosis. The crystal structure of Fe(TCPP)-MOF was elucidated by continuous rotation electron diffraction technique, revealing its regular and rigid conformation. The porphyrin molecules were precisely oriented and firmly confined within the scaffold, effectively restricting intramolecular motion. The ample distance of 6.8 Å between two porphyrin molecules, combined with the interaction region indicator visualization, confirmed the absence of π-π stacking interactions in the Fe(TCPP)-MOF framework, thereby avoiding the aggregation-caused quenching effect. Furthermore, the permanent porosity and expansive surface area of Fe(TCPP)-MOF enhanced its interaction with oxygen. These ingenious structural features endowed Fe(TCPP)-MOF with a unique ability to generate a large amount of singlet oxygen under ultrasound activation. Meanwhile, the impetus of ultrasound also accelerated the rate of the Fenton reaction catalyzed by iron ions, significantly boosting the generation of hydroxyl radicals. Benefiting from the dual amplification of ROS, Fe(TCPP)-MOF could efficiently induce tumor cells pyroptosis under ultrasound stimulation, thereby intensifying the potency of cancer immunotherapy.

Ultrasound-Controllable Release of Carbon Monoxide in Multifunctional Polymer Coating for Synergetic Treatment of Catheter-Related Infections

Medical catheters are susceptible to biological contamination and pathogen invasion, leading to infection and inflammatory complications. The development of antimicrobial coatings for medical devices has emerged as a promising strategy. However, limited biological functionality and the incompatibility between bactericidal properties and biosafety remain great challenges. Herein, a multifunctional polymer coating (CPB-Ac) is created, incorporating an ultrasonic-responsive carbon monoxide release unit (CORM-Ac) and antifouling unit to treat catheter-related complications. As-synthesized CPB-Ac polymer can be stably anchored to various medical devices with arbitrary shapes and compositions via facile UV treatment. Both in vivo and vitro experiments demonstrated that this multi-functional coating exhibits anti-fouling, anti-inflammatory, and broad-spectrum antibacterial activities as well as good biosafety. During the initial implantation phase, the antifouling units of CPB-Ac coating effectively inhibit the attachment of biological contaminants, significantly reducing the risk of thrombosis and bacterial infection. Once bacterial infection occurs, ultrasonic irradiation can activate CPB-Ac coating to release CO with a much higher amount of 55.3 µm than non-ultrasound controls, therefore rapidly eliminating bacteria and alleviating inflammatory response. It is believed that the work may provide an effective method for the development of next-generation intelligent medical coatings against catheter-related complications.

Recent advances in near-infrared organic photosensitizers for photodynamic cancer therapy

With the advancement of photodynamic therapy, various photosensitizers have been developed to enhance the efficacy of cancer treatment while minimizing side effects. Recently, near-infrared organic fluorophores have gained significant attention as promising photodynamic agents for cancer therapy due to their tunable photophysical properties, structural versatility, good biocompatibility, high biosafety, and synthetic flexibility. In particular, near-infrared organic photosensitizers offer several notable advantages, including deep tissue penetration, a low fluorescence background for bioimaging, and reduced damage to biological tissues compared to traditional visible-spectrum photosensitizers. In this minireview, we will discuss the current developments in near-infrared organic photosensitizers for photodynamic cancer therapy. Furthermore, we will briefly highlight the challenges and prospects in this field. This minireview aims to encourage more researchers to develop advanced near-infrared organic photosensitizers and facilitate their transition from laboratory research to preclinical studies and ultimately to clinical use.

Tunable Hierarchically Porous Gadolinium-Based Metal-Organic Frameworks for Bacteria-Targeting Magnetic Resonance Imaging and In Situ Anti-Bacterial Therapy

Currently, there are no non-invasive tools to accurately diagnose deep surgical site bacterial infections before they cause significant anatomical damage in the clinic. An urgent need exists for bacteria-targeting bifunctional probes for the detection of deep bacterial infections and precise in situ treatment. Herein, the bacteria-targeting 1-borono-3,5-benzenedicarboxylic acid (BBDC) ligand and paramagnetic Gd3 + into one single metal-organic frameworks (MOFs) are integrated, synergistically realizing bacteria-specific magnetic resonance imaging (MRI) diagnosis and MRI-guided antibacterial treatment. Molecular simulations and nitrogen adsorption-desorption experiments demonstrate that a hierarchical porous structure can be constructed by tuning the Gd3 + /BBDC ratio, which endows the Gd-BBDC1.25 MOFs with an impressive longitudinal proton relaxivity of 15.81 mM-1 s-1. In particular, the bacteria-targeting boronic acid group in BBDC remained intact during the MOF synthesis, ensuring that Gd-BBDC1.25 MOFs have a unique combination of high sensitivity and specificity for bacteria. Through an in situ reduction reaction, silver nanoparticles （Ag NPs）-modified Gd-BBDC1.25 MOFs to form Ag@Gd-BBDC1.25, an interfacial Schottky heterojunction nanozyme, which enhances their peroxidase (POD)-catalyze activity. Furthermore, it is demonstrated that the bacteria-targeting Ag@Gd-BBDC1.25 bifunctional probe can image as few as 105 colony-forming units (cfu) in vivo and effectively eradicate the bacteria in situ.

Renal-Clearable Metalloporphyrin Complex-Based Nanosonosensitizers Using Photoacoustic Imaging Guiding to Enhance Sonodynamic Cancer Therapy

Sonodynamic therapy (SDT) is a noninvasive approach to tumor treatment, with ongoing efforts being focused on developing highly effective sonosensitizers with low toxicity. Herein, a liquid-phase stripping technique was introduced as a simple reflux method for synthesizing ultrasmall Mn-PCN-224 nanodots (MM NDs). Compared with PCN-224 nanodots, the synthesized MM NDs, which function as renal-clearable nanoagents, produced 2.42 times more reactive oxygen species (ROS) under identical ultrasound (US) irradiation conditions. In vivo and in vitro experiments revealed that A549 lung cancer cells treated with MM NDs under US irradiation and H2O2 exhibited a relative cell viability of ∼9% and a tumor inhibition rate of ∼91%. This result demonstrates that MM NDs can efficiently increase the effectiveness of SDT by leveraging their catalase-like activity and ultrasmall size (4 nm) to prevent ROS quenching. Furthermore, these nanoagents could be effectively utilized for photoacoustic (PA) imaging to track their accumulation in tumors and monitor the alleviation of the hypoxic tumor microenvironment. Notably, MM ND-mediated SDT demonstrated superior penetration depth compared to PDT, making it more effective in inhibiting contralateral tumors while facilitating deep-tissue treatment. Thus, this study introduces renal-clearable nanoagents with promising potential for PA-guided SDT, thereby paving the way for more effective tumor treatment strategies.

UiO-66 MOFs-Based "Epi-Nano-Sonosensitizer" for Ultrasound-Driven Cascade Immunotherapy against B-Cell Lymphoma

B-cell lymphoma (BCL) is a hematological malignancy with high heterogeneity and represents an aggressive proliferation of mature B-cells. Despite the initial success of traditional treatments for BCL in clinical trials, a majority of patients eventually develop resistance to therapy and have poor clinical outcomes. Epigenetic dysregulation is a major contributor to the pathogenesis of BCL, and therapies targeting epigenetic pathways is a promising alternative strategy for treating BCL. Herein, we developed a metal-organic framework (MOF)-based nano-sonosensitizer for ultrasound-driven cascade immunotherapy against BCL. The nano-sonosensitizer was synthesized by encapsulating copper complex of the m6A-mRNA demethylase inhibitor into UiO-66-NH2, which possesses a Z-scheme heterostructure and allows efficient electron-hole pair separation for generating reactive oxygen species (ROS) under ultrasound activation. These CuR@UiO66 sonosensitizers were functionalized with mPEG-PO3 and anti-CD19 antibody, and the resulting CRUPPA19 particles could specifically accumulate in the BCL tissue and also target lymphoma cells that infiltrated into the bone marrow. Once internalized, CRUPPA19 could induce intracellular ROS production and apoptosis under ultrasound irradiation. Subsequently, ultrasonic stimulation triggered autophagy-mediated release of Cu and Rhein from CRUPPA19, thereby increasing protein lipoylation and global mRNA methylation, which led to cuproptosis and the transcriptional repression PDL1, respectively. These cascades synergistically induced immunogenic cell death in the tumors and promoted activation of CD8+ T cells, eventually leading to an antilymphoma immune response. CRUPPA19-mediated sono-immunotherapy not only eliminated the primary and metastatic lymphomas but also cleared lymphoma cells from the bone marrow. This study provided an insight into a MOF-based nanoepigenetic therapy platform with ultrasound-triggered cascade amplification for enhanced antihematological tumor immunity.

Drug delivery for platinum therapeutics

Cancer remains a severe threat to human health. Platinum drugs, such as cisplatin (CDDP), oxaliplatin, and carboplatin, are extensively utilized for treating various cancers and have become the primary drugs in first-line treatments for numerous solid tumors due to their effective anticancer properties. However, their side effects, including drug resistance, nephrotoxicity and ototoxicity, limit the clinical application. Therefore, there is an urgent need to develop targeted delivery and controlled release systems for platinum drugs to address the disadvantages, enhancing tumor accumulation and improving therapeutic effects. In this review, we first review the progress of platinum drugs, their anticancer mechanism, clinical applications and limitations. Then, we comprehensively summarize the platinum-based delivery using drug carriers and responsive strategies. We especially highlight the platinum-delivery formulations in ongoing clinical trials. Finally, we provide perspectives for this field. The review could provide an increasingly in-depth understanding of platinum therapeutics and motivate increasing delivery tactics to overcome the limitations of platinum application.

Piezoelectric-mediated two-dimensional copper-based metal-organic framework for synergistic sonodynamic and cuproptosis-driven tumor therapy

Sonodynamic therapy (SDT) is a minimally invasive therapeutic approach that utilizes sonosensitizers to catalyze substrates and generate reactive oxygen species (ROS) under ultrasound stimulation, ultimately inducing tumor cell death. Enhancing the piezoelectric properties of nanomaterials and modulating the semiconductor energy band are effective strategies to improve the catalytic efficiency of sonosensitizers. In this study, we developed a two-dimensional (2D) copper-based piezoelectric metal-organic framework (MOF) sonosensitizer, denoted as CM, through the coordination of copper and dimethylimidazole. The unique 2D MOF structure imparts CM with piezoelectric characteristics, enabling it to enhance SDT efficacy by modulating the semiconductor bandgap and carrier mobility. Upon ultrasound irradiation, CM catalyzes oxygen to undergo a cascade reaction, producing highly toxic singlet oxygen. Additionally, cupric ions in CM can be reduced by glutathione, facilitating the spontaneous catalysis of hydrogen peroxide in tumors to generate hydroxyl radicals and deplete glutathione, thereby inducing oxidative damage. Moreover, cupric ions in CM can trigger tumor cell cuproptosis, which, in combination with the generated ROS, accelerates cell death. Thus, this study establishes a MOF-based system for controllably inducing multi-pathway cancer cell death and provides a foundation for enhancing ultrasound-catalyzed tumor therapy through the optimization of piezoelectric properties.

A Novel "Three-in-One" Copper-Based Metal-Organic Framework Nanozyme Eradicates Colorectal Cancer and Overcomes Chemoresistance for Tumor Therapy

Despite considerable advancements in the treatment of colorectal cancer (CRC), the overall survival rate for patients with advanced CRC remains below 50%, primarily due to challenges posed by drug resistance and metastasis. Here, a novel "Three-in-One" Cu-based metal-organic framework nanozyme with peroxidase-like (POD-like) activity has been successfully developed, aiming to promote CRC cell death by dual targeting of oxidative stress and copper ion homeostasis, which could promote CRC cell death via apoptosis and cuproptosis, and facilitate hypoxia-inducible factor 1α (HIF-1α) degradation, leading to the reversal of chemoresistance in tumor therapy. These nanozymes, composed of copper and 2-propylimidazole (Cu-PrIm), feature a distorted Cu-N4 catalytic active center that mimics natural enzyme structures consisting of copper and histidine residues, endowing them with enzyme-like activities. The antitumor efficacy of Cu-PrIm nanozymes is validated in various in vivo models of CRC. Especially Cu-PrIm nanozymes exhibit excellent biocompatibility, biodegradability, and a tolerable toxicity profile in mouse models, making them a strong candidate for clinical translation. Taken together, the study introduces a novel therapeutic paradigm in CRC treatment by targeting these vulnerabilities and leveraging the potential using "Three-in-One" Cu-PrIm nanozymes to address multiple pathways simultaneously.

Bionic Luminescent Sensors Based on Covalent Organic Frameworks: Auditory, Gustatory, and Olfactory Information Monitoring for Multimode Perception

The synthesis of covalent organic frameworks (COFs) with excellent luminescent properties and their effective application in the field of bionic sensing remain a formidable challenge. Herein, a series of COFs with different numbers of hydroxyl groups are successfully synthesized, and the number of hydroxyl groups on the benzene-1,3,5-tricarbaldehyde (BTA) linker influences the properties of the final COFs. The COF (HHBTA-OH) prepared with hydrazine hydrate (HH) and BTA containing one hydroxyl group as the ligands exhibits the best fluorescent performance. MA@HHBTA-OH is formed by the reaction of HHBTA-OH with meldrum's acid (MA) and has its extremely high hydrophilicity, dispersibility, and strong red fluorescence, which can imitate the human gustatory system to detect bitter substances. MA@HHBTA-OH was combined with agarose (AG) to construct a MA@HHBTA-OH@AG film for assessing food freshness. In addition, an acoustic MA@HHBTA-OH@MF sensor is fabricated by integrating luminescent MA@HHBTA-OH with melamine foam (MF) through a strong hydrogen bond. MA@HHBTA-OH@MF functions like an eardrum and recognizes sound through pressure waves with excellent mechanical sensing performance. In summary, biomimetic luminescent sensors based on MA@HHBTA-OH were successfully constructed, which can monitor auditory, gustatory, and olfactory information to achieve the multimode perception of sound, bitter substances, and food freshness.

Reprogramming Dysfunctional Dendritic Cells by a Versatile Catalytic Dual Oxide Antigen-Captured Nanosponge for Remotely Enhancing Lung Metastasis Immunotherapy

Dendritic cells (DCs) play a crucial role in initiating antitumor immune responses. However, in the tumor environment, dendritic cells often exhibit impaired antigen presentation and adopt an immunosuppressive phenotype, which hinders their function and reduces their ability to efficiently present antigens. Here, a dual catalytic oxide nanosponge (DON) doubling as a remotely boosted catalyst and an inducer of programming DCs to program immune therapy is reported. Intravenous delivery of DON enhances tumor accumulation via the marginated target. At the tumor site, DON incorporates cerium oxide nanozyme (CeO2)-coated iron oxide nanocubes as a peroxide mimicry in cancer cells, promoting sustained ROS generation and depleting intracellular glutathione, i.e., chemodynamic therapy (CDT). Upon high-frequency magnetic field (HFMF) irradiation, CDT accelerates the decomposition of H2O2 and the subsequent production of more reactive oxygen species, known as Kelvin's force laws, which promote the cycle between Fe3+/Fe2+ and Ce3+/Ce4+ in a sustainable active surface. HFMF-boosted catalytic DON promotes tumors to release tumor-associated antigens, including neoantigens and damage-associated molecular patterns. Then, the porous DON acts as an antigen transporter to deliver autologous tumor-associated antigens to program DCs, resulting in sustained immune stimulation. Catalytic DON combined with the immune checkpoint inhibitor (anti-PD1) in lung metastases suppresses tumors and improves survival over 40 days.

In Situ Transformable Fibrillar Clusters Disrupt Intracellular Copper Metabolic Homeostasis by Comprehensive Blockage of Cuprous Ions Efflux

Dysregulation of copper metabolism is intricately associated with the occurrence and therapeutic management of colorectal cancer. Previous studies have attempted to induce cuproptosis by delivering lethal doses of copper ions into tumor cells, often with systemic safety risks. In vivo, transformable peptide is modular and designed for various tumor-related proteins, which can affect protein function and distribution. Here, a fibrillar transformation peptidic (FTP) nanoparticle is synthesized, which can bind ATP7B membrane proteins (cuprous ions transporter) and transform into nanofibrils/ATP7B clusters, inducing "copper-free cuproptosis" in vivo. Without adding exogenous copper ions, the spherical FTP nanoparticles bound the high distribution regions of ATP7B membrane proteins, transforming into fibrillar networks in situ with prolonged retention. The cage-like fibrillar network would further capture unbound or newly generated free ATP7B membrane proteins, thereby significantly and consistently preventing cuprous ions efflux. The FTP nanoparticles would not undergo in situ fibrillar transformation on the low expression region of ATP7B membrane proteins but enter the cell for safe degradation, which exhibited high specificity and safety in vivo. By disrupting intracellular copper homeostasis, the transformable fibrillar clusters displayed a long-term anti-tumor effect on subcutaneous transplantation and liver metastatic CRC models.

Dynamic Polymer/Metal-Organic Framework Hybrid Microcapsules for Self-Healing Anticorrosion Coatings

An ideal microcapsule effectively preserves an active substance and can rapidly release it to elicit a self-healing anticorrosion effect. However, the development of highly efficient microcapsules remains a challenge. In this study, polymer/metal-organic framework hybrid microcapsules with dynamic properties were constructed as self-healing anticorrosion coatings. The shell of the microcapsule consisted of flexible polydopamine and a hard crystalline zeolitic imidazolate framework-8 (ZIF-8) layer. The corrosion inhibitor 8-hydroxyquinoline (8-HQ) was trapped in the microcapsules and remained unreleased because the ZIF-8 layer acted as a molecular sieve. When the coating was surrounded by an acidic environment, the ZIF-8 nanocrystals in the shell dissociated, followed by the release of 8-HQ. A dense protective layer was formed on the steel surface to suppress extensive corrosion propagation. The |Z|0.01Hz value of the self-healing coating increased from 1.9 × 104 Ω cm2 to 2.2 × 106 Ω cm2 within 48 h and remained at this level until 120 h post application. This value is 3 orders of magnitude higher than that of a pure epoxy coating under the same conditions. Compared with conventional coatings, the novel dynamic microcapsules enable the application of self-healing coatings that can withstand harsh acidic environments without human intervention.

Nanocatalytic medicine enabled next-generation therapeutics for bacterial infections

The rapid rise of antibiotic-resistant strains and the persistence of biofilm-associated infections have significantly challenged global public health. Unfortunately, current clinical high-dose antibiotic regimens and combination therapies often fail to completely eradicate these infections, which can lead to adverse side effects and further drug resistance. Amidst this challenge, however, the burgeoning development in nanotechnology and nanomaterials brings hopes. This review provides a comprehensive summary of recent advancements in nanomaterials for treating bacterial infections. Firstly, the research progress of catalytic therapies in the field of antimicrobials is comprehensively discussed. Thereafter, we systematically discuss the strategies of nanomaterials for anti-bacterial infection therapies, including endogenous response catalytic therapy, exogenous stimulation catalytic therapy, and catalytic immunotherapy, in order to elucidate the mechanism of nanocatalytic anti-infections. Based on the current state of the art, we conclude with insights on the remaining challenges and future prospects in this rapidly emerging field.

Sono-promoted piezocatalysis and low-dose drug penetration for personalized therapy via tumor organoids

Chemotherapy is a widely used cancer treatment, however, it can have notable side effects owing to the high-doses of drugs administered. Sonodynamic therapy (SDT) induced by sonosensitizers has emerged as a promising approach to treat cancer, however, there is limited research evaluating its therapeutic effects on human tumors. In this study, we introduced a dual therapy that combines low-dose chemotherapeutic drugs with enhanced sonodynamic therapy, utilizing barium titanate (BaTiO3, BTO) nanoparticles (NPs) as sonosensitizers to treat tumor organoids. We demonstrated that ultrasound could improve the cellular uptake of chemotherapy drugs, while the chemotherapeutic effect of the drugs made it easier for BTO NPs to enter tumor cells, and the dual therapy synergistically inhibited tumor cell viability. Moreover, different patient-derived tumor organoids exhibited different sensitivities to this therapy, highlighting the potential to evaluate individual responses to combination therapies prior to clinical intervention. Furthermore, this dual therapy exhibited therapeutic effects equivalent to those of high-dose chemotherapy drugs on drug-resistant tumor organoids and showed the potential to enhance the efficacy of killing drug-resistant tumors. In addition, the biosafety of the BTO NPs was successfully verified in live mice via oral administration. This evidence confirms the reliable and safe nature of the dual therapy approach, making it a feasible option for precise and personalized therapy in clinical applications.

pH-Responsive injectable self-healing hydrogels loading Au nanoparticles-decorated bimetallic organic frameworks for synergistic sonodynamic-chemodynamic-starvation-chemo therapy of cancer

A novel and efficient cancer therapy was developed using a smart hydrogel containing multifunctional bimetallic organic frameworks and anticancer drugs. The injectable self-healing hydrogel with pH-responsiveness was constructed through borate ester and imine bonds among dopamine-grafted sodium alginate (SADA), hydroxypropyl chitosan (HPCS) and 2-formylphenylboronic acid (2-FPBA). The Au nanoparticles-decorated Ti/Fe bimetallic organic framework tetragonal nanosheets (Au/TF-MOF TNS) were synthesized and incorporated into the hydrogel with the anticancer drugs doxorubicin (DOX). Upon intratumoral injection of nanocomposite hydrogel, the acidic tumor microenvironment triggered the cleavage of borate ester and imine bonds, causing the hydrogel to break down and accelerating the release of both Au/TF-MOF TNS and DOX. These Au/TF-MOF TNS functioned as nanozymes, producing hydroxyl radicals (·OH) for chemodynamic therapy (CDT), generating oxygen (O2) to support sonodynamic therapy (SDT), and depleting glucose for starvation therapy (ST). Additionally, the Au/TF-MOF TNS served as sonosensitizers, capable of converting O2 into singlet oxygen (1O2) upon ultrasound irradiation to achieve SDT. Therefore, this nanocomposite hydrogel system enabled synergistic sonodynamic-chemodynamic-starvation-chemo therapy (SDT-CDT-ST-CT) of cancer, presenting a promising platform for advanced cancer therapy strategies.

Nucleus-Targeted Sonosensitizer Activates the cGAS-STING Pathway for Tumor Sonodynamic Immunotherapy

A nucleus is crucial for both sonodynamic therapy (SDT) and antitumor immunity. However, how to burst ROS generation in situ, accurately damage a nucleus, and meanwhile activate a cGAS-STING pathway-induced innate immune response are still a great challenge. Here, we present TBzT-CPi, a small molecule with a D-A-π-A1 structure that simultaneously amplifies nucleus-targeted SDT and cGAS-STING pathway-dependent immune stimulation. TBzT-CPi could accumulate in the nucleus upon ultrasound irradiation and generate ROS in situ, which damages DNA and simultaneously triggers immunogenic cell death (ICD). Stirringly, nucleus-targeting SDT not only efficiently induces apoptosis in tumor cells but also modifies the immunosuppressive tumor microenvironment by activating cytotoxic T lymphocytes, maturing dendritic cells, and secreting cytokines. These findings pave the way for developing nucleus-targeting sonosensitizers for sonodynamic immunotherapy of cancer.

Tumor Microenvironment-Responsive Zn(II)-Porphyrin Nanotheranostics for Targeted Sonodynamic Therapy

As a novel noninvasive tumor therapy, sonodynamic therapy (SDT) attracts booming concerns. However, the limited water solubility, inadequate biocompatibility, and low targeting ability of conventional sonosensitizers significantly hinder their potential for clinical application. Herein, novel zinc(II)-porphyrin nanotheranostics (HA@Zn-TCPP) were fabricated in which the zinc(II)-porphyrin (TCPP) metal-organic framework was first constructed by a simple thermal reaction, followed by the addition of hyaluronic acid (HA) for modification. The specific targeting ability of HA facilitated the internalization of HA@Zn-TCPP within tumor cells, resulting in its preferential accumulation in tumor tissues that exhibit CD44 receptor overexpression. The acidic tumor microenvironment induced the rapid decomposition of HA@Zn-TCPP, releasing free TCPP for activating SDT. This controllable generation of reactive oxygen species (ROS) could effectively decrease damage to normal tissues. The HA@Zn-TCPP exhibited remarkable antitumor effects in experiments, achieving a tumor inhibition rate of up to 82.1% when under ultrasound. This finding provides an imperative strategy to develop novel sonosensitizers for enhanced SDT.

Porphyrin-based-MOF nanocomposite hydrogels for synergistic sonodynamic and gas therapy against tumor

The glioma is one of the most aggressive tumors in humans, which is difficult to eradicate clinically. Therefore, we devised a porphyrin-based metal-organic frameworks (MOFs) crosslinking hyaluronic acid (HA) hydrogel nanocomposite through double-network (Cu-MOF-S-S-HA-Gel, CSSH-Gel), which is tumor responsive for enhanced gas therapy and sonodynamic therapy (SDT). Firstly, the hydrogels show extraordinary injectability and biocompatibility, which enables intratumor administration to circumvent the danger associated with surgery. The Cu-MOF-Cys and HA-Cys are interconnected through ether and disulfide bonds to establish a dual-network gel structure. The overexpressed glutathione (GSH) in tumor microenvironment (TME) reacts with disulfide bonds to release of the nanosensitizer (Cu-MOF). Subsequently, Cu-MOF generates reactive oxygen species (ROS) upon ultrasound irradiation for SDT, and releases L-cysteine(L-Cys) catalyzed by 3-mercapto pyruvate sulfotransferase (3-MST) to generate H2S for gas therapy. The CSSH-Gel obtained excellent synergistic anti-tumor effects (82.34 % inhibition ratio in vivo), which holds tremendous promise for the advancement of minimally invasive glioma therapies.

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.

Nanosonosensitizer Optimization for Enhanced Sonodynamic Disease Treatment

Low-intensity ultrasound-mediated sonodynamic therapy (SDT), which, by design, integrates sonosensitizers and molecular oxygen to generate therapeutic substances (e.g., toxic hydroxyl radicals, superoxide anions, or singlet oxygen) at disease sites, has shown enormous potential for the effective treatment of a variety of diseases. Nanoscale sonosensitizers play a crucial role in the SDT process because their structural, compositional, physicochemical, and biological characteristics are key determinants of therapeutic efficacy. In particular, advances in materials science and nanotechnology have invigorated a series of optimization strategies for augmenting the therapeutic efficacy of nanosonosensitizers. This comprehensive review systematically summarizes, discusses, and highlights state-of-the-art studies on the current achievements of nanosonosensitizer optimization in enhanced sonodynamic disease treatment, with an emphasis on the general design principles of nanosonosensitizers and their optimization strategies, mainly including organic and inorganic nanosonosensitizers. Additionally, recent advancements in optimized nanosonosensitizers for therapeutic applications aimed at treating various diseases, such as cancer, bacterial infections, atherosclerosis, and autoimmune diseases, are clarified in detail. Furthermore, the biological effects of the improved nanosonosensitizers for versatile SDT applications are thoroughly discussed. The review concludes by highlighting the current challenges and future opportunities in this rapidly evolving research field to expedite its practical clinical translation and application.

Albumin-based co-loaded sonosensitizer and STING agonist nanodelivery system for enhanced sonodynamic and immune combination antitumor therapy

STING agonists can activate natural and adaptive immune responses, and are expected to become a new type of immunotherapy drug for tumor therapy. However, how to target deliver STING agonists to tumor tissues is a key factor affecting the efficacy of tumor treatment. Sonodynamic therapy (SDT) has become a research hotspot in the field of cancer treatment due to its non-invasive, spatiotemporally controllable, and high tissue penetration capabilities. Therefore, how to choose the appropriate drug delivery strategy, build a suitable drug delivery system to co-deliver photosensitizers and STING agonists, is a challenge faced in the tumor treatment. In this study, we developed an albumin-based nanodelivery system named FA-ICG&MnOx@HSA that co-loaded the sonosensitizers indocyanine green (ICG) and manganese oxide (MnOx). This approach achieved folate receptor-targeting mediated tumor delivery and tumor microenvironment (TME)-responsive release facilitated by high levels of glutathione (GSH) and hydrogen peroxide (H2O2), which catalyze oxygen generation to potentiate SDT efficacy in killing tumors and inducing immunogenic cell death (ICD). Simultaneously, the released Mn2+ acted as a STING agonist promoting dendritic cell maturation, IFN-β production, and proliferation of T cells. Ultimately, this albumin based co-loaded sonosensitizer and STING agonist demonstrated promising potential for advancing tumor treatment.

A Tumor-Homing Nanoframework for Synergistic Microwave Tumor Ablation and Provoking Strong Anticancer Immunity Against Metastasis

Microwave thermotherapy (MT) is a clinical local tumor ablation modality, but its applications are limited by its therapeutic efficacy and safety. Therefore, developing sensitizers to optimize the outcomes of MT is in demand in clinical practice. Herein, we engineered a special nanoframework (i.e., FdMI) based on a fucoidan-decorated zirconium metal-organic framework incorporating manganese ions and liquid physisorption for microwave tumor ablation. The monodisperse nanoframework exhibited both microwave thermal effects and microwave dynamic effects, which could effectively kill cancer cells by efficient intracellular drug delivery. Through fucoidan-mediated targeting of P-selectin in the tumor microenvironment (TME), the FdMI effectively accumulated in tumor regions, leading to significant eradication of orthotropic triple-negative breast cancer (TNBC) and aggressive Hepa1-6 liver tumors by the synergistic effects of microwave thermotherapy/dynamic therapy (MT/MDT). The eradication of primary tumors could activate systemic immune responses, which effectively inhibited distant TNBC tumors and lung metastasis of Hepa1-6 liver tumors, respectively. This work not only engineered nanoparticle sensitizers for tumor-targeted synergistic MT/MDT but also demonstrated that nanocarrier-based microwave tumor ablation could stimulate antitumor immunity to effectively inhibit distant and metastatic tumors, demonstrating the high potential for effectively managing advanced malignant tumors.

Reactive oxygen species responsive chitooligosaccharides based nanoplatform for sonodynamic therapy in mammary cancer

Sonodynamic therapy (SDT) has been extensively studied as a new type of non-invasive treatment for mammary cancer. However, the poor water solubility and defective biocompatibility of sonosensitizers during SDT hinder the sonodynamic efficacy. Herein, a nanoplatform has been developed to achieve high efficient SDT against mammary cancer through the host-guest interaction of β-cyclodextrin/5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin (β-CD-TPP) and ferrocenecarboxylic acid/chitooligosaccharides (FC-COS). Moreover, the glucose oxidase (GOx) was loaded through electrostatic adsorption, which efficiently restricts the energy supply in tumor tissues, thus enhancing the therapeutic efficacy of SDT for tumors. Under optimal conditions, the entire system exhibited favorable water solubility, suitable particle size and viable biocompatibility. This facilitated the integration of the characteristics of starvation therapy and sonodynamic therapy, resulting in efficient inhibition of tumor growth with minimal side effects in vivo. This work may provide new insights into the application of natural oligosaccharides for construct multifunctional nanocarrier systems, which could optimize the design and development of sonodynamic therapy strategies and even combination therapy strategies.

Tailored Metal-Based Catalysts: A New Platform for Targeted Anticancer Therapies

Innovative strategies for targeted anticancer therapies have gained significant momentum, with metal complexes emerging as tunable catalysts for more effective and safer treatments. Rational design and engineering of metal complexes enable the development of tailored molecular structures optimized for precision oncology. The strategic incorporation of metal complex catalysts within combinatorial therapies amplifies their anticancer properties. This perspective highlights the advancements in synthetic strategies and rational design since 2019, showing how tailored metal catalysts are optimized by designing structures to release or in situ synthesize active drugs, leveraging the target-specific characteristics to develop more precise cancer therapies. This review explores metal-based catalysts, including those conjugated with biomolecules, nanostructures, and metal-organic frameworks (MOFs), highlighting their catalytic activity in biological environments and their in vitro/in vivo performance. To sum up, the potential of metal complexes as catalysts to reshape the landscape of anticancer therapies and foster novel avenues for therapeutic advancement is emphasized.

Functional Ginger-Derived Extracellular Vesicles-Coated ZIF-8 Containing TNF-α siRNA for Ulcerative Colitis Therapy by Modulating Gut Microbiota

Tumor necrosis factor-α (TNF-α) plays a causal role in the pathogenesis of ulcerative colitis (UC), and anti-TNF-α siRNA shows great promise in UC therapy. However, delivering siRNA with site-targeted stability and therapeutic efficacy is still challenging due to the complex and dynamic intestinal microenvironment. Here, based on the functional plant-derived ginger extracellular vesicles (EVs) and porous ZIF-8 nanoparticles, we propose a novel TNF-α siRNA delivery strategy (EVs@ZIF-8@siRNA) for UC targeted therapy. Ginger EVs show strong colon and macrophage targeting, as well as robust resistance to acidic degradation in the stomach. Moreover, 6-shogaol in ginger-derived EVs displays anti-inflammatory effects, which enhance the treatment efficiency by cooperation with TNF-α siRNA. In vitro experiments reveal that ZIF-8 nanoparticles have high TNF-α siRNA loading capacity and promote siRNA escape from cellular lysosomes. In vivo experiments show that the TNF-α level is reduced more significantly in colonic tissue than other nontargeted inflammation related factors, showing a good targeting of this composite nanoparticle. Furthermore, gut microbiota sequencing results demonstrate that the nanoparticles can promote intestinal barrier repair by regulating the intestinal microbial balance and restoring the intestinal health of UC mice. Therefore, the developed EVs@ZIF-8@siRNA nanoparticles may represent a novel colon-targeted oral drug, providing a promising therapeutic strategy for UC therapy.

Piezoelectric Bilayer Nickel-Iron Layered Double Hydroxide Nanosheets with Tumor Microenvironment Responsiveness for Intensive Piezocatalytic Therapy

Piezocatalytic therapy (PCT) based on 2D layered materials has emerged as a promising non-invasive tumor treatment modality, offering superior advantages. However, a systematic investigation of PCT, particularly the mechanisms underlying the reactive oxygen species (ROS) generation by 2D nanomaterials, is still in its infancy. Here, for the first time, biodegradable piezoelectric 2D bilayer nickel-iron layered double hydroxide (NiFe-LDH) nanosheets (thickness of ≈1.86 nm) are reported for enhanced PCT and ferroptosis. Under ultrasound irradiation, the piezoelectric semiconducting NiFe-LDH exhibits a remarkable ability to generate superoxide anion radicals, due to the formation of a built-in electric field that facilitates the separation of electrons and holes. Notably, the significant excitonic effect in the ultrathin NiFe-LDH system enables long-lived excited triplet excitons (lifetime of ≈5.04 µs) to effectively convert triplet O2 molecules into singlet oxygen. Moreover, NiFe-LDH exhibited tumor microenvironment (TME)-responsive peroxidase (POD)-like and glutathione (GSH)-depleting capabilities, further enhancing oxidative stress in tumor cells and inducing ferroptosis. To the best of knowledge, this is the first report on piezoelectric semiconducting sonosensitizers based on LDHs for PCT and ferroptosis, providing a comprehensive understanding of the piezocatalysis mechanism and valuable references for the application of LDHs and other 2D materials in cancer therapy.

Rise of Metal-Organic Frameworks: From Synthesis to E-Skin and Artificial Intelligence

Metal-organic frameworks (MOFs) have attained broad research attention in the areas of sensors, resistive memories, and optoelectronic synapses on the merits of their intriguing physical and chemical properties. In this review, recent progress on the synthesis of MOFs and their electronic applications is introduced and discussed. Initially, the crystal structures and properties of MOFs encompassing optical, electrical, and chemical properties are discussed in brief. Subsequently, advanced synthesis methods for MOFs are introduced, categorized into hydrothermal approach, microwave synthesis, mechanochemical synthesis, and electrochemical deposition. After that, the various roles of MOFs in widespread applications, including sensing, information storage, optoelectronic synapses, machine learning, and artificial intelligence, are discussed, highlighting their versatility and the innovative solutions they provide to long-standing challenges. Finally, an outlook on remaining challenges and a future perspective for MOFs are proposed.

Ultrasonic-driven degradation of organic pollutants using piezoelectric catalysts WS2/Bi2WO6 heterojunction composites

Water pollution has been made worse by the widespread use of organic dyes and their discharge, which has coincided with the industry's rapid development. Piezoelectric catalysis, as an effective wastewater purification method with promising applications, can enhance the catalyst activity by collecting tiny vibrations in nature and is not limited by sunlight. In this work, we designed and synthesized intriguing WS2/Bi2WO6 heterojunction nanocomposites, investigated their shape, structure, and piezoelectric characteristics using a range of characterization techniques, and used ultrasound to accelerate the organic dye Rhodamine B (RhB) degradation in wastewater. In comparison to the pristine monomaterials, the results demonstrated that the heterojunction composites demonstrated excellent degradation and stability of RhB under ultrasonic circumstances. The existence of heterojunctions and the internal piezoelectric field created by ultrasonic driving work in concert to boost catalytic performance, and the organic dye's rate of degradation is further accelerated by the carriers that are mutually transferred between the composites.

Sonodynamic Therapy-Driven Immunotherapy: Constructing AIE Organic Sonosensitizers Using an Advanced Receptor-Regulated Strategy

Benefit from the deeper penetration of mechanical wave, ultrasound (US)-based sonodynamic therapy (SDT) executes gratifying efficacy in treating deep-seated tumors. Nevertheless, the complicated mechanism of SDT undeniably hinders the exploration of ingenious sonosensitizers. Herein, a receptor engineering strategy of aggregation-induced emission (AIE) sonosensitizers (TPA-Tpy) with acceptor (A)-donor (D)-A' structure is proposed, which inspects the effect of increased cationizations on US sensitivity. Under US stimulation, enhanced cationization in TPA-Tpy improves intramolecular charge transfer (ICT) and accelerates charge separation, which possesses a non-negligible promotion in type I reactive oxygen species (ROS) production. Moreover, abundant ROS-mediated mitochondrial oxidative stress triggers satisfactory immunogenic cell death (ICD), which further promotes the combination of SDT and ICD. Subsequently, subacid pH-activated nanoparticles (TPA-Tpy NPs) are constructed with charge-converting layer (2,3-dimethylmaleic anhydride-poly (allylamine hydrochloride)-polyethylene glycol (DMMA-PAH-PEG)) and TPA-Tpy, achieving the controllable release of sonosensitizers. In vivo, TPA-Tpy-mediated SDT effectively initiates the surface-exposed of calreticulin (ecto-CRT), dendritic cells (DCs) maturation, and CD8+ T cell infiltration rate through enhanced ROS production, achieving suppression and ablation of primary and metastatic tumors. This study provides new opinions in regulating acceptors with eminent US sensitization, and brings a novel ICD sono-inducer based on SDT to realize superior antitumor effect.

Hierarchically Micro-, Meso-, and Macro-Porous MOF Nanosystems for Localized Cross-Scale Dual-Biomolecule Loading and Guest-Carrier Cooperative Anticancer Therapy

Mass transfer of bulky molecules, e.g., bioenzymes, particularly for cross-scale multibiomolecules, imposes serious challenges for microporous metal-organic frameworks (MOFs). Here, we create a hierarchically porous MOF heterostructure featuring highly region-ordered micro-, meso-, and macro-pores by growing a microporous ZIF-8 shell onto a hollow Prussian blue core through an epitaxial growth strategy. This allows for localized loading of large bioenzyme glucose oxidase (GOx) and small drug 5-fluorouracil (5-FU) within specific pores simultaneously and triggers unique guest-carrier cooperative anticancer capabilities. The stable ZIF-8 outer layer effectively blocks the core pores, preventing the undesired leakage of GOx into normal tissues. The acidity-induced ZIF-8 degradation gradually releases Zn2+ and loaded 5-FU for chemotherapy under acidic tumor microenvironments. With the loss of the shielding effect of the ZIF-8 coating, the released GOx depletes intratumoral glucose (Glu) for starvation therapy. Notably, an accelerated cascade reaction occurs between ZIF-8 decomposition and GOx release, facilitated by the modulator factor of Glu. This culminates in the realization of synergistic cancer therapy, as comprehensively demonstrated by in vitro and in vivo experiments, as well as transcriptome sequencing analyses. Our work not only introduces a hierarchically porous MOF heterostructure with highly region-ordered pores but also provides a perspective for guest-carrier cooperative anticancer therapy.

Two-dimensional metal organic frameworks in cancer treatment

With large specific surface area, controllable pore size, increased active sites, and structural stability, two-dimensional metal organic frameworks (2D MOFs) have emerged as promising nanomedicines in cancer therapy. These distinctive features make 2D MOFs particularly advantageous in cancer treatment and the corresponding application has gained considerable popularity, signifying significant application potential. Herein, recent advances in various applications including drug delivery and chemotherapy, photodynamic therapy, sonodynamic therapy, chemodynamic therapy, catalytic therapy, and combined therapy were summarized, with emphasis on the latest progress of new materials and mechanisms for these processes. Moreover, the current challenges, potential solutions, and possible future directions are discussed as well.

Fast fabrication of "all-in-one" injectable hydrogels as antibiotic alternatives for enhanced bacterial inhibition and accelerating wound healing

Skin wound infection has become a notable medical threat. Herein, the polysaccharide-based injectable hydrogels with multifunctionality were developed by a simple and fast gelation process not only to inactivate bacteria but also to accelerate bacteria-infected wound healing. Sodium nitroprusside (SNP) loaded PCN-224 nanoparticles were introduced into the polymer matrix formed by the dynamic and reversible coordinate bonds between Ag+ with carboxyl and amino or hydroxyl groups on carboxymethyl chitosan (CMCS), hydrogen bonds and electrostatic interactions in the polymer to fabricate SNP@PCN@Gel hydrogels. SNP@PCN@Gel displayed interconnected porous structure, excellent self-healing capacity, low cytotoxicity, good blood compatibility, and robust antibacterial activity. SNP@PCN@Gel could produce reactive oxygen species (ROS) and NO along with Fe2+, and showed long-term sustained release of Ag+, thereby effectively killing bacteria by synergistic photothermal (hyperthermia), photodynamic (ROS), chemodynamic (Fenton reaction), gas (NO) and ion (Ag+ and -NH3+ in CMCS) therapy. Remarkably, the hydrogels significantly promoted granulation tissue formation, reepithelization, collagen deposition and angiogenesis as well as wound contraction in bacteria-infected wound healing. Taken together, the strategy represented a general method to engineer the unprecedented photoactivatable "all-in-one" hydrogels with enhanced antibacterial activity and paved a new way for development of antibiotic alternatives and wound dressing.

Advances in Functionalized Biocomposites of Living Cells Combined with Metal-Organic Frameworks

Motivated by the remarkable innate characteristics of cells in living organisms, we have found that hybrid materials that combine bioorganisms with nanomaterials have significantly propelled advancements in industrial applications. However, the practical deployment of unmodified living entities is inherently limited due to their sensitivity to environmental fluctuations. To surmount these challenges, an efficacious strategy for the biomimetic mineralization of living organisms with nanomaterials has emerged, demonstrating extraordinary potential in biotechnology. Among them, innovative composites have been engineered by enveloping bioorganisms with a metal-organic framework (MOF) coating. This review systematically summarizes the latest developments in living cells/MOF-based composites, detailing the methodologies employed in structure fabrication and their diverse applications, such as bioentity preservation, sensing, catalysis, photoluminescence, and drug delivery. Moreover, the synergistic benefits arising from the individual compounds are elucidated. This review aspires to illuminate new prospects for fabricating living cells/MOF composites and concludes with a perspective on the prevailing challenges and impending opportunities for future research in this field.

Hypoxia-Specific Metal-Organic Frameworks Augment Cancer Immunotherapy of High-Intensity Focused Ultrasound

As a noninvasive treatment modality, high-intensity focused ultrasound (HIFU)-induced antitumor immune responses play a vital role in surgery prognosis. However, limited response intensity largely hinders postoperative immunotherapy. Herein, a hypoxia-specific metal-organic framework (MOF) nanosystem, coordinated by Fe3+, hypoxic-activated prodrug AQ4N, and IDO-1 signaling pathway inhibitor NLG919, is developed for the potentiating immunotherapy of HIFU surgery. The loaded AQ4N enhances the photoacoustic imaging effects to achieve accurate intraoperative navigation. Within the HIFU-established severe hypoxic environment, AQ4N is activated sequentially, following which it cooperates with Fe3+ to effectively provoke immunogenic cell death. In addition, potent NLG919 suppresses IDO-1 activity and degrades the immunosuppressive tumor microenvironment aggravated by postoperative hypoxia. In vivo studies demonstrate that the MOF-mediated immunotherapy greatly inhibits the growth of primary/distant tumors and eliminates lung metastasis. This work establishes a robust delivery platform to improve immunotherapy and the overall prognosis of HIFU surgery with high specificity and potency.

Recent advances in small-angle scattering techniques for MOF colloidal materials

This paper reviews the recent progress of small angle scattering (SAS) techniques, mainly including X-ray small angle scattering technique (SAXS) and neutron small angle scattering (SANS) technique, in the study of metal-organic framework (MOF) colloidal materials (CMOFs). First, we introduce the application research of SAXS technique in pristine MOFs materials, and review the studies on synthesis mechanism of MOF materials, the pore structures and fractal characteristics, as well as the spatial distribution and morphological evolution of foreign molecules in MOF composites and MOF-derived materials. Then, the applications of SANS technique in MOFs are summarized, with emphasis on SANS data processing method, structure modeling and quantitative structural information extraction. Finally, the characteristics and developments of SAS techniques are commented and prospected. It can be found that most studies on MOF materials with SAS techniques focus mainly on nanoporous structure characterization and the evolution of pore structures, or the spatial distribution of other foreign molecules loaded in MOFs. Indeed, SAS techniques take an irreplaceable role in revealing the structure and evolution of nanopores in CMOFs. We expect that this paper will help to understand the research status of SAS techniques on MOF materials and better to apply SAS techniques to conduct further research on MOF and related materials.

Advancements and Challenges in the Application of Metal-Organic Framework (MOF) Nanocomposites for Tumor Diagnosis and Treatment

Nanoscale metal-organic frameworks (MOFs) offer high biocompatibility, nanomaterial permeability, substantial specific surface area, and well-defined pores. These properties make MOFs valuable in biomedical applications, including biological targeting and drug delivery. They also play a critical role in tumor diagnosis and treatment, including tumor cell targeting, identification, imaging, and therapeutic methods such as drug delivery, photothermal effects, photodynamic therapy, and immunogenic cell death. The diversity of MOFs with different metal centers, organics, and surface modifications underscores their multifaceted contributions to tumor research and treatment. This review is a summary of these roles and mechanisms. The final section of this review summarizes the current state of the field and discusses prospects that may bring MOFs closer to pharmaceutical applications.

Positron emission tomography guided synergistic treatment of melanoma using multifunctional zirconium-hematoporphyrin nanosonosensitizers

Sonodynamic therapy (SDT) has emerged as a useful approach for tumor treatment. However, its widespread application is impeded by poor pharmacokinetics of existing sonosensitizers. Here we developed a metal-organic nanoplatform, wherein a small-molecule sonosensitizer (hematoporphyrin monomethyl ether, HMME) was ingeniously coordinated with zirconium, resulting in a multifunctional nanosonosensitizer termed Zr-HMME. Through post-synthetic modifications involving PEGylation and tumor-targeting peptide (F3) linkage, a nanoplatform capable of homing on melanoma was produced, which could elicit robust immune responses to suppress tumor lung metastasis in the host organism. Importantly, after seamless incorporation of positron-emitting 89Zr into this nanosonosensitizer, positron emission tomography (PET) could be used to monitor its in vivo pharmacokinetics. PET imaging studies revealed that this nanoplatform exhibited potent tumor accumulation and strong in vivo stability. Using intrinsic fluorescence from HMME, a dual-modal diagnostic capability (fluorescence and PET) was confirmed for this nanosonosensitizer. In addition, the mechanisms of how this nanoplatform interacted with immune system were also investigated. The collective data proved that the coordination structure between small-molecule drug cargos and metals may enhance the functions of each other while mitigating their weaknesses. This straightforward approach can expand the potential applications of suitable drug molecules.

Chemodynamic PtMn Nanocubes for Effective Photothermal ROS Storm a Key Anti-Tumor Therapy in-vivo

Background

Chemodynamic therapy (CDT) is a new treatment approach that is triggered by endogenous stimuli in specific intracellular conditions for generating hydroxyl radicals. However, the efficiency of CDT is severely limited by Fenton reaction agents and harsh reaction conditions.

Methods

Bimetallic PtMn nanocubes were rationally designed and simply synthesized through a one-step high-temperature pyrolysis process by controlling both the nucleation process and the subsequent crystal growth stage. The polyethylene glycol was modified to enhance biocompatibility.

Results

Benefiting from the alloying of Pt nanocubes with Mn doping, the structure of the electron cloud has changed, resulting in different degrees of the shift in electron binding energy, resulting in the increasing of Fenton reaction activity. The PtMn nanocubes could catalyze endogenous hydrogen peroxide to toxic hydroxyl radicals in mild acid. Meanwhile, the intrinsic glutathione (GSH) depletion activity of PtMn nanocubes consumed GSH with the assistance of Mn3+/Mn2+. Upon 808 nm laser irradiation, mild temperature due to the surface plasmon resonance effect of Pt metal can also enhance the Fenton reaction.

Conclusion

PtMn nanocubes can not only destroy the antioxidant system via efficient reactive oxygen species generation and continuous GSH consumption but also propose the photothermal effect of noble metal for enhanced Fenton reaction activity.

High-Z elements dominated bismuth-based heterojunction nano-semiconductor for radiotherapy-enhanced sonodynamic breast cancer therapy

Ultrasound and X-rays possess remarkable tissue penetration capabilities, making them promising candidates for cancer therapy. Sonodynamic therapy, which utilizes ultrasound excitation, offers a safer alternative to radiotherapy and can be combined with X-rays to mitigate the adverse effects on normal tissues. In this study, we developed a bismuth-based heterostructure semiconductor (BFIP) to enhance the efficacy of radiotherapy and sonodynamic therapy in treating breast cancer. The semiconductor is fabricated through a two-step process involving the synthesis of porous spherical bismuth fluoride and partially reduced to bismuth oxyiodide. Then, followed by surface modification with amphiphilic polyethylene glycol, BFIP is fabricated. Incorporating heavy atoms in the BFIP enhances radiosensitivity. The BFIP exhibits superior carrier separation efficiency compared to bismuth fluoride, generating a substantial quantity of reactive oxygen species upon ultrasound stimulation. Moreover, the BFIP effectively depletes glutathione through coordination and hole-mediated oxidation pathways, disrupting the tumor microenvironment and inducing oxidative stress. Encouraging results are acquired in both in vitro cell and in vivo tumor models. Our study provides a de-risking strategy by utilizing ultrasound as a partial substitute for X-rays in treating deep-seated tumors, offering a viable research direction for constructing a unified nanoplatform.

Adavosertib-encapsulated metal-organic frameworks for p53-mutated gallbladder cancer treatment via synthetic lethality

Adavosertib (ADA) is a WEE1 inhibitor that exhibits a synthetic lethal effect on p53-mutated gallbladder cancer (GBC). However, drug resistance due to DNA damage response compensation pathways and high toxicity limits further applications. Herein, estrone-targeted ADA-encapsulated metal-organic frameworks (ADA@MOF-EPL) for GBC synthetic lethal treatment by inducing conditional factors are developed. The high expression of estrogen receptors in GBC enables ADA@MOF-EPL to quickly enter and accumulate near the cell nucleus through estrone-mediated endocytosis and release ADA to inhibit WEE1 upon entering the acidic tumor microenvironment. Ultrasound irradiation induces ADA@MOF-EPL to generate reactive oxygen species (ROS), which leads to a further increase in DNA damage, resulting in a higher sensitivity of p53-mutated cancer cells to WEE1 inhibitor and promoting cell death via conditional synthetic lethality. The conditional factor induced by ADA@MOF-EPL further enhances the antitumor efficacy while significantly reducing systemic toxicity. Moreover, ADA@MOF-EPL demonstrates similar antitumor abilities in other p53-mutated solid tumors, revealing its potential as a broad-spectrum antitumor drug.

A metal-organic framework (MOF) built on surface-modified Cu nanoparticles eliminates tumors via multiple cascading synergistic therapeutic effects

Tumors produce a hypoxic environment that greatly influences cancer treatment, and conventional chemotherapeutic drugs cannot selectively accumulate in the tumor region because of the lack of a tumor targeting mechanism, causing increased systemic toxicities and side effects. Hence, designing and developing new nanoplatforms that combine multimodal therapeutic regimens is essential to improve tumor therapeutic efficacy. Herein, we report the synthesis of ultrafine Cu nanoparticles loaded with a drug combination of cisplatin (Pt) and 1-methyl-d-tryptophan (1-MT) and externally coated with 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP) photosensitizer, polydopamine (PDA) and CaO2 of MIL-101(Fe) as a new nanoplatform (Cu@MIL-101@PMTPC). The nanoplatform synergistically combined chemodynamic therapy (CDT), photodynamic therapy (PDT), and immunochemotherapy. The Fe3+ in MIL-101(Fe) and the surface Cu nanoparticles exhibited strong ability to consume intracellular glutathione (GSH), thereby generating a Fenton-like response in the tumor microenvironment (TME) with substantial peroxidase (POD)-like and superoxide dismutase (SOD)-like activities. In this design, we used the indoleamine 2,3-dioxygenase (IDO) inhibitor 1-MT to overcome chemotherapy-induced immune escape phenomena including enhanced CD8+ and CD4+ T cell expression, interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) production, and accelerated immunogenic cell death. The targeted release of cisplatin loaded into Cu@MIL-101@PMTPC also reduced toxic side effects of chemotherapy. TCPP generated a large amount of singlet oxygen (1O2) upon specific laser irradiation to effectively kill tumor cells. CaO2 on the outer layer generated oxygen (O2) and hydrogen peroxide (H2O2) to ameliorate hypoxia in the tumor microenvironment, enhance the PDT effect, and provide a continuous supply of H2O2 for the Fenton-like reaction. Thus, this nanocarrier platform exhibited a powerful chemodynamic, photodynamic, and immunochemotherapeutic cascade, providing a new strategy for cancer treatment.

Current status of controlled onco-therapies based on metal organic frameworks

Despite consecutive efforts devoted to the establishment of innovative therapeutics for cancer control, cancer remains as a primary global public health concern. Achieving controlled release of anti-cancer agents may add great value to the field of oncology that requires the involvement of nanotechnologies. Metal organic frameworks (MOFs) hold great promise in this regard owing to their unique structural properties. MOFs can act as superior candidates for drug delivery given their porous structure and large loading area, and can be prepared into anti-cancer therapeutics by incorporating stimuli-sensitive components into the ligands or nodes of the framework. By combing through chemical and physical features of MOFs favorable for onco-therapeutic applications and current cancer treatment portfolios taking advantages of these characteristics, this review classified MOFs feasible for establishing controlled anti-cancer modalities into 6 categories, outlined the corresponding strategies currently available for each type of MOF, and identified understudied areas and future opportunities towards innovative MOF design for improved or expanded clinical anti-cancer applications.

Heterometallic MIL-125(Ti-Al) frameworks for electrochemical determination of ascorbic acid, dopamine and uric acid

The detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA) is not only of great significance in the areas of biomedicine and neurochemistry but also helpful in disease diagnosis and pathology research. Due to their diverse structures, designability, and large specific surface areas, metal-organic frameworks (MOFs) have recently caught considerable attention in the electrochemical field. Herein, a family of heterometallic MOFs with amino modification, MIL-125(Ti-Al)-xNH2 (x = 0%, 25%, 50%, 75%, and 100%), were synthesized and employed as electrochemical sensors for the detection of AA, DA, and UA. Among them, MIL-125(Ti-Al)-75%NH2 exhibited the most promising electrochemical behavior with 40% doping of carbon black in 0.1 M PBS (pH = 7.10), which displayed individual detection performance with wide linear detection ranges (1.0-6.5 mM for AA, 5-100 μM for DA and 5-120 μM for UA) and low limits of detection (0.215 mM for AA, 0.086 μM for DA, and 0.876 μM for UA, S/N = 3). Furthermore, the as-prepared MIL-125(Ti-Al)-75%NH2/GCE provided a promising platform for future application in real sample analysis, owing to its excellent anti-interference performance and good stability.

Mn(II) Optimized Sono/Chemodynamic Effect of Porphyrin-Metal-Organic Framework Nanosheets for MRI-Guided Colon Cancer Therapy and Metastasis Suppression

Sonodynamic therapy (SDT) offers a remarkable non-invasive ultrasound (US) treatment by activating sonosensitizer and generating reactive oxygen species (ROS) to inhibit tumor growth. The development of multifunctional, biocompatible, and highly effective sonosensitizers remains a current priority for SDT. Herein, the first report that Mn(II) ions chelated Gd-TCPP (GMT) nanosheets (NSs) are synthesized via a simple reflux method and encapsulated with pluronic F-127 to form novel sonosensitizers (GMTF). The GMTF NSs produce a high yield of ROS under US irradiation due to the decreased highest occupied molecular orbital-lowest unoccupied molecular orbital gap energy (2.7-1.28 eV). Moreover, Mn(II) ions endow GMTF with a fascinating Fenton-like activity to produce hydroxyl radicals in support of chemodynamic therapy (CDT). It is also effectively used in magnetic resonance imaging (MRI) with high relaxation rate (r 1: 4.401 mM-1 s-1) to track the accumulation of NSs in tumors. In vivo results indicate that the SDT and CDT in combination with programmed cell death protein 1 antibody (anti-PD-1) show effective metastasis prevention effects, and 70% of the mice in the GMTF + US + anti-PD-1 group survived for 60 days. In conclusion, this study develops a sonosensitizer with promising potential for utilizing both MRI-guided SDT and CDT strategies.

Ultrasound-Responsive Nanodroplet-Based Targeted Therapy via Conversion to Microbubbles

Ultrasound-based therapy is appealing as it can be used via a wireless approach at remote parts of the body including the brain. Microbubbles are commonly used in such therapy due to their highly sound-responsive property. However, the larger size of microbubbles limits selective targeting in vitro/in vivo. Here, we report the design of nanodroplets of 70-130 nm in size that can be easily converted to microbubbles via ultrasound exposure. The advantage of this approach is that smaller nanodroplets can be used for cell/subcellular targeting, and next, they can be used for therapy by converting to microbubbles. More specifically, folate/dopamine-terminated perfluorohexane nanodroplets are designed that are loaded with a molecular drug. These nanodroplets are used for selective cell targeting, followed by ultrasound-induced microbubble conversion that is associated with drug release and intracellular reactive oxygen species generation. This approach has been used for selective cell therapy applications. The designed nanodroplet and approach can be used for the enhanced therapeutic performance of existing drugs.

Structure Engineered High Piezo-Photoelectronic Performance for Boosted Sono-Photodynamic Therapy

Sono-photodynamic therapy is hindered by the limited tissue penetration depth of the external light source and the quick recombination of electron-hole owing to the random movement of charge carriers. In this study, orthorhombic ZnSnO3 quantum dots (QDs) with piezo-photoelectronic effects are successfully encapsulated in hexagonal upconversion nanoparticles (UCNPs) using a one-pot thermal decomposition method to form an all-in-one watermelon-like structured sono-photosensitizer (ZnSnO3 @UCNPs). The excited near-infrared light has high penetration depth, and the watermelon-like structure allows for full contact between the UCNPs and ZnSnO3 QDs, achieving ultrahigh Förster resonance energy transfer efficiency of up to 80.30%. Upon ultrasonic and near-infrared laser co-activation, the high temperature and pressure generated lead to the deformation of the UCNPs, thereby driving the deformation of all ZnSnO3 QDs inside the UCNPs, forming many small internal electric fields similar to isotropic electric domains. This piezoelectric effect not only increases the internal electric field intensity of the entire material but also prevents random movement and rapid recombination of charge carriers, thereby achieving satisfactory piezocatalytic performance. By combining the photodynamic effect arising from the energy transfer from UCNPs to ZnSnO3 , synergistic efficacy is realized. This study proposes a novel strategy for designing highly efficient sono-photosensitizers through structural design.

A metal-organic framework-integrated composite for piezocatalysis-assisted tumour therapy: design, related mechanisms, and recent advances

With the growing need for more effective tumour treatment, piezocatalytic therapy has emerged as a promising approach due to its distinctive capacities to generate ROS through stress induction and regulate the hypoxic state of the TME. MOF-based piezocatalysts not only possess the benefits of piezocatalysis but also exhibit several advantages associated with MOFs, such as tunable pore size, large specific surface area, and good biocompatibility. Therefore, they are expected to become a powerful promoter of piezocatalytic therapy. This review elaborates on the fundamental principles of piezocatalysis and summarises recent advances in the piezocatalytic therapy and combination therapies of tumours, generalising the strategies for constructing piezocatalytic systems based on MOFs. Finally, the challenges confronted and future opportunities for the design and application of piezocatalytic MOF anticancer systems have been discussed.