Metal-Organic Framework Nanocarriers for Drug Delivery in Biomedical Applications

The potential of metal-organic framework MIL-101(Al)-NH2 in the forefront of antiviral protection of cells via interaction with SARS-CoV-2 spike RBD protein and their antibacterial action mediated with hypericin and photodynamic treatment

The global pandemic of SARS-CoV-2 has highlighted the necessity for innovative therapeutic solutions. This research presents a new formulation utilising the metal-organic framework MIL-101(Al)-NH2, which is loaded with hypericin, aimed at addressing viral and bacterial challenges. Hypericin, recognised for its antiviral and antibacterial efficacy, was encapsulated to mitigate its hydrophobicity, improve bioavailability, and utilise its photodynamic characteristics. The MIL-101(Al)-NH2 Hyp complex was synthesised, characterised, and evaluated for its biological applications for the first time. The main objective of this study was to demonstrate the multimodal potential of such a construct, in particular the effect on SARS-CoV-2 protein levels and its interaction with cells. Both in vitro and in vivo experiments demonstrated the effective transport of hypericin to cells that express ACE2 receptors, thereby mimicking mechanisms of viral entry. In addition, hypericin found in the mitochondria showed selective phototoxicity when activated by light, leading to a decrease in the metabolic activity of glioblastoma cells. Importantly, the complex also showed antibacterial efficacy by selectively targeting Gram-positive Staphylococcus epidermidis compared to Gram-negative Escherichia coli under photodynamic therapy (PDT) conditions. To our knowledge, this study was the first to demonstrate the interaction between hypericin, MIL-101(Al)-NH2 and the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein, which inhibits cellular uptake and colocalises with ACE2-expressing cells. Therefore, the dual functionality of the complex - targeting the viral RBD and the antibacterial effect via PDT - emphasises its potential to mitigate complications of viral infections, such as secondary bacterial infections. In summary, these results suggest that MIL-101(Al)-NH2 Hyp is a promising multifunctional therapeutic agent for antiviral and antibacterial applications, potentially contributing to the improvement of COVID-19 treatment protocols and the treatment of co-infections.

Targeting lipid metabolism via nanomedicine: A prospective strategy for cancer therapy

Lipid metabolism has been increasingly recognized to play an influencing role in tumor initiation, progression, metastasis, and therapeutic drug resistance. Targeting lipid metabolic reprogramming represents a promising therapeutic strategy. Despite their structural complexity and poor targeting efficacy, lipid-metabolizing drugs, either used alone or in combination with chemotherapeutic agents, have been employed in clinical practice. The advent of nanotechnology offers new approaches to enhancing therapeutic effects, includingthe targeted delivery and integration of lipid metabolic reprogramming with chemotherapy, photodynamic therapy (PDT), and immunotherapy. The integrated nanoformulation, nanomedicine, could significantly advance the field of lipid metabolism therapy. In this review, we will briefly introduce the concept of cancer lipid metabolism reprogramming, then elaborate the latest advances in engineered nanomedicine for targeting lipid metabolism during cancer treatment, and finally provide our insights into future perspectives of nanomedicine for interference with lipid metabolism in the tumor microenvironment.

Multifunctional metal-organic frameworks in breast cancer therapy: Advanced nanovehicles for effective treatment

Breast cancer is the second-most common cause of cancer-related death among women worldwide, with a gradual annual increase of 0.5 % in its occurrence rate in recent years. This complex ailment exhibits considerable diversity, with a mortality rate of 2.5 %. One promising area of research for its treatment is the development of MOFs, which are intricate three-dimensional (3D) structures constructed from metal ions or clusters joined with organic ligands through coordinate bonds. MOFs have emerged as versatile platform overcoming the limitations of conventional chemotherapeutics including poor drug solubility, non-specific targeting, and multidrug resistance. These applications are attributed to their adjustable porosity, chemical makeup, dimensions, straightforward surface customization capabilities, biocompatibility, nontoxicity etc. These properties position MOFs as excellent candidates for diverse regimes of cancer therapeutics including innovative approaches such as phototherapy, chemotherapy, immunotherapy, gene therapy, sonodynamic therapy, and various combination therapies. The article emphasizes the functionalization and applications of MOFs, with a primary focus on their therapeutic capabilities, synergistic approaches, and theranostic strategies that integrate diagnostic and therapeutic functions. Strategies to improve MOF biocompatibility and stability, such as surface modifications and biocompatible coatings are also discussed. Insights on various challenges and future prospects are provided to address current limitations and inspire further research, paving the way for clinical translation of MOF-based breast cancer therapies.

Advanced Solid Lubrication with COK-47: Mechanistic Insights on the Role of Water and Performance Evaluation

Metal-organic framework (MOF) nanoparticles have attracted widespread attention as lubrication additives due to their tunable structures and surface effects. However, their solid lubrication properties have been rarely explored. This work introduces the positive role of moisture in solid lubrication in the case of a newly described Ti-based MOF (COK-47) powder. COK-47 achieves an 8.5-fold friction reduction compared to AISI 304 steel-on-steel sliding under room air. In addition, COK-47 maintains a similarly low coefficient of friction (0.1-0.2) on various counterbodies, including Al2O3, ZrO2, SiC, and Si3N4. Notably, compared to other widely studied MOFs (ZIF-8, ZIF-67) and 2D materials powder (MXene, TMD, rGO), COK-47 exhibits the lowest friction (≈0.1) under the same experimental settings. Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, scanning electron microscope, and transmission electron microscopy indicate that the tribofilm is an amorphous film obtained by hydrolysis of COK-47 in the air with moisture. Density functional theory further confirms that water catalyzes the decomposition of COK-47, a crucial step in forming the tribofilm. This study demonstrates the idea of utilizing MOF and water-assisted lubrication mechanisms. It provides new insights into MOF applications in tribology and highlights interdisciplinary contributions of mechanical engineering and chemistry.

Zeolitic Imidazole Framework-8 Nanoparticles as an Alternative to Freund's Adjuvant for Klebsiella pneumoniae Recombinant Protein Vaccine

Vaccination represents a promising approach to combat resistant Klebsiella pneumoniae (KP). However, there is currently no licensed vaccine in the veterinary field. Outer membrane proteins have been proven to possess good immunogenicity, but Freund's adjuvant, which is commonly used to administer protein vaccines, has limitations such as a complicated formulation process as well as a tendency to cause pain and inflammation in animals. Here, we prepared a nano-vaccine based on zeolitic imidazolate framework-8 (ZIF-8)-encapsulated outer membrane protein PhoE and evaluated its efficiency in enhancing humoral and cellular immune responses in BALB/c mice. ZIF-8 nanoparticles rapidly delivered the protein antigen into dendritic cells and successfully activated them. In addition, significantly higher IgG antibody titers, cytokine levels, and splenocyte proliferation indices were founded in mice subcutaneously immunized with PhoE@ZIF-8 than in those receiving free PhoE alone. In a BALB/c mouse model, PhoE@ZIF-8 elicited a strong immune response with improved prophylactic efficacy against KP that was similar to the Freund's adjuvant-formulated vaccine. Based on the superiority of this nano-vaccine with good biocompatibility, inexpensive preparation and higher efficiency of delivering antigen into cells, ZIF-8 can serve as a promising replacement for Freund's adjuvant in research, with a prospective usage for vaccines against bacterial pathogens in the veterinary field.

Synergistic action of combining photodynamic therapy with immunotherapy for eradicating solid tumors in animal models: A systematic review

Malignancies maintain a high rate of mortality worldwide each year, requiring the development of novel therapeutic platforms. Immunotherapy approaches are considered a revolutionary treatment for overcoming malignancies. Photodynamic therapy (PDT) has attracted significant attention in various cancer types. Recent progress in cancer therapies has underscored the potential of combining PDT with immunotherapy. This approach can improve therapeutic outcomes by directly eliminating tumor cells and boosting immune responses for sustained anti-tumor effects in the whole body. This study aims to determine the relative efficacy of combining PDT with immunotherapy compared to PDT alone. Following the PRISMA guidance, an extensive literature review was conducted utilizing Scopus, Web of Science, and PubMed to identify high-quality preclinical studies exploring various aspects of PDT combined with immunotherapy. The adopted PICO framework included studies with rigorous experimental designs and relevant outcomes. The present review reveals the characteristics of tumor models, delivery systems, photosensitizers, and immunotherapy approaches. Key findings indicate that the combined PDT-immunotherapy approach shows promise in treating multiple tumors according to their size, therapeutic biomarkers, and inhibition of distant tumors. Finally, this integrated therapeutic strategy holds significant promise for advancing cancer treatment paradigms by potentiating each treatment efficacy; however, its clinical utility requires careful consideration of the associated challenges.

Advances of functional nanomaterials as either therapeutic agents or delivery systems in the treatment of periodontitis

Periodontitis is a common chronic inflammatory disease primarily caused by pathogenic microorganisms in the oral cavity. Without appropriate treatments, it may lead to the gradual destruction of the supporting tissues of the teeth. While current treatments can alleviate symptoms, they still have limitations, particularly in eliminating pathogenic bacteria, promoting periodontal tissue regeneration, and avoiding antibiotic resistance. In recent years, functional nanomaterials have shown great potential in the treatment of periodontitis due to their unique physicochemical and biological properties. This review summarizes various functionalization strategies of nanomaterials and explores their potential applications in periodontitis treatment, including metal-based nanoparticles, carbon nanomaterials, polymeric nanoparticles, and exosomes. The mechanisms and advances in antibacterial effects, immune regulation, reactive oxygen species (ROS) scavenging, and bone tissue regeneration are discussed in detail. In addition, the challenges and future directions of applying nanomaterials in periodontitis therapy are also discussed.

Mannosylated MOF Encapsulated in Lactobacillus Biofilm for Dual-Targeting Intervention Against Mammalian Escherichia coli Infections

Pathogenic bacterial infections pose a major concern, especially concerning mammalian enteritis and diarrhea. Compared to conventional antibiotic intervention, metal-organic frameworks (MOFs) exhibit superior antibacterial properties and lower cytotoxicity, demonstrating great promise in the treatment of pathogen-induced diarrhea. However, the achievement of their precise targeted delivery is still a significant challenge. Herein, a novel precision nano-system with a dual-targeting approach for treating intestinal infections caused by Escherichia coli (E. coli) is designed. First, Zn-MOF was synthesized based on ZnO, which possessed enhanced elimination of planktonic bacteria and biofilms. Through mannosylation, Zn-MOF@Man specifically recognized the FimH pili of E. coli, leading to its aggregation and subsequent eradication. Second, guided by whole genome sequencing, the encapsulation of Lactobacillus biofilm exertd immunomodulatory function, overcomed challenges related to intestinal targeting, and facilitated sustained drug release. Furthermore, Zn-MOF@Man/LRB maintaind microbiota equilibrium and promoted stem cell differentiation and barrier stability, ensuring consistent anti-diarrheal and anti-inflammatory efficacy in mice, piglets, and humans. This approach represents a novel dual-targeting antimicrobial strategy, combining probiotic biofilms and E. coli-oriented delivery, advancing safe and effective treatment that restores intestinal homeostasis for potential applications in both human medicine and animal husbandry.

Halogen anion modulated metal-organic frameworks with enhanced nanozyme activities for bacterial biofilm disruption

There is an urgent need to develop new nanozymes with enhanced catalytic activities to combat bacterial infections, which have become increasingly challenging due to the misuse of antibiotics and the difficulties of new antibiotic discovery. Here, we employed a new strategy against bacterial biofilms by introducing halide anions to modulate the crystal facets of ZIF-L metal-organic frameworks (MOFs) and then loading chloroquine to form Ch@ZIF-L. The modulation of crystal facets significantly enhanced the oxidase activities of ZIF-L, which can be significantly changed by modulation of its crystal facets, with the hexagonal ZIF-L (ZIF-L-H-Cl) structure showing the highest oxidase activity. At pH 6.0, over 80% of chloroquine was released from Ch@ZIF-L-H-Cl within 8 hours, altering the DNA conformation of bacterial biofilms and disrupting the extracellular polymeric substances (EPSs). The generation of singlet oxygen catalyzed by ZIF-L-H-Cl can effectively kill bacteria at the infected wound site. The composite nanozyme of Ch@ZIF-L-H-Cl, when treated at 100 μg mL-1, exhibited no adverse effects on normal cell growth or hemolysis. Our in vivo experiments demonstrated an 85% reduction of the wound area by day 8 and a rapid recovery of body weight in mice with wounds infected with Staphylococcus aureus (S. aureus) biofilms. Furthermore, substantial reductions in bacterial counts were observed in both wounds and blood samples in the mice, highlighting the great potential of Ch@ZIF-L-H-Cl in combating bacterial biofilm infections.

Engineered Metal-Organic Frameworks for Targeted CRISPR/Cas9 Gene Editing

The development of precise and efficient delivery systems is pivotal for advancing CRISPR/Cas9 gene-editing technologies, particularly for therapeutic applications. Engineered metal-organic frameworks (MOFs) have emerged as a promising class of inorganic nonviral vectors, offering unique advantages such as tunable porosity, high cargo-loading capacity, and biocompatibility. This review explores the design and application of MOF-based nanoplatforms tailored for the targeted delivery of CRISPR/Cas9 components, aiming to enhance gene-editing precision and efficiency. By incorporating stimuli-responsive linkers and bioactive ligands, these MOFs enable controlled release of CRISPR/Cas9 payloads at the target site. Comparative discussions demonstrate superior performance of MOFs over conventional nonviral systems in terms of stability, transfection efficiency, and reduced off-target effects. Additionally, the intracellular trafficking mechanisms and the therapeutic potential of these platforms in preclinical models are discussed. These findings highlight the transformative potential of MOF-based delivery systems in overcoming the challenges associated with gene-editing technologies, such as immunogenicity and cytotoxicity, paving the way for their application in precision medicine. This review provides a blueprint for the integration of nanotechnology and genome editing, advancing the frontier of nonviral therapeutic delivery systems.

Engineering Dual-Responsive Nanoplatform Achieves Copper Metabolism Disruption and Glutathione Consumption to Provoke Cuproptosis/Ferroptosis/Apoptosis for Cancer Therapy

Cuproptosis is a new copper-dependent form of regulated cell death and shows enormous promise in cancer therapy. However, its therapeutic performance is compromised by the strictly regulated copper metabolism and highly expressed intracellular glutathione (GSH). Herein, an intelligent nanoplatform (NSeMON-P@CuT/LipD) is rationally developed as a copper metabolic disrupter, GSH consumer, and Fenton-like reaction trigger for cancer cuproptosis/ferroptosis/apoptosis therapy. NSeMON-P@CuT/LipD is constructed from the preparation of diselenide-bridged mesoporous organosilica nanoparticles, and then pemetrexed (Pem) is loaded followed by surface deposition with a Cu2+-3,3'-dithiobis(propionohydrazide) (TPH) coordinated network and coating with a diclofenac (DC)-encapsulated liposome. In response to the specific tumor microenvironment, the obtained NSeMON-P@CuT/LipD can release DC, Cu2+, and Pem and simultaneously amplify cellular oxidative stress by consuming GSH and catalyzing endogenous H2O2 into hydroxyl radicals (•OH). Both liberated DC and augmented oxidative stress can inhibit glycolysis, reduce ATP level, and then block copper transporter ATP7B, resulting in metabolic disorders and the high retention of copper in cells for •OH generation. Moreover, the overloaded copper can promote dihydrolipoamide S-acetyltransferase oligomerization and Fe-S cluster protein loss, thus evoking cuproptosis. Collectively, the augmented oxidative stress activates prominent ferroptosis, which cooperates with cuproptosis and Pem-mediated apoptosis to significantly inhibit the tumor growth of 4T1 tumor-bearing mice. This study demonstrates feasible strategies to enhance tumor cuproptosis using a single nanoplatform and may also inspire the design of advanced cuproptosis-related therapies.

Strengthening Antisense Oligonucleotide-Mediated Anti-Tumor Immunity via Metal-Organic Framework Nanoparticles

Overexpression of checkpoint proteins, such as programmed death ligand one (PD-L1), prevents immune recognition and enables cancer growth. Current monoclonal antibodies that block PD-L1 tend to be fragile, unable to penetrate tumors, and target cancer at later stages, thus leading to inconsistent patient outcomes. Antisense oligonucleotides (ASOs) provide an alternative to decrease PD-L1 expression, but require frequent high dosing due to fast degradation, rapid clearance, and poor cell uptake. To overcome these issues, we harnessed biocompatible metal-organic framework (MOF) nanoparticles, porous nanomaterials comprising metal nodes and organic linkers, to deliver ASOs. Encapsulating ASOs into MOFs enhances their stability and protection during intracellular delivery, leading to reduced PD-L1 expression and downstream immune recognition. Herein, we synthesized three distinct PD-L1-specific ASOs and loaded them individually into zirconium-based nano-sized NU-1000 MOFs, averaging ∼80% encapsulation efficiency. Release of encapsulated ASOs was sustained up to 7 days ex cellulo . MOF encapsulation increased ASO potency and reduced PD-L1 expression ∼ 3-fold and 2-fold in triple negative breast cancer EMT6 and melanoma B16-F10 cells, respectively. We evaluated the impact of MOF-delivered ASOs on PD-L1-expressing immune cells, where we observed ca. 12-fold increases in dendritic cell co-stimulatory marker expression, and amplified T cell activation and proliferation compared to untreated cells (4-fold and 10-fold, respectively). Notably, these changes drove a 3-fold increase in tumor caspase-3 expression, a key mediator for apoptosis. This research highlights how MOFs can be harnessed to bypass ASO limitations without requiring sequence modifications, and offers a broadly applicable platform for improved oligonucleotide delivery for various genes of interest.

Functionalized zeolite regulates bone metabolic microenvironment

The regulation of bone metabolic microenvironment imbalances in diseases such as osteoporosis, bone defects, infections, and tumors remains a significant challenge in orthopedics. Therefore, it has become urgent to develop biomaterials with effective bone metabolic microenvironmental regulatory functions. Zeolites, as advanced biomedical materials, possess distinctive physicochemical properties such as multi-level pore structures, adjustable frameworks, easily modifiable surfaces, and excellent adsorption capabilities. These advantageous characteristics give zeolites broad application prospects in regulating the bone metabolic microenvironment. Therefore, this paper first classifies zeolites used to regulate the bone metabolic microenvironment based on their topological structures and compositional frameworks. Subsequently, it provides a detailed description of modification strategies for zeolite materials aimed at regulating this microenvironment. Next, a comprehensive summary was provided on the preparation strategies for zeolite materials aimed at regulating the bone metabolic microenvironment. Additionally, the paper focuses on the specific applications of zeolite materials in conditions of bone metabolic imbalance, such as osteoporosis, bone defects, orthopedic infections, and bone tumors, highlighting their potential in enhancing osteogenic microenvironments, controlling infections, and treating bone tumors. Finally, it outlines the prospects and challenges associated with the application of zeolites in regulating the bone metabolic microenvironment. This review comprehensively summarizes zeolites used for bone metabolic regulation, aiming to provide guidance for future research and application development.

Dual-modality immune nano-activator harnessing Mn2⁺ and quercetin to potentiate the cGAS-STING pathway for advanced cancer metalloimmunotherapy

Manganese ions (Mn2+) have emerged as promising activators of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway. However, their clinical application was hindered by low bioavailability and limited immune activation pathways, which impaired their ability to trigger robust immune responses and achieve significant antitumor effects. To address these challenges, we developed a dual-modality immune nano-activator by coordinating manganese ions with quercetin. This strategy was designed to enhance the cGAS-STING pathway activation and elicit the immunogenic cell death, thereby strengthening the antitumor immune response. The engineered nano-activator demonstrated superior tumor-targeting ability and efficient cellular internalization. Upon exposure to near-infrared irradiation, the system harnessed photothermal effects to induce apoptosis in tumor cells while simultaneously accelerating the release of manganese ions and quercetin. The released manganese ions facilitated the generation of reactive oxygen species, which in conjunction with quercetin-induced apoptosis, amplified photothermal-induced DNA damage. This DNA damage further promoted the release of cytosolic DNA, which in turn activated the cGAS-STING pathway, thereby intensifying immune activation. Notably, the nano-activator also triggered immunogenic cell death, which synergized with the cGAS-STING activation to promote dendritic cell maturation and activate antigen-specific T-cell, significantly enhancing the immune response against the tumor. Both in vitro and in vivo studies confirmed that this nano-activator effectively inhibited tumor growth, with particularly pronounced effects when combined with anti-CTLA-4 antibodies.

A Biocompatible NMOF-Based Drug Delivery System Designed for the Sustained and Controlled Release via pH-Responsive Poorly Soluble Drug 5-Fluorouracil

Cancer is among the most challenging diseases to manage, affecting millions of lives today. Numerous treatment approaches have been employed to combat cancer, each with its own limitations. One approach involves using anticancer medications that, regrettably, come with significant side effects. One reason for these issues is the lack of specificity in anticancer drugs, which can harm healthy tissues alongside targeted cancer cells. In this research, our goal is to minimize side effects and enhance drug effectiveness through advanced drug delivery techniques. The metal-organic framework (MOF) was swiftly created at the nanoscale using solvothermal synthesis. The NMOF-74 particles measure is nanometric in size and have a surface area of 950 m2 g-1. After the introduction of 5-fluorouracil, a coating of poly(acrylic acid) polymer was applied to the nanocarrier. The biocompatible nanocarrier demonstrated a strong ability to absorb the drug. The bioresorbable nanocarrier gradually and evenly released 97.9% of the drug in the simulated environment. This indicates that 5-FLU/NMOF-74 released the drug in a controlled and pH-responsive manner. The robustness of the compatible nanocarrier was tested across various pH levels and was found to remain stable at pH 1.2 for up to 72 h. The toxicity evaluation performed over a 24 h period on the MCF-7 cell line at various concentrations demonstrates that the compatible nanocarrier performs significantly better than the free drug regarding its impact on breast cancer cells.

In situ growth of defective ZIF-8 on TEMPO-oxidized cellulose nanofibrils for rapid response release of curcumin in food preservation

Uncontrolled release of active agents in active packaging reduces antimicrobial efficacy, hindering the effective protection of perishable products from microbial infection. Herein, a novel defective engineering was proposed to design defective and hollow ZIF-8 structures grown on TEMPO oxidized cellulose nanofibrils (TOCNFs) and use them as fast-reacting nanocarriers for loading and controlled release curcumin (Cur) in sodium alginate (SA) active packaging systems (CZT-Cur-SA). By employing stable chelation between tannic acid (TA) and ZIF-8 zinc ions, the connections between zinc ions and imidazole ligands were severed to form a loose and hollow structure, which facilitates the rapid reaction and release of active ingredients triggered by pH changes in the microenvironment. Kinetic tests showed CZT-Cur-SA films released 65.68 % of Cur at pH 6.0 within 24 h, compared to 28.26 % at pH 7.0. These films demonstrated exhibited excellent mechanical properties, antioxidation capacity (82.59 %), reinforced moisture (0.51 × 10-10 g m-1 s-1 Pa-1) and satisfied antimicrobial effects on E. coli (1.69 %) and S. aureus (0.88 %). The optimized CZT-Cur-SA film extended strawberry shelf life to at least 7 days under ambient conditions. Our findings introduce a promising approach to designing responsive, biodegradable active packaging for enhanced food safety.

Bifunctional mesoporous HMUiO-66-NH2 nanoparticles for bone remodeling and ROS scavenging in periodontitis therapy

Periodontal bone defects represent an irreversible consequence of periodontitis associated with reactive oxygen species (ROS). However, indiscriminate removal of ROS proves to be counterproductive for tissue repair and insufficient for addressing existing bone defects. In the treatment of periodontitis, it is crucial to rationally alleviate local ROS while simultaneously promoting bone regeneration. In this study, Zr-based large-pore hierarchical mesoporous metal-organic framework (MOF) nanoparticles (NPs) HMUiO-66-NH2 were successfully proposed as bifunctional nanomaterials for bone regeneration and ROS scavenging in periodontitis therapy. HMUiO-66-NH2 NPs demonstrated outstanding biocompatibility both in vitro and in vivo. Significantly, these NPs enhanced the osteogenic differentiation of bone mesenchymal stem cells (BMSCs) under normal and high ROS conditions, upregulating osteogenic gene expression and mitigating oxidative stress. Furthermore, in vivo imaging revealed a gradual degradation of HMUiO-66-NH2 NPs in periodontal tissues. Local injection of HMUiO-66-NH2 effectively reduced bone defects and ROS levels in periodontitis-induced C57BL/6 mice. RNA sequencing highlighted that differentially expressed genes (DEGs) are predominantly involved in bone tissue development, with notable upregulation in Wnt and TGF-β signaling pathways. In conclusion, HMUiO-66-NH2 exhibits dual functionality in alleviating oxidative stress and promoting bone repair, positioning it as an effective strategy against bone resorption in oxidative stress-related periodontitis.

Lipid/ZIF-8 Biocomposites Based on Liposomes or Vesicles: In Situ Formation, and Preliminary Evaluation as Delivery Vehicles for Hydrophobic Drugs

Integrating lipid self-assemblies with metal-organic frameworks (MOFs) creates biocomposites ideal for encapsulation, protection, and delivery of functional species. This can be achieved using preformed MOFs or through in situ MOF formation. Herein, the one-pot formation of ZIF-8 MOF particles in the presence of two lipid self-assemblies (vesicles or liposomes) is reported, generating two types of hybrid lipid/ZIF-8 biocomposites. Each lipid assembly can be used to encapsulate hydrophobic actives into the hybrid lipid/ZIF-8 biocomposites, demonstrated with Nile Red and Astaxanthin (ATX) as representative cargo. In vitro digestion of ATX-loaded hybrid lipid/ZIF-8 particles in simulated intestinal fluid (SIF) shows distinct release kinetics: liposome-based particles offer a more sustained release compared to vesicle-based biocomposites. Intriguingly, in various media (water, simulated gastric fluid, bicarbonate, and SIF), the sodalite ZIF-8 topology in liposome-based lipid/ZIF-8 particles undergoes a crystalline phase transition to the denser, more-stable phase ZIF-C. This phase transition, along with a deeper internalization of ATX in liposome-based particles, accounts for the differences in release kinetics. In summary, the study provides valuable insights for the synthesis of hybrid lipid/ZIF-8 biocomposites, the encapsulation of hydrophobic molecules, the importance of investigating potential crystalline phase transitions of MOFs in different media, and their potential as drug delivery vehicles.

Dual-functional co-crystal of streptavidin and ssDNA: electrostatic assembly with positively charged peptide tags

We have achieved a novel co-crystal in which the dual functions of the protein and single-stranded DNA are maintained by introducing a charged peptide tag at the C-terminus of the protein. The functionalities allowed the co-crystals to be modified with high selectivity. Additionally, we have confirmed that energy transfer occurs between the two molecules modified within the co-crystal. Therefore, this co-crystal has the potential as a novel biomaterial applicable to biosensors.

Hybrid Nanoplatforms Based on Photosensitizers and Metal/Covalent Organic Frameworks for Improved Cancer Synergistic Treatment Nano-Delivery Systems

Researchers have extensively investigated photosensitizer (PS) derivatives for various applications due to their superior photophysical and electrochemical properties. However, inherent problems, such as instability and self-quenching under physiological conditions, limit their biological applications. Metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) represent two relatively new material types. These materials have high surface areas and permanent porosity, and they show a tremendous deal of potential for applications like these. This review summarizes key synthesis processes and highlights recent advancements in integrating PS-based COF and MOF nanocarriers for biomedical applications while addressing potential obstacles and prospects.

Nanoscale Metal-Organic Frameworks for the Co-Delivery of Cycloxaprid and Pooled siRNAs to Enhance Control Efficacy in Diaphorina citri

RNA pesticides have emerged as a promising alternative to conventional chemical pesticides due to their high specificity and minimal environmental impact. However, the instability of RNA molecules in the environment and the challenges associated with their effective delivery to target pests limit their broader application. This study addresses these challenges by developing a dual delivery system using chitosan (CS) and Metal-Organic Frameworks (MOFs) to enhance the delivery and efficacy of double-stranded RNA (dsRNA) and cycloxaprid against Diaphorina citri, a vector of citrus greening disease. The CS-MOF nanoparticles were synthesized and characterized using scanning electron microscopy (SEM) and dynamic light scattering (DLS). Insect bioassays demonstrated that the codelivery system significantly improved insecticidal activity, achieving over 80% mortality in D. citri within 2 days. The results indicate that the encapsulation of dsRNA within MOFs enhances its stability, while the controlled release properties of the nanoparticles improve the efficacy of cycloxaprid. This novel approach shows great potential in overcoming the limitations of RNA pesticides and offers a sustainable solution for pest management in agriculture. Future research should optimize the delivery system, conduct field trials, and explore its applicability to other agricultural pests.

Transcriptomic modifications across the genome and potential hazards of pulmonary fibrosis caused by metal-organic frameworks

Metal-Organic Frameworks (MOFs) have shown great promise in environmental protection, owing to their exceptional properties including ultrahigh surface area and porosity, tunable pore size, and easy chemical functionalization. However, emerging evidence from experimental studies indicates that MOFs have side effects on human health due to metal ions doping, resulting in excessive reactive oxygen species (ROS) production, pro-inflammatory responses, and liver fibrosis. In this study, we investigated the impact of MOF-199 on human bronchial epithelial (HBE) cells by using transcriptome sequencing analysis. The results indicated that the stimulation of MOF-199 enhanced ROS generation, upregulated cytoplasmic Ca2+ levels, then activated the Grb2/SOS/Ras/Raf pathway, induced cell apoptosis, and ultimately resulted in lung fibroblasts through TGF-β secretion. The results were validated in vitro and in vivo. Therefore, it is necessary to carefully evaluate the nanosafety of MOF-199 in environment treatments.

Drug Delivery Systems Based on Metal-Organic Frameworks for Tumor Immunotherapy

Metal-organic frameworks (MOFs) are a class of inorganic-organic hybrid nanoparticles formed by the coordination of metal ions/clusters and organic ligands. Due to their high porosities, large surface areas, adjustable structures, and responsiveness to light/sound, etc., MOFs have shown great clinical potential in the field of tumor therapy. Tumor immunotherapy exerts antitumor effects through reshaping tumor immune microenvironment, showing significant preclinical and clinical advantages. Based on the mechanisms of immunity activation, the tumor immunotherapy agents can be divided into chemotherapeutic agents, immunomodulators, enzymes, tumor vaccines and oligonucleotide drugs, etc. Herein, we review the MOFs-based drug delivery systems for tumor immunotherapy. The classification of MOFs, followed by their antitumor immunity activation mechanisms, are first introduced. Drug delivery systems based on MOFs with different immunotherapy agents are also summarized, especially the synergetic immunity activation mechanisms triggered by MOFs and their loadings. Furthermore, the merits and drawbacks of MOFs and the potential strategies for MOFs to promote their clinical applications are discussed.

Size effect of ZIF-8 based nanocarrier pesticide delivery system on targeted release and insecticidal activity

BACKGROUND

Traditional chemical pesticides are easily lost by surface runoff and only small quantities reach the target, thus causing serious environmental pollution. In this work, dinotefuran@zeolitic imidazolate framework-8@polydopamine@zein (DNF@ZIF-8@PDA@zein), was constructed to deliver DNF with pH and enzyme double response of release, thereby achieving targeted release and efficient long-term pest control.

RESULTS

DNF@ZIF-8@PDA@zein was synthesized with three hydrated diameters (249.73 ± 9.99 nm, 142.94 ± 5.63 nm and 75.16 ± 4.66 nm, respectively). The release of DNF from DNF@ZIF-8@PDA@zein after 28 h was significantly higher at pH 5.0 (89.22 ± 7.18%) compared to that at pH 8 (81.8 ± 6.11%). Protease-assisted release of DNF was notably higher than that without protease (pH 5: 89.22 ± 5.55% versus 27.19 ± 3.22%; pH 8: 81.8 ± 6.11% versus 25.39 ± 3.87%). The stimuli-responsive release of DNF from DNF@ZIF-8@PDA@zein increased with decreased particle size due to increased pore size, reduced binding forces (i.e., weaker π-π stacking, hydrogen bonding, and Zn-N covalent bonding), and the shortening of diffusion path, leading to faster disintegration and drug release. Additionally, the anti-photolysis ability of DNF@ZIF-8@PDA@zein was 3.2 times that of pure DNF. The insecticidal activity improved with smaller nanoparticles due to higher drug release rate and greater inhibition of detoxification enzyme activity by more zinc ion (Zn2+) dissolution.

CONCLUSION

The pH and enzyme dual-responsive release as well as insecticidal activity of DNF@ZIF-8@PDA@zein increase with decreased nanoparticle size, showing effective pest management in long-term and potential application prospects in sustainable agriculture. © 2024 Society of Chemical Industry.

Metal-phenolic network biointerface-mediated cell regulation for bone tissue regeneration

Bone tissue regeneration presents a significant challenge in clinical treatment due to inadequate coordination between implant materials and reparative cells at the biomaterial-bone interfaces. This gap underscores the necessity of enhancing interaction modulation between cells and biomaterials, which is a crucial focus in bone tissue engineering. Metal-polyphenolic networks (MPN) are novel inorganic-organic hybrid complexes that are formed through coordination interactions between phenolic ligands and metal ions. These networks provide a multifunctional platform for biomedical applications, with the potential for tailored design and modifications. Despite advances in understanding MPN and their role in bone tissue regeneration, a comprehensive overview of the related mechanisms is lacking. Here, we address this gap by focusing on MPN biointerface-mediated cellular regulatory mechanisms during bone regeneration. We begin by reviewing the natural healing processes of bone defects, followed by a detailed examination of MPN, including their constituents and distinctive characteristics. We then explore the regulatory influence of MPN biointerfaces on key cellular activities during bone regeneration. Additionally, we illustrate their primary applications in addressing inflammatory bone loss, regenerating critical-size bone defects, and enhancing implant-bone integration. In conclusion, this review elucidates how MPN-based interfaces facilitate effective bone tissue regeneration, advancing our understanding of material interface-mediated cellular control and the broader field of tissue engineering.

Inhalable Metal-Organic Frameworks: A Promising Delivery Platform for Pulmonary Diseases Treatment

Inhalation delivery, offering a direct pathway for administering drugs to the lungs in the form of dry powders or aerosols, stands out as an optimal approach for the localized treatment of pulmonary diseases. However, the intricate anatomical architecture of the lung often poses challenges in maintaining effective drug concentrations within the lungs over extended periods. This highlights the pressing need to develop rational inhalable drug delivery systems that can improve treatment outcomes for respiratory diseases. Metal-organic frameworks (MOFs) assembled from inorganic metal ions and organic ligands, characterized by customizable porous architecture and chemical composition, modifiable porosity, vast surface area, straightforward surface modification, and adjustable biocompatibility, have garnered extensive attention in the biomedical sphere. The introduction of MOFs into inhalation therapy represents a promising avenue to navigate past the hurdles associated with traditional inhalation methods. Therefore, this review summarizes the characteristics of inhalation delivery together with the latest advances, challenges, and opportunities in utilizing inhalable MOFs for treating lung diseases and discusses prospects in this field alongside the potential pathways for translating this strategy into clinic.

An analytical review of the therapeutic application of recent trends in MIL-based delivery systems in cancer therapy

MILs (Materials Institute Lavoisier), as nanocarriers based on metal-organic frameworks (MOFs), are one of the most advanced drug delivery vehicles that are now a major part of cancer treatment research. This review article highlights the key features and components of MIL nanocarriers for the development and improvement of these nanocarriers for drug delivery. Surface coatings are one of the key components of MIL nanocarriers, which play the role of stabilizing the nanocarrier, pH-dependent drug release, increasing the half-life of the drug, and targeting the carrier. MIL nanocarriers have been synthesized mainly by thermal and hydrothermal methods due to their single-step nature and the ability to produce individual crystals with tunable sizes. According to the data available in the literature, MIL-53 and MIL-101 are the best MILs for drug delivery. These MILs have a high ability to release drugs under acidic conditions, indicating their high efficiency compared to other MILs. In addition to drugs, these nanocarriers can also carry fluorescent, photothermal, and photodynamic agents. These agents allow the MIL nanocarriers to benefit from the therapeutic potential of photothermal and photodynamic agents in addition to the therapeutic capacity of the drug. Furthermore, the fluorescent active ingredient gives these nanocarriers a further tracking capability in addition to the inherent tracking capability of MRI. Therefore, MIL nanocarriers as theranostic carriers have the potential to revolutionize both drug delivery and imaging.

Improving the use of CRISPR/Cas9 gene editing machinery as a cancer therapeutic tool with the help of nanomedicine

CRISPR-Cas9 (clustered regularly interspaced short palindromic repeats-associated protein 9) has revolutionized gene editing tools and paved the way for innovations in medical research for disease diagnosis and treatment. However, better specificity and efficient delivery of this gene machinery make it challenging to successfully edit genes for treating various diseases. This is mainly due to cellular barriers, instability in biological environments, and various off-target effects that prohibit safe and efficient delivery under in vivo conditions. This review examines several delivery modes [plasmid, mRNA, RNP (ribonucleoprotein)] and methods for the CRISPR-Cas9 system delivery, focusing on its potential applications in cancer therapy. Biocompatibility and cytotoxicity are crucial factors determining their safe and effective use. Various nanomaterials have been reviewed for their biocompatibility, limitations, and challenges in treating cancer. Among the reviewed nanoparticles, lipid nanoparticles (LNPs) stand out for their biocompatibility due to their biomimetic lipid bilayer that effectively delivers CRISPR/Cas9 cargoes while reducing toxicity. We discuss challenges in in vivo delivery and associated findings such as encapsulation, target delivery, controlled release, and endosomal escape. Future directions involve addressing limitations and adapting CRISPR-Cas9 for clinical trials, ensuring its safe and effective use.

Solution Processable Metal-Organic Frameworks: Synthesis Strategy and Applications

Metal-organic frameworks (MOFs), constructed by inorganic secondary building units with organic linkers via reticular chemistry, inherently suffer from poor solution processability due to their insoluble nature, resulting from their extensive crystalline networks and structural rigidity. The ubiquitous occurrence of precipitation and agglomeration of MOFs upon formation poses a significant obstacle to the scale-up production of MOF-based monolith, aerogels, membranes, and electronic devices, thus restricting their practical applications in various scenarios. To address the previously mentioned challenge, significant strides have been achieved over the past decade in the development of various strategies aimed at preparing solution-processable MOF systems. In this review, the latest advance in the synthetic strategies for the construction of solution-processable MOFs, including direct dispersion in ionic liquids, surface modification, controllable calcination, and bottom-up synthesis, is comprehensively summarized. The respective advantages and disadvantages of each method are discussed. Additionally, the intriguing applications of solution-processable MOF systems in the fields of liquid adsorbent, molecular capture, sensing, and separation are systematically discussed. Finally, the challenges and opportunities about the continued advancement of solution-processable MOFs and their potential applications are outlooked.

Tailored polysaccharide entrapping metal-organic framework for RNAi therapeutics and diagnostics in atherosclerosis

Metal-organic frameworks (MOFs) hold promise as theranostic carriers for atherosclerosis. However, to further advance their therapeutic effects with higher complexity and functionality, integrating multiple components with complex synthesis procedures are usually involved. Here, we reported a facile and general strategy to prepare multifunctional anti-atherosclerosis theranostic platform in a single-step manner. A custom-designed multifunctional polymer, poly(butyl methacrylate-co-methacrylic acid) branched phosphorylated β-glucan (PBMMA-PG), can effectively entrap different MOFs via coordination, simultaneously endow the MOF with enhanced stability, lesional macrophages selectivity and enhanced endosome escape. Sequential ex situ characterization and computational studies elaborated the potential mechanism. This facile post-synthetic modification granted the administered nanoparticles atherosclerotic tropism by targeting Dectin-1+ macrophages, enhancing in situ MR signal intensity by 72 %. Delivery of siNLRP3 effectively mitigated NLRP3 inflammasomes activation, resulting a 43 % reduction of plaque area. Overall, the current study highlights a simple and general approach for fabricating a MOF-based theranostic platform towards atherosclerosis conditioning, which may also expand to other indications targeting the lesional macrophages.

Deep Learning for the Accurate Prediction of Triggered Drug Delivery

The need to mitigate the adverse effects of chemotherapy has driven the exploration of innovative drug delivery approaches. One emerging trend in cancer treatment is the utilization of Drug Delivery Systems (DDSs), facilitated by nanotechnology. Nanoparticles, ranging from 1 nm to 1000 nm, act as carriers for chemotherapeutic agents, enabling precise drug delivery. The triggered release of these agents is vital for advancing this novel drug delivery system. Our research investigated this multifaceted delivery capability using liposomes and metal organic frameworks as nanocarriers and utilizing all three targeting techniques: passive, active, and triggered. Liposomes are modified using targeting ligands to render them more targeted toward certain cancers. Moieties are conjugated to the surfaces of these nanocarriers to allow for their binding to receptors overexpressed on cancer cells, thus increasing the accumulation of the agent at the tumor site. A novel class of nanocarriers, namely metal organic frameworks, has emerged, showing promise in cancer treatment. Triggering techniques (both intrinsic and extrinsic) can be used to release therapeutic agents from nanoparticles, thus enhancing the efficacy of drug delivery. In this study, we develop a predictive model combining experimental measurements with deep learning techniques. The model accurately predicts drug release from liposomes and MOFs under various conditions, including low- and high-frequency ultrasound (extrinsic triggering), microwave exposure (extrinsic triggering), ultraviolet light exposure (extrinsic triggering), and different pH levels (intrinsic triggering). The deep learning-based predictions significantly outperform linear predictions, proving the utility of advanced computational methods in drug delivery. Our findings demonstrate the potential of these nanocarriers and highlight the efficacy of deep learning models in predicting drug release behavior, paving the way for enhanced cancer treatment strategies.

Dynamic pH‐Responsive Release and Biological Impact of In Situ Quercetin‐Modified MIL‐101(Fe)‐NH2

A successful investigation was conducted on the in situ modification of MIL‐101(Fe)‐NH2 with quercetin and its controlled release under various pH conditions. MIL‐101(Fe)‐NH2 was synthesized using an electrochemical method at room temperature (15 volts, 30 min). The formation of the material was confirmed through comprehensive analyses, including PXRD, FTIR, and TGA. Nitrogen sorption isotherm measurements revealed that Qu@MIL‐101(Fe)‐NH2 exhibited a smaller surface area compared to MIL‐101(Fe)‐NH2, with both materials classified as mesoporous. Transmission electron microscopy (TEM) clearly depicted the materials’ octahedral microspindle morphology. The cumulative percent release (CPR) of quercetin from Qu@MIL‐101(Fe)‐NH2 over 72 h was determined to be 53.45 % at pH 1.2, 19.48 % at pH 4.8, and 5.87 % at pH 7.4. Notably, quercetin release in the acidic microenvironment representative of cancer cells (pH 4.8) was nearly four times higher than under physiological conditions (pH 7.4). Kinetic release studies indicated that quercetin release from Qu@MIL‐101(Fe)‐NH2 followed the Ritger‐Peppas kinetic model, suggesting non‐Fickian diffusion. The MIL‐101(Fe)‐NH2 nanocarriers, with in situ‐loaded quercetin, demonstrated promising potential for pH‐triggered drug release. Additionally, the safety of MIL‐101(Fe)‐NH2 in biological models and the anticancer efficacy of quercetin were evaluated in vitro using two liver cancer cell lines.

Nanocarriers in glioblastoma treatment: a neuroimmunological perspective

Glioblastoma multiforme (GBM) is the most fatal brain tumor with a poor prognosis with current treatments, mainly because of intrinsic resistance processes. GBM is also referred to as grade 4 astrocytoma, that makes up about 15.4 % of brain cancers globally as well as 60-75 % of astrocytoma. The most prevalent therapeutic choices for GBM comprise surgery in combination with radiotherapy and chemotherapy, providing patients with an average survival of 6-14 months. Nanocarriers provide various benefits such as enhanced drug solubility, biocompatibility, targeted activity, as well as minimized side effects. In addition, GBM treatment comes with several challenges such as the presence of the blood-brain barrier (BBB), blood-brain tumor barrier (BBTB), overexpressed efflux pumps, infiltration, invasion, drug resistance, as well as immune escape due to tumor microenvironment (TME) and cancer stem cells (CSC). Recent research has focused on nanocarriers due to their ability to self-assemble, improve bioavailability, provide controlled release, and penetrate the BBB. These nano-based components could potentially enhance drug accumulation in brain tumor tissues and reduce systemic toxicity, making them a compelling solution for GBM therapy. This review captures the complexities associated with multi-functional nano drug delivery systems (NDDS) in crossing the blood-brain barrier (BBB) and targeting cancer cells. In addition, it presents a succinct overview of various types of targeted multi-functional nano drug delivery system (NDDS) which has exhibited promising value for improving drug delivery to the brain.

A Zr-based metal-organic framework drug release system with long-lasting antibacterial behavior for accelerating wound healing

Although various antibacterial strategies have been developed, antibiotic chemotherapy remains the primary clinical treatment for bacterial infections. To address the limitations associated with the traditional antibiotic therapy, like burst drug release, rapid drug clearance, and the emergence of drug resistance, it is highly desirable to develop drug release systems that can realize controlled and sustained drug release to enhance the therapeutic efficacy. Herein, we present a novel drug release system, CIP@SU-102, which shows superior and long-lasting antibacterial activity. CIP@SU-102 was readily fabricated by the encapsulation of ciprofloxacin (CIP), a cationic broad-spectrum antibiotic, into an anionic Zr-based metal-organic framework SU-102 through ion-exchange. Notably, the loading capacity and efficiency of CIP were impressively high, reaching 33.3% and 66.8%, respectively. In vitro assays demonstrated that CIP@SU-102 has superior and prolonged antimicrobial activity against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria, including the methicillin-resistant Staphylococcus aureus (MRSA). Remarkably, CIP@SU-102 could retain its antibacterial efficacy even after continuous drug release for 20 days. In vivo assays verified that CIP@SU-102 could significantly accelerate infected wound healing because of its sustained drug release properties. Due to the low cost and biocompatibility of SU-102 as well as the affordability of ciprofloxacin, CIP@SU-102 is a very promising antibacterial agent for long-lasting bacterial disinfection and boosting infected wound healing in actual clinical applications. This work highlights the potential of the metal-organic framework-based drug release systems for sustained antimicrobial therapy.

A low-toxicity uranyl-selective-binding linear pentapeptide sequence as a potential uranium decorporation agent

Searching for highly selective, efficient, and low-toxicity chelating agents is central to resolving uranium contamination in vivo. Peptides composed of amino acids exhibit very low toxicity for accumulation in the human body and have been proven effective in chelating actinides within the human body. Herein, we report a rationally designed short phosphorylated peptide sequence PP-B, which exhibits high affinity and selectivity for uranyl compared to other trace elements present in the body (such as Na+, K+, Ca2+, Co2+, Fe2+, Fe3+, Mg2+, Mn2+, Zn2+). The association constant for the peptide-uranyl complex is calculated to be 7.3 ×105 M-1. The result of DFT calculation shows that the phosphate group binds strongly to the UO2 2+ center, potentially accounting for the peptide's strong affinity towards UO2 2+. The results of in vivo uranyl decorporation assays reveal that PP-B has a much lower toxicity and a much higher decorporation efficiency than that of the clinically approved DTPA. These findings render PP-B a promising candidate for utilization as a novel decorporation agent.

Nanotechnology-Based Approaches for the Management of Diabetes Mellitus: An Innovative Solution to Long-Lasting Challenges in Antidiabetic Drug Delivery

Diabetes is a widespread metabolic illness. Mismanagement of diabetes can lead to severe complications that tremendously impact patients' quality of life. The assimilation of nanotechnology in diabetes care holds the potential to revolutionize treatment paradigms, improve patient outcomes, and reduce the economic burden associated with this pervasive disease. This manuscript explores the multifaceted utilization of nanomaterials in diabetes care, emphasizing the unique features of nano-based medication delivery methods and smart drug delivery mechanisms. Additionally, this paper talks about research on nanocarrier-integrated oral, transdermal, and inhalable insulin delivery; dendrimer- and nanocarrier-coupled antisense oligonucleotide-driven gene therapy; the implementation of gold nanoparticles and quantum dots for glucose surveillance; and nucleic acid therapies. There are certain restrictions when using medication delivery methods that are commonly available to handle diabetes. In order to increase efficacy and safety, the rapidly developing science of nanotechnology is also being explored and employed in medical biology. Nanomaterials like liposomes, dendrimers, niosomes, polymeric and metallic nanocarriers, and solid lipid nanoparticles are among the nanocarriers that have been developed for better delivery of various oral hypoglycemic agents in comparison to conventional therapies. These nanocarriers provide great control over elevated blood glucose levels, making them one of the most intriguing and promising technologies available today. Furthermore, adding additional ligands to nanocarriers allows for more focused distribution while protecting the encapsulated hypoglycemic drugs.

Advances in nanotechnology-based approaches for the treatment of head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC), one of the most common types of cancers occurring in the head and neck region, is often associated with high mortality rates due to its invasiveness and morbidity. The mainstream treatment methods in clinical settings, including surgery, chemotherapy, and radiotherapy, may cause poor overall survival rate and prognosis, with issues such as drug resistance, damage to adjacent healthy tissues, and potential recurrences. Other treatment approaches such as immunotherapy, photodynamic therapy (PDT), and photothermal therapy (PPT) also suffer from inefficient tumor targeting and suboptimal therapeutic outcomes. Early detection is vital for HNSCC patients, but it is always limited by insensitivity and confusing clinical manifestations. Hence, it is highly desirable to develop optimized therapeutic and diagnostic strategies. With the boom in nanomaterials, nanotechnology-conducted HNSCC therapy has attracted widespread attention. Nanoparticles (NPs) are distinguished by their unique morphology and superior physicochemical property, and some can exhibit direct antitumor activity, while others serve as promising candidates for drug delivery. In addition, NPs offer the potential for structural modification for drug delivery and tumor targeting, enabling specific delivery to tumor cells through conjugation with biomarker ligands and improving cargo biocompatibility. This work reviews current therapies and diagnosis methods for HNSCC, highlights the characteristics of the major NPs, surveys their uses and advantages in the treatment of HNSCC, and discusses the obstacles and prospects in clinical applications, aiming to enlighten future research directions for nanotechnology-based therapy for HNSCC.

MIL-101(Fe)@ceramic-monolith for arsenic removal in aqueous solutions

In this work, we present the preparation of a hybrid material constituted by a Metal-Organic Framework (type MIL-101(Fe)) and a natural clay ceramic monolith (NCCM), the materials were successfully assembled through an in-situ hydrothermal method. The composites were characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), N2 adsorption-desorption isotherms at 77 K and CO2 adsorption at 273 K; these techniques confirmed the obtaining of the hybrid material and, in addition, through studies before and after adsorption mechanisms involved were identified. Then, the As(V) adsorption capacity of the materials was evaluated using an aqueous arsenic solution; from which high adsorption capacities of up to 268 mg g- 1 and 61.5 mg g- 1, respectively. In addition, kinetic and equilibrium studies of As(V) adsorption were carried out. Finally, the potential capacities of the hybrid material consisting of Al2O3, AlO6-SiO4 and Fe3O4 for the adsorption of H3AsO4, were studied through density functional theory calculations.

Reticular Chemistry for Enhancing Bioentity Stability and Functional Performance

Addressing the fragility of bioentities that results in instability and compromised performance during storage and applications, reticular chemistry, specifically through metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), offers versatile platforms for stabilization and enhancement of bioentities. These highly porous frameworks facilitate efficient loading and mass transfer, offer confined environments and selective permeability for stabilization and protection, and enable finely tunable biointerfacial interactions and microenvironments for function optimization, significantly broadening the applications of various bioentities, including enzymes, nucleic acids, cells, etc. This Perspective outlines strategies for integrating bioentities with reticular frameworks, highlighting new design ideas for existing issues within these strategies. It emphasizes the crucial roles of these frameworks for bioentities in enhancing stability, boosting activity, imparting non-native functions, and synergizing bioentity systems. Concluding with a discussion of the challenges and prospects in the design, characterization, and practical applications of these biocomposites, this Perspective aims to inspire further development of high-performance biocomposites in this promising field.

Biofabrication of bimetallic selenium@zinc nanoparticles using Champia parvula aqueous extract: Investigation of anticancer activity and its apoptosis induction

Selenium@zinc nanoparticles, or Se@Zn NPs, are extensively employed in various environmental, industrial and biological domains. However, the biological potential of Se@Zn NPs has not been thoroughly investigated. This study focused on fabricating Se@Zn NPs from algae using an aqueous extract of Champia parvula seaweed. Analytical techniques were used to describe the successfully synthesized Se@Zn NPs. In addition, a biological function analysis of the Se@Zn NPs was conducted. The Ultraviolet-visible spectroscopy (UV-vis) spectrum showed a specific absorbance peak for the Se@Zn NPs at 350-400 nm. The biomolecules involved in forming Se@Zn NPs were identified by their potential functional groups, as revealed by Fourier transform infrared spectroscopy (FTIR). By scanning electron microscopy (SEM) and transmission electron microscopy (TEM), Se@Zn NPs were shown to be spherical and to have a diameter range of 100-200 nm. NPs with a crystallite diameter of 54.8 nm and chemical compositions of zinc and selenium (1:1.5 ratio) were revealed by X-ray diffraction analysis (XRD) and energy dispersive x-ray spectroscopy (EDS). IC50 values were determined for the anticancer activity against A549, MCF-7 and HeLa cells. Cell morphological changes in fluorescence microscopy and apoptosis mechanisms by flow cytometry analysis were investigated, which show that Se@Zn NPs induced apoptosis in various cancer cells. DNA fragmentation and ROS levels were studied by fluorescence microscopy. In conclusion, conditions required for therapeutic and preventative applications may be met by the green synthesis of Se@Zn NPs.

pH-Responsive Metal-Organic Framework for Targeted Delivery of Fungicide, Release Behavior, and Sustainable Plant Protection

A smart and environmentally friendly pesticide system was developed that could respond to environmental stimuli while mitigating environmental risks. In this study, thiabendazole (Thi), an effective fungicide, was loaded onto zeolitic imidazolate framework-8 (ZIF-8) using the impregnation method to fabricate a pH-responsive nano hybrid delivery system (Thi@ZIF-8). The results demonstrated that Thi@ZIF-8 had a rhombic dodecahedral morphology and a loading capacity of approximately 25%. Notably, the amount of Thi released from Thi@ZIF-8 at a pH of 5.0 reached 79.54%, which was higher than that at pH 7.0 and 9.0, for 251 h. Such pH-responsive release characteristics of Thi@ZIF-8 were probably related to the pH-dependent structure stability of ZIF-8. The release mechanism of Thi@ZIF-8 conformed to non-Fickian diffusion. Additionally, Thi@ZIF-8 showed a higher control efficacy against B. cinerea compared with Thi alone. Importantly, the ZIF-8 carrier could effectively reduce the leaching loss of Thi in soil and showed no negative effects on the three varieties of tomato seedlings, implying good biocompatibility. This work provides a novel and eco-friendly approach to control B. cinerea effectively that has great potential in modern sustainable agriculture.

Spleen Targeting Nucleic Acid Delivery Vector Based on Metal-Organic Frameworks

Nucleic acids have attracted increasing attention as drugs due to their fascinating advantages, such as long-term efficacy and ease of preparation compared to proteins. The nucleic acid therapy relies heavily on delivery vectors, which can prevent the degradation of nucleic acids while assisting them in cellular internalization. However, commonly used nonviral vector liposomes easily accumulate in the liver, which can limit their application in extrahepatic diseases. Herein, a potential spleen targeting vector for nucleic acids is developed based on the metal-organic frameworks. The plasmids are encapsulated inside the nanoscale zeolitic imidazolate framework (ZIF) via coprecipitation. The co-encapsulation of the cationic polymer poly(ether imide) (PEI) and the stabilizer polyvinylpyrrolidone (PVP) can significantly improve particle dispersion and stability. The prepared nanoparticles allow efficient transfection in vitro, mainly through clathrin-mediated and caveolae-mediated endocytosis. The biodistribution in mice shows that 46% of the nanoparticles accumulate in the spleen, which is much higher than that of the liposomes. The vector can successfully deliver plasmids to extrahepatic organs for protein synthesis and even induce an immune response. The elaborate ZIF-based nanoparticle may offer a new route for extrahepatic, especially spleen targeting delivery for the nucleic acids.

A novel PEG-mediated approach to entrap hemoglobin (Hb) within ZIF-8 nanoparticles: Balancing crystalline structure, Hb content and functionality

Hemoglobin (Hb)-based oxygen carriers are investigated as a potential alternative or supplement to regular blood transfusions, particularly in critical and life-threatening scenarios. These include situations like severe trauma in remote areas, battlefield conditions, instances where blood transfusion is not feasible due to compatibility concerns, or when patients decline transfusions based on religious beliefs. This study introduces a novel method utilizing poly(ethylene glycol) (PEG) to entrap Hb within ZIF-8 nanoparticles (i.e., Hb@ZIF-8 NPs). Through meticulous screening, we achieved Hb@ZIF-8 NPs with a record-high Hb concentration of 34 mg mL-1. These NPs, sized at 168 nm, displayed exceptional properties: a remarkable 95 % oxyhemoglobin content, excellent encapsulation efficiency of 85 %, and resistance to Hb oxidation into methemoglobin (metHb). The addition of PEG emerged as a crucial factor amplifying Hb entrapment within ZIF-8, especially at higher Hb concentrations, reaching an unprecedented 34 mg mL-1. Importantly, PEG exhibited a protective effect, preventing metHb conversion in Hb@ZIF-8 NPs at elevated Hb concentrations.

Fabricating oxygen self-supplying 3D printed bioactive hydrogel scaffold for augmented vascularized bone regeneration

Limited cells and factors, inadequate mechanical properties, and necrosis of defects center have hindered the wide clinical application of bone-tissue engineering scaffolds. Herein, we construct a self-oxygenated 3D printed bioactive hydrogel scaffold by integrating oxygen-generating nanoparticles and hybrid double network hydrogel structure. The hydrogel scaffold possesses the characteristics of extracellular matrix; Meanwhile, the fabricated hybrid double network structure by polyacrylamide and CaCl2-crosslinked sodium carboxymethylcellulose endows the hydrogel favorable compressive strength and 3D printability. Furthermore, the O2 generated by CaO2 nanoparticles encapsulated in ZIF-8 releases steadily and sustainably because of the well-developed microporous structure of ZIF-8, which can significantly promote cell viability and proliferation in vitro, as well as angiogenesis and osteogenic differentiation with the assistance of Zn2+. More significantly, the synergy of O2 and 3D printed pore structure can prevent necrosis of defects center and facilitate cell infiltration by providing cells the nutrients and space they need, which can further induce vascular network ingrowth and accelerate bone regeneration in all areas of the defect in vivo. Overall, this work provides a new avenue for preparing cell/factor-free bone-tissue engineered scaffolds that possess great potential for tissue regeneration and clinical alternative.

Biomedical Metal-Organic Framework Materials: Perspectives and Challenges

Metal-organic framework (MOF) materials are gaining significant interest in biomedical research, owing to their high porosity, crystallinity, and structural and compositional diversity. Their versatile hybrid organic/inorganic chemistry endows MOFs with the capacity to retain organic (drug) molecules, metals, and gases, to effectively channel electrons and photons, to survive harsh physiological conditions such as low pH, and even to protect sensitive biomolecules. Extensive preclinical research has been carried out with MOFs to treat several pathologies and, recently, their integration with other biomedical materials such as stents and implants has demonstrated promising performance in regenerative medicine. However, there remains a significant gap between MOF preclinical research and translation into clinically and societally relevant medicinal products. Here, we outline the intrinsic features of MOFs and discuss how these are suited to specific biomedical applications like detoxification, drug and gas delivery, or as (combination) therapy platforms. We furthermore describe relevant examples of how MOFs have been engineered and evaluated in different medical indications, including cancer, microbial, and inflammatory diseases. Finally, we critically examine the challenges facing their translation into the clinic, with the goal of establishing promising research directions and more realistic approaches that can bridge the translational gap of MOFs and MOF-containing (nano)materials.

Metal-organic frameworks in drug delivery: engineering versatile platforms for therapeutic applications

Recently, metal-organic frameworks (MOFs) have attracted much attention as versatile materials for drug delivery and personalized medicine. MOFs are porous structures made up of metal ions coupled with organic ligands. This review highlights the synthesis techniques used to design MOFs with specific features such as surface area and pore size, and the drug encapsulation within MOFs not only improves their stability and solubility but also allows for controlled release kinetics, which improves therapeutic efficacy and minimizes adverse effects. Furthermore, it discusses the challenges and potential advantages of MOF-based drug delivery, such as MOF stability, biocompatibility, and scale-up production. With further advancements in MOF synthesis, functionalization techniques, and understanding of their interactions using biological systems, MOFs can have significant promise for expanding the area of personalized medicine and improving patient outcomes.

MOF-Modified Microrollers for Bioimaging and Sustained Antibiotic Delivery

Central nervous system (CNS) infections caused by neurosurgery or intrathecal injection of contaminated cerebrospinal fluid are a common and difficult complication. Drug-delivery microrobots are among the latest solutions proposed for antibacterial applications. However, there is a lack of research into developing microrobots with the ability to sustain antibody delivery while can move efficiently in the CNS. Here, biocompatible antibacterial metal-organic framework (MOF)-modified microrollers (MMRs) to combat CNS infections are proposed. The MMRs are iron-based metal-organic framework (NH2-MIL-101(Fe)) modified for enhanced adsorption and Fe/Al coated for magnetic actuation and biocompatibility. The MMRs have demonstrated a faster and unhindered magnetically actuated motion on the uneven biological tissue surface in an organ-on-a-chip that mimicked the CNS compared to it on smooth surface. CFD results consistently align with the experimental findings. The MMRs can be loaded with rhodamine 6G for bioimaging, allowing them to be imaged through sections of the main human tissues by fluorescence microscopy, or tetracycline hydrochloride for antibiotic delivery, allowing them to inhibit the growth of Staphylococcus aureus biofilms by sustained release of antibiotics for 9 days. This study provides a strategy to integrate high-capacity adsorption material with magnetically actuated locomotion for long-term targeted antibacterial applications in biological environments.

Enhancing Two-Photon Excited Fluorescence of Metal-Organic Framework Single Crystals through Modulation of Inorganic Nodes

Regulation of the two-photon excited fluorescence (TPEF) emission intensity and wavelength of metal-organic framework (MOF) crystals with similar constitutions presents a significant challenge. In this study, two MOFs, Zn-BTPPA and Cd3-BTPPA, were constructed using tetrakis(1,1'-biphenyl-4-carboxylic acid)-1,4-benzenediamine (H4BTPPA) as the organic ligand and mononuclear Zn and trinuclear Cd3 inorganic nodes, respectively. The incorporation of H4BTPPA within the MOF structures enables effective TPEF emission in both Zn-BTPPA and Cd3-BTPPA. The TPEF results show that Zn-BTPPA and Cd3-BTPPA exhibited strong emissions at 523 and 463 nm, respectively, when excited with a 780 nm laser. Moreover, Zn-BTPPA and Cd3-BTPPA exhibited much higher two-photon absorption cross sections, approximately 4.9 and 5.2 times higher than that of the reported dinuclear MOF, Cd2-BTPPA, with a similar composition, respectively. With different inorganic nodes, the stacking of chromophores, π···π interactions, and ligand geometry were found to correlate with the enhanced TPEF in Cd3-BTPPA and the blue-shifted TPEF in Zn-BTPPA. This work serves as an inspiration for designing efficient TPEF MOF materials based on the structure-property relationship.

Porous titanium scaffolds modified with Zeolitic Imidazolate Framework (ZIF-8) with enhanced osteogenic activity for the prevention of implant-associated infections

In this study, zeolitic imidazolate framework 8 (ZIF-8) was coated on porous Ti6Al4V scaffolds, either bare or previously modified using hydroxyapatite (HA) or HA and gelatin (HAgel), via a growing single-step method in aqueous media using two contact times at 6 h and 24 h. The coated scaffolds termed ZIF-8@Ti, ZIF-8@HA/Ti, and ZIF-8@HAgel/Ti were characterized via scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), attenuated total reflectance-Fourier transform infrared (ATR-FTIR), and molecular plasma-atomic emission spectroscopy (MP-AES). In order to assess the cell proliferation rate, the cytocompatibility of the scaffolds was evaluated in primary osteoblasts (hOBs) using alamarBlue assay, while the osteoconductivity was analyzed in hOBs using a real-time approach, evaluating the expression of secreted phosphoprotein 1 (SPP1). Osteopontin, which is the protein encoded by this gene, represents the major non-collagenous bone protein that binds tightly to HA. The scaffolds were shown to be non-cytotoxic based on hOB proliferation at all time points of analysis (24 h and 72 h). In hOB cultures, the scaffolds induced the upregulation of SPP1 with different fold changes. Some selected scaffolds were assayed in vitro for their antibacterial potential against Staphylococcus epidermidis; the scaffolds coated with ZIF-8 crystals, regardless of the presence of HA and gelatin, strongly inhibited bacterial adhesion to the materials and reduced bacterial proliferation in the culture medium, demonstrating the suitable release of ZIF-8 in a bioactive form. These experiments suggest that the innovative scaffolds, tested herein, provide a good microenvironment for hOB adhesion, viability, and osteoconduction with effective prevention of S. epidermidis adhesion.