Metal-organic frameworks: A novel platform for combined advanced therapies

Metal-organic frameworks for biomedical applications: A review

Metal-organic frameworks (MOFs) are emergent materials in diverse prospective biomedical uses, owing to their inherent features such as adjustable pore dimension and volume, well-defined active sites, high surface area, and hybrid structures. The multifunctionality and unique chemical and biological characteristics of MOFs allow them as ideal platforms for sensing numerous emergent biomolecules with real-time monitoring towards the point-of-care applications. This review objects to deliver key insights on the topical developments of MOFs for biomedical applications. The rational design, preparation of stable MOF architectures, chemical and biological properties, biocompatibility, enzyme-mimicking materials, fabrication of biosensor platforms, and the exploration in diagnostic and therapeutic systems are compiled. The state-of-the-art, major challenges, and the imminent perspectives to improve the progressions convoluted outside the proof-of-concept, especially for biosensor platforms, imaging, and photodynamic therapy in biomedical research are also described. The present review may excite the interdisciplinary studies at the juncture of MOFs and biomedicine.

Nanoscaled metal-organic frameworks: charting a transformative path for cancer therapeutics and beyond

Through this inspirational note, we would like to highlight the potential of nanoscaled metal-organic frameworks within the biomedical field. The unique properties of these materials that make them promising candidates for new nanomedicines are assessed here as well as the progression reached so far for combinational cancer therapies and theranostic, along with its most recent advances in nanomedicine. Finally, the perspective and challenges of these materials within this field is discussed.

Bioactive Metal-Organic Frameworks as a Distinctive Platform to Diagnosis and Treat Vascular Diseases

Vascular diseases (VDs) pose the leading threat worldwide due to high morbidity and mortality. The detection of VDs is commonly dependent on individual signs, which limits the accuracy and timeliness of therapies, especially for asymptomatic patients in clinical management. Therefore, more effective early diagnosis and lesion-targeted treatments remain a pressing clinical need. Metal-organic frameworks (MOFs) are porous crystalline materials formed by the coordination of inorganic metal ions and organic ligands. Due to their unique high specific surface area, structural flexibility, and functional versatility, MOFs are recognized as highly promising candidates for diagnostic and therapeutic applications in the field of VDs. In this review, the potential of MOFs to act as biosensors, contrast agents, artificial nanozymes, and multifunctional therapeutic agents in the diagnosis and treatment of VDs from the clinical perspective, highlighting the integration between clinical methods with MOFs is generalized. At the same time, multidisciplinary cooperation from chemistry, physics, biology, and medicine to promote the substantial commercial transformation of MOFs in tackling VDs is called for.

Metal-Organic Frameworks: Unconventional Nanoweapons against COVID

The SARS-CoV-2 (COVID-19) pandemic outbreak led to enormous social and economic repercussions worldwide, felt even to this date, making the design of new therapies to combat fast-spreading viruses an imperative task. In the face of this, diverse cutting-edge nanotechnologies have risen as promising tools to treat infectious diseases such as COVID-19, as well as challenging illnesses such as cancer and diabetes. Aside from these applications, nanoscale metal-organic frameworks (nanoMOFs) have attracted much attention as novel efficient drug delivery systems for diverse pathologies. However, their potential as anti-COVID-19 therapeutic agents has not been investigated. Herein, we propose a pioneering anti-COVID MOF approach by studying their potential as safe and intrinsically antiviral agents through screening various nanoMOF. The iron(III)-trimesate MIL-100 showed a noteworthy antiviral effect against SARS-CoV-2 at the micromolar range, ensuring a high biocompatibility profile (90% of viability) in a real infected human cellular scenario. This research effectively paves the way toward novel antiviral therapies based on nanoMOFs, not only against SARS-CoV-2 but also against other challenging infectious and/or pulmonary diseases.

Crystal Clear: Metal-Organic Frameworks Pioneering the Path to Future Drug Detox

The growing number of acute drug abuse overdoses demands the development of innovative detoxification strategies for emergency purposes. In this study, an innovative approach for the application of porous Zr-based metal-organic frameworks for the treatment of acute overdoses of popular drugs of abuse including amphetamine, methamphetamine, cocaine, and MDMA is presented. A comprehensive approach determining the efficacy and the kinetics of drug removal, considering dosage, adsorption time, and adsorption mechanisms, was tested and corroborated with density functional theory (DFT) modeling. The experimental results showed high removal efficiency reaching up to 90% in the case of the application of the NU-1000 metal-organic framework. The difference Raman spectroscopy method presented in this study corroborated with DFT-based vibrational analysis allows the detection of drug adsorbed in the MOF framework even with as low a concentration as 5 mg/g. Additionally, the drug adsorption mechanisms were modeled with DFT, showing the π-π stacking in a vast majority of considered cases. The performance and influence on the living organisms were evaluated throughout the in vitro and in vivo experiments, indicating that Zr-based MOFs could serve as efficient, organic, safe drug adsorbents.

Long-lasting insecticidal activity in plants driven by chlorogenic acid-loaded metal-organic frameworks

Metal-organic frameworks (MOFs) possess a variety of interesting features related to their composition and structure that make them excellent candidates to be used in agriculture. However, few studies have reported their use as delivery agents of agrochemicals. In this work, the natural polyphenol chlorogenic acid (CGA) was entrapped via simple impregnation in the titanium aminoterephthalate MOF, MIL-125-NH2. A combination of experimental and computational techniques was used to understand and quantify the encapsulated CGA in MIL-125-NH2. Subsequently, CGA delivery studies were carried out in water at different pHs, showing a fast release of CGA during the first 2 h (17.3 ± 0.3% at pH = 6.5). In vivo studies were also performed against larvae of mealworm (Tenebrio molitor), evidencing the long-lasting insecticidal activity of CGA@MIL-125-NH2. This report demonstrates the potential of MOFs in the efficient release of agrochemicals, and paves the way to their study against in vivo models.

Towards a More Efficient Breast Cancer Therapy Using Active Human Cell Membrane-Coated Metal-Organic Frameworks

The recent description of well-defined molecular subtypes of breast cancer has led to the clinical development of a number of successful molecular targets. Particularly, triple-negative breast cancer (TNBC) is an aggressive type of breast cancer with historically poor outcomes, mainly due to the lack of effective targeted therapies. Recent progresses in materials science have demonstrated the impressive properties of metal-organic framework nanoparticles (NPs) as antitumoral drug delivery systems. Here, in a way to achieve efficient bio-interfaces with cancer cells and improve their internalization, benchmarked MIL-100(Fe) NPs were coated with cell membranes (CMs) derived from the human TNBC cell line MDA-MB-468. The prepared CMs-coated metal-organic framework (CMs_MIL-100(Fe)) showed enhanced colloidal stability, cellular uptake, and cytotoxicity in MDA-MB-468 cells compared to non-coated NPs, paving the way for these human CMs-coated MIL-100(Fe) NPs as effective targeted therapies against the challenging TNBC.

Nanocomposites Based on Magnetic Nanoparticles and Metal-Organic Frameworks for Therapy, Diagnosis, and Theragnostics

In the last two decades, metal-organic frameworks (MOFs) with highly tunable structure and porosity, have emerged as drug nanocarriers in the biomedical field. In particular, nanoscaled MOFs (nanoMOFs) have been widely investigated because of their potential biocompatibility, high drug loadings, and progressive release. To enhance their properties, MOFs have been combined with magnetic nanoparticles (MNPs) to form magnetic nanocomposites (MNP@MOF) with additional functionalities. Due to the magnetic properties of the MNPs, their presence in the nanosystems enables potential combinatorial magnetic targeted therapy and diagnosis. In this Review, we analyze the four main synthetic strategies currently employed for the fabrication of MNP@MOF nanocomposites, namely, mixing, in situ formation of MNPs in presynthesized MOF, in situ formation of MOFs in the presence of MNPs, and layer-by-layer methods. Additionally, we discuss the current progress in bioapplications, focusing on drug delivery systems (DDSs), magnetic resonance imaging (MRI), magnetic hyperthermia (MHT), and theragnostic systems. Overall, we provide a comprehensive overview of the recent advances in the development and bioapplications of MNP@MOF nanocomposites, highlighting their potential for future biomedical applications with a critical analysis of the challenges and limitations of these nanocomposites in terms of their synthesis, characterization, biocompatibility, and applicability.

Construction of Indium(III)-Organic Framework Based on a Flexible Cyclotriphosphazene-Derived Hexacarboxylate as a Reusable Green Catalyst for the Synthesis of Bioactive Aza-Heterocycles

The constant demand for eco-friendly methods of synthesizing complex organic compounds inspired researchers to design and develop modern, highly efficient heterogeneous catalytic systems. Herein, In-HCPCP metal-organic framework (SRMIST-1), a heterogeneous Lewis acid catalyst containing less toxic indium and eco-friendly robust cyclotriphosphazene and exhibiting notable chemical and thermal stability, durable catalytic activity, and exceptional reusability was produced through the reaction between indium(III) nitrate hydrate and hexakis(4-carboxylatophenoxy)-cyclotriphosphazene. In the SRMIST-1 structure, secondary building units {InO7} are assembled by a connection of η2- and η1-carboxylic oxo atoms from different HCPCP ligands, forming a three-dimensional network. The occurrence of regularly distributed In(III) sites in SRMIST-1 confers superior reactivity on the catalyst toward the synthesis of 2,3-dihydroquinazolin-4(1H)-ones and 3,4-dihydro-2H-1,2,4-benzothiadiazine-1,1-dioxides by the cyclization reaction of 2-aminobenzamides and 2-aminobenzenesulphonamides with aldehydes under optimized reaction conditions, respectively. The notable features of this method include broad functional group compatibility, low catalyst loading (1-5 mol %), mild reaction conditions, easy workup procedures, good to excellent reaction yields, ethanol as a green solvent, reusability of the catalyst (five cycles), and economic attractiveness, which is mainly due to sustainability of SRMIST-1 as a reusable green catalyst. Our findings demonstrate that the highly reactive and reusable green catalyst finds widespread applications in medicinal chemistry.

Red blood cell membrane-coated functionalized Cu-doped metal organic framework nanoformulations as a biomimetic platform for improved chemo-/chemodynamic/photothermal synergistic therapy

Nanoformulations for combining chemotherapy, chemodynamic therapy, and photothermal therapy have enormous potential in tumor treatment. Coating nanoformulations with cell membranes endows them with homologous cellular mimicry, enabling nanoformulations to acquire new functions and properties, including homologous targeting and long circulation in vivo, and can enhance internalization by homologous cancer cells. Herein, we fused multifunctional biomimetic nanoformulations based on Cu-doped zeolitic imidazolate framework-8 (ZIF-8). Hydroxycamptothecin (HCPT), a clinical anti-tumor drug, was encapsulated into ZIF-8, which was subsequently coated with polydopamine (PDA) and red blood cell membrane. The as-fabricated biomimetic nanoformulations showed an enhanced cell uptake in vitro and the potential to prolong blood circulation in vivo, producing effective synergistic chemotherapy, chemodynamic therapy, and photothermal therapy under the 808 nm laser irradiation. Together, the biomimetic nanoformulations showed a prolonged blood circulation and evasion of immune recognition in vivo to provide a bio-inspired strategy which may have the potential for the multi-synergistic therapy of breast cancer.

Mitochondrial topoisomerase 1 targeted anticancer therapy using irinotecan encapsulated mesoporous MIL-101(Fe) synthesized via a vapour assisted method

Mitochondrial topisomerase 1 (Top1mt) is critical for mtDNA replication, transcription, and energy production. Here, we investigate the carrier-mediated targeted delivery of the anticancer drug irinotecan into the mitochondria to selectively trap Top1mt covalent complexes (Top1mtcc) and its role in anticancer therapeutics. We have designed a biocompatible mesoporous metal-organic framework (MOF) material, namely MIL-101(Fe), as the drug delivery carrier that selectively localizes inside mitochondria. In contrast to the traditional way of synthesising MOFs, here we have employed a vapour-assisted solvothermal method for the synthesis of MIL-101(Fe) using terephthalic acid as the organic linker and Fe(III) as the metal source. The advantage of this method is that it recycles the excess solvent (DMF) and reduces the amount of washing solvent. We demonstrate that MIL-101(Fe)-encapsulated irinotecan (MIL-Iri) was selectively targeted towards the mitochondria to poison Top1mtcc in a dose-dependent manner and was achieved at a low nanomolar drug concentration. We provide evidence that Top1mtcc generated by MIL-Iri leads to mtDNA damage in human colon and breast cancer cells and plays a significant role in cellular toxicity. Altogether, this study provides evidence for a new and effective strategy in anticancer chemotherapy.

Exceptionally Stable And Super-Efficient Electrocatalysts Derived From Semiconducting Metal Phosphonate Frameworks

Two new isostructural semiconducting metal-phosphonate frameworks are reported. Co2 [1,4-NDPA] and Zn2 [1,4-NDPA] (1,4-NDPA4- is 1,4-naphthalenediphosphonate) have optical bandgaps of 1.7 eV and 2.5 eV, respectively. The electrocatalyst derived from Co2 [1,4-NPDA] as a precatalyst generated a low overpotential of 374 mV in the oxygen evolution reaction (OER) with a Tafel slope of 43 mV dec-1 at a current density of 10 mA cm-2 in alkaline electrolyte (1 mol L-1 KOH), which is indicative of remarkably superior reaction kinetics. Benchmarking of the OER of Co2 [1,4-NPDA] material as a precatalyst coupled with nickel foam (NF) showed exceptional long-term stability at a current density of 50 mA cm-2 for water splitting compared to the state-of-the-art Pt/C/RuO2 @NF after 30 h in 1 mol L-1 KOH. In order to further understand the OER mechanism, the transformation of Co2 [1,4-NPDA] into its electrocatalytically active species was investigated.

The green synthesis and applications of biological metal-organic frameworks for targeted drug delivery and tumor treatments

Biological metal-organic frameworks (bio-MOFs) constitute a growing subclass of MOFs composed of metals and bio-ligands derived from biology, such as nucleobases, peptides, saccharides, and amino acids. Bio-ligands are more abundant than other traditional organic ligands, providing multiple coordination sites for MOFs. However, bio-MOFs are typically prepared using hazardous or harmful solvents or reagents, as well as laborious processes that do not conform to environmentally friendly standards. To improve biocompatibility and biosafety, eco-friendly synthesis and functionalization techniques should be employed with mild conditions and safer materials, aiming to reduce or avoid the use of toxic and hazardous chemical agents. Recently, bio-MOF applications have gained importance in some research areas, including imaging, tumor therapy, and targeted drug delivery, owing to their flexibility, low steric hindrances, low toxicity, remarkable biocompatibility, surface property refining, and degradability. This has led to an exponential increase in research on these materials. This paper provides a comprehensive review of updated strategies for the synthesis of environmentally friendly bio-MOFs, as well as an examination of the current progress and accomplishments in green-synthesized bio-MOFs for drug delivery aims and tumor treatments. In conclusion, we consider the challenges of applying bio-MOFs for biomedical applications and clarify the possible research orientation that can lead to highly efficient therapeutic outcomes.

Improving curcumin bactericidal potential against multi-drug resistant bacteria via its loading in polydopamine coated zinc-based metal-organic frameworks

Multi-drug resistant (MDR) bactearial strains have posed serious health issues, thus leading to a significant increase in mortality, morbidity, and the expensive treatment of infections. Metal-organic frameworks (MOFs), comprising metal ions and a variety of organic ligands, have been employed as an effective drug deliveryy vehicle due to their low toxicity, biodegradability, higher structural integrity and diverse surface functionalities. Polydopamine (PDA) is a versatile biocompatible polymer with several interesting properties, including the ability to adhere to biological surfaces. As a result, modifying drug delivery vehicles with PDA has the potential to improve their antimicrobial properties. This work describes the preparation of PDA-coated Zn-MOFs for improving curcumin's antibacterial properties against S. aureus and E. coli. Powder X-ray diffraction (P-XRD), FT-IR, scanning electron microscopy (SEM), and DLS were utilized to characterize PDA-coated Zn-MOFs. The curcumin loading and in vitro release of the prepared MOFs were also examined. Finally, the MOFs were tested for bactericidal ability against E. coli and S. aureus using an anti-bacterial assay and surface morphological analysis. Smaller size MOFs were capable of loading and releasing curcumin. The findings showed that as curcumin was encapsulated into PDA-coated MOFs, its bactericidal potential was significantly enhanced, and the findings were further supported by SEM which indicated the complete morphological distortion of the bacteria after treatment with PDA-Cur-Zn-MOFs. These studies clearly indicate that the PDA-Cur-Zn-MOFs developed in this study are extremely promising for long-term release of drugs to treat a wide range of microbial infections.

Current status and prospects of MIL-based MOF materials for biomedicine applications

This article mainly reviews the biomedicine applications of two metal-organic frameworks (MOFs), MIL-100(Fe) and MIL-101(Fe). These MOFs have advantages such as high specific surface area, adjustable pore size, and chemical stability, which make them widely used in drug delivery systems. The article first introduces the properties of these two materials and then discusses their applications in drug transport, antibacterial therapy, and cancer treatment. In cancer treatment, drug delivery systems based on MIL-100(Fe) and MIL-101(Fe) have made significant progress in chemotherapy (CT), chemodynamic therapy (CDT), photothermal therapy (PTT), photodynamic therapy (PDT), immunotherapy (IT), nano-enzyme therapy, and related combined therapy. Overall, these MIL-100(Fe) and MIL-101(Fe) materials have tremendous potential and diverse applications in the field of biomedicine.

Designs of metal-organic framework nanoparticles for protein delivery

Recently, there has been high interest in developing metal-organic framework (MOF) nanoparticles (NPs) for delivering therapeutic proteins, propelled mainly by the unique hierarchical porous structures of MOFs for protein encapsulation. Novel design strategies have emerged for broad therapeutic applications and clinical translations, leading to multifunctional MOF-NPs with improved biointerfacing capabilities and higher potency. This review summarizes recent MOF-NP designs specifically for protein delivery. The summary focuses on four design categories, including environment-responsive MOF-NPs for on-demand protein delivery, cell membrane-coated MOF-NPs for biomimetic protein delivery, cascade reaction-incorporated MOF-NPs for combinatorial protein delivery, and composite MOF-NPs for intelligent protein delivery. The major challenges and opportunities in using MOF-NPs for protein delivery are also discussed. Overall, this review will promote designs of MOF-NPs with unique properties to address unmet medical needs.

Therapy and diagnosis of Alzheimer's disease: from discrete metal complexes to metal-organic frameworks

Alzheimer's disease (AD) is a neurodegenerative disorder affecting 44 million people worldwide. Although many issues (pathogenesis, genetics, clinical features, and pathological aspects) are still unknown, this disease is characterized by noticeable hallmarks such as the formation of β-amyloid plaques, hyperphosphorylation of tau proteins, the overproduction of reactive oxygen species, and the reduction of acetylcholine levels. There is still no cure for AD and the current treatments are aimed at regulating the cholinesterase levels, attenuating symptoms temporarily rather than preventing the AD progression. In this context, coordination compounds are regarded as a promissing tool in AD treatment and/or diagnosis. Coordination compounds (discrete or polymeric) possess several features that make them an interesting option for developing new drugs for AD (good biocompatibility, porosity, synergetic effects of ligand-metal, fluorescence, particle size, homogeneity, monodispersity, etc.). This review discusses the recent progress in the development of novel discrete metal complexes and metal-organic frameworks (MOFs) for the treatment, diagnosis and theragnosis of AD. These advanced therapies for AD treatment are organized according to the target: Aβ peptides, hyperphosphorylated tau proteins, synaptic dysfunction, and mitochondrial failure with subsequent oxidative stress.

Recent Advances of Metal-Polyphenol Coordination Polymers for Biomedical Applications

Nanomedicine has provided cutting-edge technologies and innovative methods for modern biomedical research, offering unprecedented opportunities to tackle crucial biomedical issues. Nanomaterials with unique structures and properties can integrate multiple functions to achieve more precise diagnosis and treatment, making up for the shortcomings of traditional treatment methods. Among them, metal-polyphenol coordination polymers (MPCPs), composed of metal ions and phenolic ligands, are considered as ideal nanoplatforms for disease diagnosis and treatment. Recently, MPCPs have been extensively investigated in the field of biomedicine due to their facile synthesis, adjustable structures, and excellent biocompatibility, as well as pH-responsiveness. In this review, the classification of various MPCPs and their fabrication strategies are firstly summarized. Then, their significant achievements in the biomedical field such as biosensing, drug delivery, bioimaging, tumor therapy, and antibacterial applications are highlighted. Finally, the main limitations and outlooks regarding MPCPs are discussed.

Research development of porphyrin-based metal-organic frameworks: targeting modalities and cancer therapeutic applications

Porphyrins are naturally occurring organic molecules that have attracted widespread attention for their potential in the field of biomedical research. Porphyrin-based metal-organic frameworks (MOFs) that utilize porphyrin molecules as organic ligands have gained attention from researchers due to their excellent results as photosensitizers in tumor photodynamic therapy (PDT). Additionally, MOFs hold significant promise and potential for other tumor therapeutic approaches due to their tunable size and pore size, excellent porosity, and ultra-high specific surface area. Active delivery of nanomaterials via targeted molecules for tumor therapy has demonstrated greater accumulation, lower drug doses, higher therapeutic efficacy, and reduced side effects relative to passive targeting through the enhanced permeation and retention effect (EPR). This paper presents a comprehensive review of the targeting methods employed by porphyrin-based MOFs in tumor targeting therapy over the past few years. It further discusses the applications of porphyrin-based MOFs for targeted cancer therapy through various therapeutic methods. The objective of this paper is to provide a valuable reference and source of ideas for targeted therapy using porphyrin-based MOF materials and to inspire further exploration of their potential in the field of cancer therapy.

Schottky Junction Nanozyme Based on Mn-Bridged Co-Phthalocyanines and Ti3C2Tx Nanosheets Boosts Integrative Type I and II Photosensitization for Multimodal Cancer Therapy

Cancer phototheranostics have the potential for significantly improving the therapeutic effectiveness, as it can accurately diagnose and treat cancer. However, the current phototheranostic platforms leave much to be desired and are often limited by tumor hypoxia. Herein, a Schottky junction nanozyme has been established between a manganese-bridged cobalt-phthalocyanines complex and Ti₃C₂T_x MXene nanosheets (CoPc-Mn/Ti₃C₂T_x), which can serve as an integrative type I and II photosensitizer for enhancing cancer therapeutic efficacy via a photoacoustic imaging-guided multimodal chemodynamic/photothermal/photodynamic therapy strategy under near-infrared (808 nm) light irradiation. The Schottky junction not only possessed a narrow-bandgap, enhanced electron-hole separation ability and exhibited a potent redox potential but also enabled improved H₂O₂ and O₂ supplying performances in vitro. Accordingly, the AS1411 aptamer-immobilized CoPc-Mn/Ti₃C₂T_x nanozyme illustrated high accuracy and excellent anticancer efficiency through a multimodal therapy strategy in in vitro and in vivo experiments. This work presents a valuable method for designing and constructing a multifunctional nanocatalytic medicine platform for synergistic cancer therapy of solid tumors.

H2O2/O2 self-supply and Ca2+ overloading MOF-based nanoplatform for cascade-amplified chemodynamic and photodynamic therapy

Introduction: Reactive oxygen species (ROS)-mediated therapies have typically been considered as noninvasive tumor treatments owing to their high selectivity and efficiency. However, the harsh tumor microenvironment severely impairs their efficiency. Methods: Herein, the biodegradable Cu-doped zeolitic imidazolate framework-8 (ZIF-8) was synthesized for loading photosensitizer Chlorin e6 (Ce6) and CaO₂ nanoparticles, followed by surface decoration by hyaluronic acid (HA), obtaining HA/CaO₂-Ce6@Cu-ZIF nano platform. Results and Discussion: Once HA/CaO₂-Ce6@Cu-ZIF targets tumor sites, the degradation of Ce6 and CaO₂ release from the HA/CaO₂-Ce6@Cu-ZIF in response to the acid environment, while the Cu²⁺ active sites on Cu-ZIF are exposed. The released CaO₂ decompose to generate hydrogen peroxide (H₂O₂) and oxygen (O₂), which alleviate the insufficiency of intracellular H₂O₂ and hypoxia in tumor microenvironment (TME), effectively enhancing the production of hydroxyl radical (•OH) and singlet oxygen (¹O₂) in Cu²⁺-mediated chemodynamic therapy (CDT) and Ce6-induced photodynamic therapy (PDT), respectively. Importantly, Ca²⁺ originating from CaO₂ could further enhance oxidative stress and result in mitochondrial dysfunction induced by Ca²⁺ overloading. Conclusion: Thus, the H₂O₂/O₂ self-supplying and Ca²⁺ overloading ZIF-based nanoplatform for cascade-amplified CDT/PDT synergistic strategy is promising for highly efficient anticancer therapy.

Metal-Organic Frameworks as Sensors for Human Amyloid Diseases

Metal-organic frameworks (MOFs) are versatile compounds with emergent applications in the fabrication of biosensors for amyloid diseases. They hold great potential in biospecimen protection and unprecedented probing capabilities for optical and redox receptors. In this Review, we summarize the main methodologies employed in the fabrication of MOF-based sensors for amyloid diseases and collect all available data in the literature related to their performance (detection range, limit of detection, recovery, time of analysis, among other parameters). Nowadays, MOF sensors have evolved to a point where they can, in some cases, outperform technologies employed in the detection of several amyloid biomarkers (amyloid β peptide, α-synuclein, insulin, procalcitonin, and prolactin) present in biological fluids, such as cerebrospinal fluid and blood. A special emphasis has been given by researchers on Alzheimer's disease monitoring to the detriment of other amyloidosis that are underexploited despite their societal relevance (e.g., Parkinson's disease). There are still important obstacles to overcome in order to selectively detect the various peptide isoforms and soluble amyloid species associated with Alzheimer's disease. Furthermore, MOF contrast agents for imaging peptide soluble oligomers in living humans are also scarce (if not nonexistent), and action in this direction is unquestionably required to clarify the contentious link between the amyloidogenic species and the disease, guiding research toward the most promising therapeutic strategies.

Interrogating Encapsulated Protein Structure within Metal-Organic Frameworks at Elevated Temperature

Encapsulating biomacromolecules within metal-organic frameworks (MOFs) can confer thermostability to entrapped guests. It has been hypothesized that the confinement of guest molecules within a rigid MOF scaffold results in heightened stability of the guests, but no direct evidence of this mechanism has been shown. Here, we present a novel analytical method using small-angle X-ray scattering (SAXS) to solve the structure of bovine serum albumin (BSA) while encapsulated within two zeolitic imidazolate frameworks (ZIF-67 and ZIF-8). Our approach comprises subtracting the scaled SAXS spectrum of the ZIF from that of the biocomposite BSA@ZIF to determine the radius of gyration of encapsulated BSA through Guinier, Kratky, and pair distance distribution function analyses. While native BSA exposed to 70 °C became denatured, in situ SAXS analysis showed that encapsulated BSA retained its size and folded state at 70 °C when encapsulated within a ZIF scaffold, suggesting that entrapment within MOF cavities inhibited protein unfolding and thus denaturation. This method of SAXS analysis not only provides insight into biomolecular stabilization in MOFs but may also offer a new approach to study the structure of other conformationally labile molecules in rigid matrices.

Nanosized metal-organic frameworks as unique platforms for bioapplications

Metal-organic frameworks (MOFs) are extremely versatile materials, which serve to create platforms with exceptional porosity and specific reactivities. The production of MOFs at the nanoscale (NMOFs) offers the possibility of creating innovative materials for bioapplications as long as they maintain the properties of their larger counterparts. Due to their inherent chemical versatility, synthetic methods to produce them at the nanoscale can be combined with inorganic nanoparticles (NPs) to create nanocomposites (NCs) with one-of-a-kind features. These systems can be remotely controlled and can catalyze abiotic reactions in living cells, which have the potential to stimulate further research on these nanocomposites as tools for advanced therapies.

Antiadherent AgBDC Metal-Organic Framework Coating for Escherichia coli Biofilm Inhibition

Surface microbial colonization and its potential biofilm formation are currently a major unsolved problem, causing almost 75% of human infectious diseases. Pathogenic biofilms are capable of surviving high antibiotic doses, resulting in inefficient treatments and, subsequently, raised infection prevalence rates. Antibacterial coatings have become a promising strategy against the biofilm formation in biomedical devices due to their biocidal activity without compromising the bulk material. Here, we propose for the first time a silver-based metal-organic framework (MOF; here denoted AgBDC) showing original antifouling properties able to suppress not only the initial bacterial adhesion, but also the potential surface contamination. Firstly, the AgBDC stability (colloidal, structural and chemical) was confirmed under bacteria culture conditions by using agar diffusion and colony counting assays, evidencing its biocide effect against the challenging E. coli, one of the main representative indicators of Gram-negative resistance bacteria. Then, this material was shaped as homogeneous spin-coated AgBDC thin film, investigating its antifouling and biocide features using a combination of complementary procedures such as colony counting, optical density or confocal scanning microscopy, which allowed to visualize for the first time the biofilm impact generated by MOFs via a specific fluorochrome, calcofluor.

Naringin@Metal-Organic Framework as a Multifunctional Bioplatform

Naringin, a natural product, can be used as a therapeutic agent due to its low systemic toxicity and negligible adverse effect. However, due to its hydrophobic nature and thereby low solubility, high-dose treatment is required when used for human therapy. Herein, we demonstrate the employment of a metal-organic framework (MOF) as a nontoxic loading carrier to encapsulate naringin, and the afforded nairngin@MOF composite can serve as a multifunctional bioplatform capable of treating Gram-positive bacteria and certain cancers by slowly and progressively releasing the encapsulated naringin as well as improving and modulating immune system functions through synergy between naringin and the MOF.

Fabrication and application of cisplatin-loaded mesoporous magnetic nanobiocomposite: a novel approach to smart cervical cancer chemotherapy

There are significant challenges in developing drug carriers for therapeutic perspective. We have investigated a novel nanocarrier system, based on combining functionalized magnetic nanocomposite with Metal–Organic Frameworks (MOFs). Magnetic nanoparticles modified using biocompatible copolymers may be suitable for delivering hydrophobic drugs, such as cisplatin. Furthermore, compared to polymeric nanocarriers, nanocomposite constructed from zeolitic imidazolate framework-8 (ZIF-8) have demonstrated better drug loading capacity, as well as excellent pH-triggered drug release. Cisplatin-encapsulated Fe3O4@SiO2-ZIF-8@N-Chit-FA has been evaluated to determine the antitumor effects of free cisplatin enhancement in cervical cancer cells. In order to increase the stability of the proposed nanocarrier in aqueous solutions, in addition to the density of functional groups, a nano-chitosan layer was coated on top of the magnetic nanocomposite. It was then added with cisplatin onto the surface of Fe3O4@SiO2-ZIF-8@N-Chit-FA to deliver anticancer treatment that could be targeted using a magnetic field. A mouse isograft model of TC1 cells was used to evaluate the in vivo tumor growth inhibition. In tumor-bearing mice, Fe3O4@SiO2-ZIF-8@N-Chit-FA-cisplatin was injected intraperitoneally, and the targeted delivery was amplified by an external magnet (10 mm by 10 mm, surface field strength 0.4 T) fixed over the tumor site. Based on in vivo results, cisplatin-Loaded Mesoporous Magnetic Nanobiocomposite inhibited the growth of cervical tumors (P < 0.001) through the induction of tumor necrosis (P < 0.05) when compared to cisplatin alone. With the application of an external magnetic field, the drug was demonstrated to be able to induce its effects on specific target areas. In summary, Fe3O4 @ SiO2-ZIF-8 @ N-Chit-FA nanocomposites have the potential to be implemented in targeted nanomedicine to deliver bio-functional molecules.

Metal-Organic Frameworks as Intelligent Drug Nanocarriers for Cancer Therapy

Metal-organic frameworks (MOFs) are crystalline porous materials with periodic network structures formed by self-assembly of metal ions and organic ligands. Attributed to their tunable composition and pore size, ultrahigh surface area (1000-7000 m²/g) and pore volume (1.04-4.40 cm³/g), easy surface modification, appropriate physiological stability, etc., MOFs have been widely used in biomedical applications in the last two decades, especially for the delivery of bioactive agents. In the initial stage, MOFs were widely used to load small molecule drugs with ultra-high doses. Whereafter, more recent work has focused on the load of biomacromolecules, such as nucleic acids and proteins. Over the past years, we have devoted extensive effort to investigate the function of MOF materials for bioactive agent delivery. MOFs can be used not only as an intelligent nanocarrier to deliver or protect bioactive agents but also as an activator for their release or activation in response to the different microenvironments. Altogether, this review details the current progress of MOF materials for bioactive agent delivery and looks into their future development.

Antibacterial Activity of Two Zn-MOFs Containing a Tricarboxylate Linker

Metal-organic frameworks (MOFs) can be used as reservoirs of metal ions with relevant antibacterial effects. Here, two novel Zn-based MOFs with the formulas [Zn₄(μ₄-O)(μ-FA)L₂] (GR-MOF-8) and [Zn₄(μ₄-O)L₂(H₂O)] (GR-MOF-9) (H₃L: 5-((4-carboxyphenyl)ethynyl) in isophthalic acid and FA (formate anion) were solvothermally synthetized and fully characterized. The antibacterial activity of GR-MOF-8 and 9 was investigated against Staphylococcus aureus (SA) and Escherichia Coli (EC) by the agar diffusion method. Both bacteria are among the most relevant human and animal pathogens, causing a wide variety of infections, and are often related with the development of antimicrobial resistances. While both Zn-based materials exhibited antibacterial activity against both strains, GR-MOF-8 showed the highest inhibitory action, likely due to a more progressive Zn release under the tested experimental conditions. This is particularly evidenced in the inhibition of SA, with an increasing effect of GR-MOF-8 with time, which is of great significance to ensure the disappearance of the microorganism.

Recent Advances in Metal-Organic Frameworks for Applications in Magnetic Resonance Imaging

Diagnostics is an important part of medical practice. The information required for diagnosis is typically collected by performing diagnostic tests, some of which include imaging. Magnetic resonance imaging (MRI) is one of the most widely used and effective imaging techniques. To improve the sensitivity and specificity of MRI, contrast agents are used. In this review, the usage of metal-organic frameworks (MOFs) and composite materials based on them as contrast agents for MRI is discussed. MOFs are crystalline porous coordination polymers. Due to their huge design variety and high density of metal ions, they have been studied as a highly promising class of materials for developing MRI contrast agents. This review highlights the most important studies and focuses on the progress of the field over the last five years. The materials are classified based on their design and structural properties into three groups: MRI-active MOFs, composite materials based on MOFs, and MRI-active compounds loaded in MOFs. Moreover, an overview of MOF-based materials for heteronuclear MRI including 129Xe and 19F MRI is given.

Glycopolymer-Functionalized MOF-808 Nanoparticles as a Cancer-Targeted Dual Drug Delivery System for Carboplatin and Floxuridine

Codelivery of chemotherapeutics via nanomaterials has attracted much attention over the last decades due to improved drug delivery to tumor tissues, decreased systemic effects, and increased therapeutic efficacies. High porosities, large pore volumes and surface areas, and tunable structures have positioned metal-organic frameworks (MOFs) as promising drug delivery systems (DDSs). In particular, nanoscale Zr-linked MOFs such as MOF-808 offer notable advantages for biomedical applications such as high porosity, good stability, and biocompatibility. In this study, we report efficient dual drug delivery of floxuridine (FUDR) and carboplatin (CARB) loaded in MOF-808 nanoparticles to cancer cells. The nanoparticles were further functionalized by a poly(acrylic acid-mannose acrylamide) (PAAMAM) glycopolymer coating to obtain a highly selective DDS in cancer cells and enhance the therapeutic efficacy of chemotherapy. While MOF-808 was found to enhance the individual therapeutic effects of FUDR and CARB toward cancerous cells, combining FUDR and CARB was seen to cause a synergistic effect, further enhancing the cytotoxicity of the free drugs. Enhancement of CARB loading and therefore cytotoxicity of the CARB-loaded MOFs could be induced through a modified activation protocol, while coating of MOF-808 with the PAAMAM glycopolymer increased the uptake of the nanoparticles in cancer cells used in the study and offered a particularly significant selective drug delivery with high cytotoxicity in HepG2 human hepatocellular carcinoma cells. These results show how the enhancement of cytotoxicity is possible through both nanovector delivery and synergistic treatment, and that MOF-808 is a viable candidate for future drug delivery studies.

Advances in plasmonic-based MOF composites, their bio-applications and perspectives in this field

INTRODUCTION

Nanomaterials have been used for bio-applications since the late 20st century. In an attempt to tailor and optimize their properties, and by extension their efficiency, composites have attracted considerable attention. In this regard, recent studies on plasmonic nanoparticles and metal-organic framework (NP@MOF) composites suggested these materials show great promise in this field.

AREAS COVERED

This review focused on the more recent scientific advances in the synthetic strategies to optimize plasmonic MOF nanocomposites currently available, as well as their bio-application, particularly as biosensors and therapy.

EXPERT OPINION

Plasmonic MOF nanocomposites have shown great potential as they combine the properties of both materials with proven efficiency in bio-application. On the one hand, nanoMOFs have proven their potential particularly as drug nanocarriers, owing to their exceptional porosity and tunability. On the other hand, plasmonic nanoparticles have been an asset for imaging and phototherapy. Different strategies have been reported to develop these nanocomposites, mainly including core-shell, encapsulation, and in situ reduction. In addition, advanced composite structures should be considered, such as mixed metal nanoparticles, hollow structures or the combination of several approaches. Specifically, plasmonic MOF nanocomposites prove to be attractive stimuli responsive drug delivery systems, phototherapeutic agents as well as highly sensitive biosensors.

Tunable fluorescence emission based on multi-layered MOF-on-MOF

Luminescent metal-organic frameworks (MOFs) have garnered considerable attention in various fields. Herein, we proposed a hierarchical confinement strategy based on MOF-on-MOF to tune luminescence emission ranging from blue to red including white light in a flexible way. The easily available ZIF-8 MOF was used as a host for the confinement of two kinds of size-matching dyes (perylene and rhodamine B) to obtain a layered ZIF-8@dye@ZIF-8@dye via in situ encapsulation and seed-mediated synthesis. ZIF-8@dye@ZIF-8@dye materials with different fluorescence emission in dispersed and solid states were both obtained by tuning the initial encapsulation concentration of dye and changing the structure of the inner and outer ZIF-8@dye layers. To our delight, ZIF-8@0.125perylene@ZIF-8@25RhB with white light emission in the dispersed state was obtained; meanwhile, ZIF-8@0.125perylene + 25RhB and mechanically mixed ZIF-8@0.125perylene + ZIF-8@25RhB could not realize white light emission under the same conditions, indicating that the proposed hierarchical confinement strategy facilitated white light regulation. Similarly, the emission of ZIF-8@dye@ZIF-8@dye in the solid state has also been investigated; ZIF-8@perylene@ZIF-8@3RhB with white light emission was obtained, while white light emission could not be achieved in ZIF-8@perylene + 3RhB and ZIF-8@perylene + ZIF-8@3RhB, which further indicated the importance of the hierarchical confinement strategy based on MOF-on-MOF. The proposed hierarchical confinement strategy may also inspire the development of other functional optical MOF materials.

Metal-Organic Frameworks in Agriculture

Agrochemicals, which are crucial to meet the world food qualitative and quantitative demand, are compounds used to kill pests (insects, fungi, rodents, or unwanted plants). Regrettably, there are some important issues associated with their widespread and extensive use (e.g., contamination, bioaccumulation, and development of pest resistance); thus, a reduced and more controlled use of agrochemicals and thorough detection in food, water, soil, and fields are necessary. In this regard, the development of new functional materials for the efficient application, detection, and removal of agrochemicals is a priority. Metal-organic frameworks (MOFs) with exceptional sorptive, recognition capabilities, and catalytical properties have very recently shown their potential in agriculture. This Review emphasizes the recent advances in the use of MOFs in agriculture through three main views: environmental remediation, controlled agrochemical release, and detection of agrochemicals.

Engineering single-atom catalysts toward biomedical applications

Due to inherent structural defects, common nanocatalysts always display limited catalytic activity and selectivity, making it practically difficult for them to replace natural enzymes in a broad scope of biologically important applications. By decreasing the size of the nanocatalysts, their catalytic activity and selectivity will be substantially improved. Guided by this concept, the advances of nanocatalysts now enter an era of atomic-level precise control. Single-atom catalysts (denoted as SACs), characterized by atomically dispersed active sites, strikingly show utmost atomic utilization, precisely located metal centers, unique metal-support interactions and identical coordination environments. Such advantages of SACs drastically boost the specific activity per metal atom, and thus provide great potential for achieving superior catalytic activity and selectivity to functionally mimic or even outperform natural enzymes of interest. Although the size of the catalysts does matter, it is not clear whether the guideline of "the smaller, the better" is still correct for developing catalysts at the single-atom scale. Thus, it is clearly a new, urgent issue to address before further extending SACs into biomedical applications, representing an important branch of nanomedicine. This review begins by providing an overview of recent advances of synthesis strategies of SACs, which serve as a basis for the discussion of emerging achievements in improving the enzyme-like catalytic properties at an atomic level. Then, we carefully compare the structures and functions of catalysts at various scales from nanoparticles, nanoclusters, and few-atom clusters to single atoms. Contrary to conventional wisdom, SACs are not the most catalytically active catalysts in specific reactions, especially those requiring multi-site auxiliary activities. After that, we highlight the unique roles of SACs toward biomedical applications. To appreciate these advances, the challenges and prospects in rapidly growing studies of SACs-related catalytic nanomedicine are also discussed in this review.

Reticular Nanoscience: Bottom-Up Assembly Nanotechnology

The chemistry of metal-organic and covalent organic frameworks (MOFs and COFs) is perhaps the most diverse and inclusive among the chemical sciences, and yet it can be radically expanded by blending it with nanotechnology. The result is reticular nanoscience, an area of reticular chemistry that has an immense potential in virtually any technological field. In this perspective, we explore the extension of such an interdisciplinary reach by surveying the explored and unexplored possibilities that framework nanoparticles can offer. We localize these unique nanosized reticular materials at the juncture between the molecular and the macroscopic worlds, and describe the resulting synthetic and analytical chemistry, which is fundamentally different from conventional frameworks. Such differences are mirrored in the properties that reticular nanoparticles exhibit, which we described while referring to the present state-of-the-art and future promising applications in medicine, catalysis, energy-related applications, and sensors. Finally, the bottom-up approach of reticular nanoscience, inspired by nature, is brought to its full extension by introducing the concept of augmented reticular chemistry. Its approach departs from a single-particle scale to reach higher mesoscopic and even macroscopic dimensions, where framework nanoparticles become building units themselves and the resulting supermaterials approach new levels of sophistication of structures and properties.

Anti-VEGFR2-labeled enzyme-immobilized metal-organic frameworks for tumor vasculature targeted catalytic therapy

Tumor vasculature-targeting therapy either using angiogenesis inhibitors or vascular disrupting agents offers an important new avenue for cancer therapy. In this work, a tumor-specific catalytic nanomedicine for enhanced tumor ablation accompanied with tumor vasculature disruption and angiogenesis inhibition was developed through a cascade reaction with enzyme glucose oxidase (GOD) modified on Fe-based metal organic framework (Fe-MOF) coupled with anti-VEGFR2.The GOD enzyme could catalyze the intratumoral glucose decomposition to trigger tumor starvation and yet provide abundant hydrogen peroxide as the substrate for Fenton-like reaction catalyzed by Fe-MOF to produce sufficient highly toxic hydroxyl radicals for enhanced chemodynamic therapy and instantly attacked tumor vascular endothelial cells to destroy the existing vasculature, while the anti-VEGFR2 antibody guided the nanohybrids to target blood vessels and block the VEGF-VEGFR2 connection to prevent angiogenesis. Both in vitro and in vivo results demonstrated the smart nanohybrids could cause the tumor cell apoptosis and vasculature disruption, and exhibited enhanced tumor regression in A549 xenograft tumor-bearing mice model. This study suggested that synergistic targeting tumor growth and its vasculature network would be more promising for curing solid tumors. STATEMENT OF SIGNIFICANCE: Cooperative destruction of tumor cells and tumor vasculature offers a potential avenue for cancer therapy. Under this premise, a tumor-specific catalytic nanomedicine for enhanced tumor ablation accompanied with tumor vasculature disruption and new angiogenesis inhibition was developed through a cascade reaction with glucose oxidase modified on the surface of iron-based metal organic framework coupled with VEGFR2 antibody. The resulting data demonstrated that a therapeutic regimen targeting tumor growth as well as its vasculature with both existing vasculature disruption and neovasculature inhibition would be more potential for complete eradication of tumors.

Design and degradation of permanently porous vitamin C and zinc-based metal-organic framework

Bioapplication is an emerging field of metal-organic frameworks (MOF) utilization, but biocompatible MOFs with permanent porosity are still a rarity in the field. In addition, biocompatibility of MOF constituents is often overlooked when designing bioMOF systems, intended for drug delivery. Herein, we present the a Zn(II) bioMOF based on vitamin C as an independent ligand (bioNICS-1) forming a three-dimensional chiral framework with permanent microporosity. Comprehensive study of structure stability in biorelavant media in static and dynamic conditions demonstrates relatively high structure resistivity, retaining a high degree of its parent specific surface area. Robustness of the 3D framework enables a slow degradation process, resulting in controllable release of bioactive components, as confirmed by kinetic studies. BioNICS-1 can thus be considered as a suitable candidate for the design of a small drug molecule delivery system, which was demonstrated by successful loading and release of urea-a model drug for topical application-within and from the MOF pores.

Hygroscopic metal-organic framework MIL-160(Al): In-situ time-dependent ATR-FTIR and gravimetric study of mechanism and kinetics of water vapor sorption

Metal-organic frameworks (MOFs) are advanced highly porous coordination polymers of high interest to separations, environmental remediation, catalysis, and biomedicine. While many MOFs are unstable in water and aqueous solutions, aluminum MOFs (Al-MOFs) offer an unprecedented stability. First, we synthesize unusual highly hygroscopic Al-MOF MIL-160(Al), purify it and assign FTIR peaks to specific groups as potential water binding sites. Further, we introduce a novel method of in-situ time-dependent ATR-FTIR spectroscopy to detect specific binding sites in MIL-160(Al) and investigate the progress of reaction. Specifically, we combine in-situ time-dependent ATR-FTIR spectroscopy with using water as "spectroscopic probe" to determine binding sites in MIL-160(Al) and their evolution during the reaction. The in-situ time-dependent ATR-FTIR spectra provide evidence of water bonding to: the μ-OH group, the carboxylate anion COO^- in 2,5-FDCA^2- linker, oxygen atom in the furan ring of the linker, and the C-C and C-H bonds of the furan ring of the linker. Then, we conduct mechanistic and kinetic study of sorption of water vapor on MIL-160(Al) in air using the combination of two complementary in-situ time-dependent methods: the ATR-FTIR spectroscopy and gravimetric analysis. Water vapor sorption on MIL-160(Al) results in the solid-state adsorption complex with up to four water molecules per unit of MIL-160(Al). Chemical kinetics of water sorption on MIL-160(Al) follows a pseudo-first order rate law and it is consistent with dynamics and timescale revealed by in-situ time-dependent ATR-FTIR. The combination of two in-situ time-dependent methods, the ATR-FTIR spectroscopy and gravimetry, forms a new powerful experimental approach to facilely study mechanisms, stoichiometry and chemical kinetics of various solid-gas reactions in the ambient and controlled environments.

Coordination-Induced Band Gap Reduction in a Metal-Organic Framework

Herein, we report on the synthesis of a microporous, three-dimensional phosphonate metal-organic framework (MOF) with the composition Cu3 (H5 -MTPPA)2  ⋅ 2 NMP (H8 -MTPPA=methane tetra-p-phenylphosphonic acid and NMP=N-methyl-2-pyrrolidone). This MOF, termed TUB1, has a unique one-dimensional inorganic building unit composed of square planar and distorted trigonal bipyramidal copper atoms. It possesses a (calculated) BET surface area of 766.2 m2 /g after removal of the solvents from the voids. The Tauc plot for TUB1 yields indirect and direct band gaps of 2.4 eV and 2.7 eV, respectively. DFT calculations reveal the existence of two spin-dependent gaps of 2.60 eV and 0.48 eV for the alpha and beta spins, respectively, with the lowest unoccupied crystal orbital for both gaps predominantly residing on the square planar copper atoms. The projected density of states suggests that the presence of the square planar copper atoms reduces the overall band gap of TUB1, as the beta-gap for the trigonal bipyramidal copper atoms is 3.72 eV.

Cracking the immune fingerprint of metal-organic frameworks

The human body is in a never-ending chess game against pathogens. When the immune system, our natural defence tool, is weakened, these organisms are able to escape, overcoming the body's contingency plan, which results in the body going into a pathological state. To overcome this checkmate status, emerging nanomedicines have been successfully employed as one of the best tactics for boosting the immune response, manipulating the body's defence tools for the specific recognition/elimination of pathological cells via the active ingredient delivery. However, the vast majority of these drug-delivery systems (DDS) are considered to be exclusively passive vehicles, with nanoscale metal-organic frameworks (nanoMOFs) attracting a great deal of attention due to their versatility and ability to carry and deliver exceptional drug payloads and to modulate their biological bypass. Nonetheless, their intrinsic immunogenicity character has been never addressed. Considering the immense possibilities that nanoMOFs offer as a treatment platform, the present study aimed to unveil the immunological fingerprint of MOFs, including an in-deep evaluation of the cellular oxidation balance, the inflammation and recruitment of immune cells and the precise Th1/Th2 cytokine profile that is triggered. This study aims to gain insights that will make more feasible the design of customized immune-active MOF nanoplatforms according to targeted diseases, as the next ace up immune system sleeve.