Recent Advances in Metal-Organic-Framework-Based Nanocarriers for Controllable Drug Delivery and Release

Enhanced targeted drug delivery to hepatocellular carcinoma using Cucurbit[6]uril-modified ZIF-8 nanoparticle

Building on our innovative approach to combatting cancer, this study explores the development of a sophisticated hybrid nanocarrier system leveraging the unique properties of allyl oxide cucurbit[6]uril with galactose clusters (AOQ[6]@Gal) to modify ZIF-8 nanoparticles. These nanoparticles are designed to encapsulate and efficiently deliver the anticancer drugs doxorubicin (DOX) and curcumin (CUR), enhancing their water solubility and stability, while also providing active targeting towards hepatocellular carcinoma cells. The comprehensive characterization of AOQ[6]@Gal@ZIF-8@Drug nanoparticles revealed promising outcomes, including drug loading efficiencies of 9.7% for DOX and 8.3% for CUR, alongside a pH-responsive release profile that ensures effective drug delivery in the tumor microenvironment. Cytotoxicity studies underscored the hybrid system's superior safety profile, exhibiting minimal toxicity towards normal hepatocytes HL7702 and pronounced cytotoxic effects against hepatocellular carcinoma cells HepG2. These results highlight the hybrid nanocarrier's potential as a targeted, efficient, and safe platform for the delivery of chemotherapy agents in the treatment of liver cancer.

A glutathione-activated bismuth-gallic acid metal-organic framework nano-prodrug for enhanced sonodynamic therapy of breast tumor

Sonodynamic therapy is a promising, noninvasive, and precise tumor treatment that leverages sonosensitizers to generate cytotoxic reactive oxygen species during ultrasound stimulation. Gallic acid (GA), a natural polyphenol, possesses certain anti-tumor properties, but exhibits significant toxicity toward normal cells, limiting its application in cancer treatment. To overcome this issue, we synthesized a bismuth-gallic acid (BGA), coordinated metal-organic framework (MOF) nano-prodrug. Upon encountering glutathione (GSH), BGA gradually dissociated and depleted GSH, releasing GA, which had anti-tumor effects. As an MOF with semiconductor properties, BGA primarily produced superoxide anion radical upon ultrasound excitation. After the release of GA, GA generated superoxide anion radical and further produced high toxic singlet oxygen under ultrasound stimulation, while further oxidizing and consuming GSH, enhancing sonocatalytic performance. Additionally, the released GA induced cell cycle arrest, ultimately leading to apoptosis. Our results revealed that BGA, as a GSH-activated, metal-polyphenol MOF nano-prodrug, showed potential for use in breast tumor sonodynamic therapy, providing a novel strategy for precise tumor treatment.

Multifunctional metal-organic frameworks as promising nanomaterials for antimicrobial strategies

Bacterial infections pose a serious threat to human health. While antibiotics have been effective in treating bacterial infectious diseases, antibiotic resistance significantly reduces their effectiveness. Therefore, it is crucial to develop new and effective antimicrobial strategies. Metal-organic frameworks (MOFs) have become ideal nanomaterials for various antimicrobial applications due to their crystalline porous structure, tunable size, good mechanical stability, large surface area, and chemical stability. Importantly, the performance of MOFs can be adjusted by changing the synthesis steps and conditions. Pure MOFs can release metal ions to modulate cellular behaviors and kill various microorganisms. Additionally, MOFs can act as carriers for delivering antimicrobial agents in a desired manner. Importantly, the performance of MOFs can be adjusted by changing the synthesis steps and conditions. Furthermore, certain types of MOFs can be combined with traditional photothermal or other physical stimuli to achieve broad-spectrum antimicrobial activity. Recently an increasing number of researchers have conducted many studies on applying various MOFs for diseases caused by bacterial infections. Based on this, we perform this study to report the current status of MOF-based antimicrobial strategy. In addition, we also discussed some challenges that MOFs currently face in biomedical applications, such as biocompatibility and controlled release capabilities. Although these challenges currently limit their widespread use, we believe that with further research and development, new MOFs with higher biocompatibility and targeting capabilities can provide diversified treatment strategies for various diseases caused by bacterial infections.

Metal compounds as antimicrobial agents: 'smart' approaches for discovering new effective treatments

Due to their considerable chemical diversity, metal compounds are attracting increasing and renewed attention from the scientific and medical communities as potential antimicrobial agents to combat the growing problem of antibiotic resistance. The development of metal compounds as antimicrobial agents typically follows classical drug discovery procedures and suffers from the same problems; indeed, these procedures can be very expensive and time-consuming, and carry an intrinsically high risk of failure. Here, we show how some established drug discovery approaches can be conveniently and successfully applied to antimicrobial metal compounds to provide some shortcuts for faster clinical translation of new treatments. Specifically, we refer to (i) drug repurposing, (ii) drug combination and (iii) drug targeting by bioconjugation; some relevant examples will be illustrated.

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.

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.

Recent advances in carbon quantum dots for gene delivery: A comprehensive review

Gene therapy is a revolutionary technology in healthcare that provides novel therapeutic options and has immense potential in addressing genetic illnesses, malignancies, and viral infections. Nevertheless, other obstacles still need to be addressed regarding safety, ethical implications, and technological enhancement. Nanotechnology and gene therapy fields have shown significant promise in transforming medical treatments by improving accuracy, effectiveness, and personalization. This review assesses the possible uses of gene therapy, its obstacles, and future research areas, specifically emphasizing the creative combination of gene therapy and nanotechnology. Nanotechnology is essential for gene delivery as it allows for the development of nano-scale carriers, such as carbon quantum dots (CQDs), which may effectively transport therapeutic genes into specific cells. CQDs exhibit distinctive physicochemical characteristics such as small size, excellent stability, and minimal toxicity, which render them highly favorable for gene therapy applications. The objective of this study is to review and describe the current advancements in the utilization of CQDs for gene delivery. Additionally, it intends to assess existing research, explore novel applications, and identify future opportunities and obstacles. This study offers a thorough summary of the current state and future possibilities of using CQDs for gene delivery. Combining recent research findings highlights the potential of CQDs to revolutionize gene therapy and its delivery methods.

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.

Incorporating mannose-functionalized hydroxyapatite/metal-organic framework into the hyaluronic acid hydrogel film: A potential dual-targeted oral anticancer delivery system

The recent challenge in enhancing the targeted delivery of anticancer drugs to cancer cells is improving the bioavailability and therapeutic efficacy of drug delivery systems while minimizing their systemic side effects. In this study, the MIL-88(Fe) metal-organic framework was synthesized using the in situ method in the presence of hydroxyapatite nanoparticles (HAP) toward the HAP/MIL-88(Fe) (HM) nanocomposite preparation. It was then functionalized with mannose (M) as an anticancer receptor through the Steglich esterification method. Various analyses confirmed the successful synthesis of MHM. For drug release investigation, 5-Fu was loaded into the MHM, which was then coated with a hyaluronic acid (HA) hydrogel film. Characterization analyses verified the structure of the resulting HA/5-Fu-MHM hydrogel film. In vitro drug release experiments showed that the release of 5-Fu drug from HA/5-Fu-MHM could be controlled with pH, reducing its release rate in the acidic environment of the stomach while increasing it in the intestinal environment. Cytotoxicity results of the HA/5-Fu-MHM hydrogel film against HT29 cancer cells showed enhanced cytotoxicity due to the mannose and hyaluronic acid in its structure, which triggers a dual-targeted drug delivery system. The obtained results indicate that the prepared hydrogel films can be a promising bio-platform for colon cancer treatment.

Effective strategies to enhance the diagnosis and treatment of RCC: The application of biocompatible materials

Renal cell carcinoma (RCC) is recognized as one of the three primary malignant tumors affecting the urinary system, posing a significant risk to human health and life. Despite advancements in understanding RCC, challenges persist in its diagnosis and treatment, particularly in early detection and diagnosis due to issues of low specificity and sensitivity. Consequently, there is an urgent need for the development of effective strategies to enhance diagnostic accuracy and treatment outcomes for RCC. In recent years, with the extensive research on materials for applications in the biomedical field, some materials have been identified as promising for clinical applications, e.g., in the diagnosis and treatment of many tumors, including RCC. Herein, we summarize the latest materials that are being studied and have been applied in the early diagnosis and treatment of RCC. While focusing on their adjuvant effects, we also discuss their technical principles and safety, thus highlighting the value and potential of their application. In addition, we also discuss the limitations of the application of these materials and possible future directions, providing new insights for improving RCC diagnosis and treatment.

Copper(II)-Based Nano-Regulator Correlates Cuproptosis Burst and Sequential Immunogenic Cell Death for Synergistic Cancer Immunotherapy

Immunogenic cell death (ICD) of tumor cells serves as a crucial initial signal in the activation of anti-tumor immune responses, holding marked promise in the field of tumor immunotherapy. However, low immunogenicity tumors pose challenges in achieving complete induction of ICD, thereby limiting the response rates of immunotherapy in clinical patients. The emergence of cuproptosis as a new form of regulated cell death has presented a promising strategy for enhanced immunotherapy of low immunogenic tumors. To trigger cuproptosis, copper-ionophore elesclomol (ES) had to be employed for the copper-transporting-mediated process. Herein, we proposed a copper(II)-based metal-organic framework nanoplatform (Cu-MOF) to facilitate a cooperative delivery of encapsulated ES and copper (ES-Cu-MOF) to induce cuproptosis burst and enhance ICD of fibrosarcoma. Our results showed that the ES-Cu-MOF nano-regulator could effectively release Cu2+ and ES in response to the intracellular environment, resulting in elevated mitochondrial ROS generation and initiated cuproptosis of tumor cells. Furthermore, sequential ICDs were significantly triggered via the ES-Cu-MOF nano-regulator to activate the anti-tumor immune response. The results of tumor inhibition experiment indicated that the nano-regulator of ES-Cu-MOF obviously accumulated in the tumor site, inducing ICD for dendritic cell activation. This enabled an increased infiltration of cytotoxic CD8+ T cells and consequently enhanced antitumor immune responses for successfully suppressing fibrosarcoma growth. Thus, the copper(II)-based metal-organic framework nano-regulator offered a promising approach for inducing cuproptosis and cuproptosis-stimulated ICD for cancer immunotherapy.

MOFs for next-generation cancer therapeutics through a biophysical approach-a review

Metal-organic frameworks (MOFs) have emerged as promising nanocarriers for cancer treatment due to their unique properties. Featuring high porosity, extensive surface area, chemical stability, and good biocompatibility, MOFs are ideal for efficient drug delivery, targeted therapy, and controlled release. They can be designed to target specific cellular organelles to disrupt metabolic processes in cancer cells. Additionally, functionalization with enzymes mimics their catalytic activity, enhancing photodynamic therapy and overcoming apoptosis resistance in cancer cells. The controllable and regular structure of MOFs, along with their tumor microenvironment responsiveness, make them promising nanocarriers for anticancer drugs. These carriers can effectively deliver a wide range of drugs with improved bioavailability, controlled release rate, and targeted delivery efficiency compared to alternatives. In this article, we review both experimental and computational studies focusing on the interaction between MOFs and drug, explicating the release mechanisms and stability in physiological conditions. Notably, we explore the relationship between MOF structure and its ability to damage cancer cells, elucidating why MOFs are excellent candidates for bio-applicability. By understanding the problem and exploring potential solutions, this review provides insights into the future directions for harnessing the full potential of MOFs, ultimately leading to improved therapeutic outcomes in cancer treatment.

Synergistic applications of cyclodextrin-based systems and metal-organic frameworks in transdermal drug delivery for skin cancer therapy

This review article explores the innovative field of eco-friendly cyclodextrin-based coordination polymers and metal-organic frameworks (MOFs) for transdermal drug delivery in the case of skin cancer therapy. We critically examine the significant advancements in developing these nanocarriers, with a focus on their unique properties such as biocompatibility, targeted drug release, and enhanced skin permeability. These attributes are instrumental in addressing the limitations inherent in traditional skin cancer treatments and represent a paradigm shift towards more effective and patient-friendly therapeutic approaches. Furthermore, we discuss the challenges faced in optimizing the synthesis process for large-scale production while ensuring environmental sustainability. The review also emphasizes the immense potential for clinical applications of these nanocarriers in skin cancer therapy, highlighting their role in facilitating targeted, controlled drug release which minimizes systemic side effects. Future clinical applications could see these nanocarriers being customized to individual patient profiles, potentially revolutionizing personalized medicine in oncology. With further research and clinical trials, these nanocarriers hold the promise of transforming the landscape of skin cancer treatment. With this study, we aim to provide a comprehensive overview of the current state of research in this field and outline future directions for advancing the development and clinical application of these innovative nanocarriers.

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

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

Romanian Wild-Growing Chelidonium majus-An Emerging Approach to a Potential Antimicrobial Engineering Carrier System Based on AuNPs: In Vitro Investigation and Evaluation

Novel nanotechnology based on herbal products aspires to be a high-performing therapeutic platform. This study reports the development of an original engineering carrier system that jointly combines the pharmacological action of Chelidonium majus and AuNPs, with unique properties that ensure that the limitations imposed by low stability, toxicity, absorption, and targeted and prolonged release can be overcome. The metabolite profile of Romanian wild-grown Chelidonium majus contains a total of seventy-four phytochemicals belonging to eight secondary metabolite categories, including alkaloids, amino acids, phenolic acids, flavonoids, carotenoids, fatty acids, sterols, and miscellaneous others. In this study, various techniques (XRD, FTIR, SEM, DLS, and TG/DTG) were employed to investigate his new carrier system's morpho-structural and thermal properties. In vitro assays were conducted to evaluate the antioxidant potential and release profile. The results indicate 99.9% and 94.4% dissolution at different pH values for the CG-AuNPs carrier system and 93.5% and 85.26% for greater celandine at pH 4 and pH 7, respectively. Additionally, three in vitro antioxidant assays indicated an increase in antioxidant potential (flavonoid content 3.8%; FRAP assay 24.6%; and DPPH 24.4%) of the CG-AuNPs carrier system compared to the herb sample. The collective results reflect the system's promising perspective as a new efficient antimicrobial and anti-inflammatory candidate with versatile applications, ranging from target delivery systems, oral inflammation (periodontitis), and anti-age cosmetics to extending the shelf lives of products in the food industry.

Tuning the mechanical properties of sol-gel monolithic metal-organic frameworks by ligand engineering

The sol-gel monolithic MOFs has come to prominent attention for industrial application owing to the higher powder packing density, enhanced processabilities and mechanical stabilities compared to the powder counterpart. The mechanical properties are particularly important during machine shaping processing because of porous framework structure. We used ligand engineering to design and synthesize monoUiO-66-type materials modified different chemical functional groups (-NH2, -2OH, -2COOH) by sol-gel method, with the aim to assess the impact of different functional groups on the mechanical properties of these monolithic materials based on nanoindentation technology. We observe larger mass and sterically bulky functional groups (-2COOH) can significantly decrease the BET areas and pore volume of monoUiO-66 through N2 adsorption isotherms at 77 K. Hence, the two -COOH groups modified monoUiO-66 tends to exhibit the higher H of 0.589 ± 0.018 GPa and E of 15.471 ± 0.250 GPa compared with monoUiO-66 modified with -NH2 (0.334 ± 0.009 GPa/11.959 ± 0.243 GPa) and -2OH (0.331 ± 0.008 GPa/10.251 ± 0.142 GPa) groups. The creep indentation tests and the jump indentation tests further demonstrate the modification by larger functional groups -COOH on monoUiO-66 could resist irreversible plastic deformation. Furthermore, the monoUiO-66-(COOH)2 has significantly smaller the activation volume of 0.34 ∼ 0.43 nm3, highlighting the introduction of -COOH groups reduced the pore volume and restrict the number of pores involved in one collapse event. Our results demonstrate the larger mass and sterically bulky functional groups have significant influence on the mechanical properties of the monoMOFs materials.

Copper release by MOF-74(Cu): a novel pharmacological alternative to diseases with deficiency of a vital oligoelement

Copper deficiency can trigger various diseases such as Amyotrophic Lateral Sclerosis (ALS), Parkinson's disease (PD) and even compromise the development of living beings, as manifested in Menkes disease (MS). Thus, the regulated administration (controlled release) of copper represents an alternative to reduce neuronal deterioration and prevent disease progression. Therefore, we present, to the best of our knowledge, the first experimental in vitro investigation for the kinetics of copper release from MOF-74(Cu) and its distribution in vivo after oral administration in male Wistar rats. Taking advantage of the abundance and high periodicity of copper within the crystalline-nanostructured metal-organic framework material (MOF-74(Cu)), it was possible to control the release of copper due to the partial degradation of the material. Thus, we simultaneously corroborated a low accumulation of copper in the liver (the main detoxification organ) and a slight increase of copper in the brain (striatum and midbrain), demonstrating that MOF-74(Cu) is a promising pharmacological alternative (controlled copper source) to these diseases.

Magnetic nanocomposite through coating mannose-functionalized metal-organic framework with biopolymeric pectin hydrogel beads: A potential targeted anticancer oral delivery system

This study designed magnetic nanocomposite hydrogel beads for a potential targeted anticancer oral delivery system. To end this, nanohybrids of Fe3O4/MIL-88(Fe) (FM) were synthesized through in-situ method by the treatment of terephthalic acid (TPA) and (Fe(NO3)3·9H2O) in the presence of Fe3O4 nanoparticles. They were then modified with mannose sugar as an anticancer receptor to achieve a targeted drug delivery system. After loading methotrexate (MTX), they were coated with pH-sensitive pectin hydrogel beads in the presence of a calcium chloride crosslinker for possible transferring the nanohybrids to the intestine through the acidic environment of the digestive system. The results of different analysis techniques showed that the materials were properly synthesized, coated, and loaded. The designed magnetic nanocomposite hydrogel beads showed pH-sensitive swelling and drug release rate, protecting MTX from the acidic environment of the stomach. MTT test revealed a good cytotoxicity toward colon cancer HT29 cell lines. Remarkably, the functionalization of MTX-loaded FM nanohybrids with mannose (MTX-MFM) enhanced their anticancer properties up to about 20 %. The results recommended that the prepared novel magnetic nanocomposite hydrogel beads have a good potential to be used as a targeted anticancer oral delivery system.

Combining emulsion electrospinning with surface functionalization to fabricate multistructural PLA/CS@ZIF-8 nanofiber membranes toward pH-responsive dual drug delivery

Developing of the multifunctional polymeric carrier for controlled drug release is still one of most challenging task. In this work, a pH-responsive dual drug delivery system was designed and prepared based on the zeolitic imidazolate framework-8 (ZIF-8). The poly(lactic acid)/chitosan (PLA/CS) core-shell nanofiber membranes by emulsion electrospinning, which the hydrophilic drug (Astragalus Polysacharin, APS) was encapsulated in the CS core and the hydrophobic drug (Camptothecin, CPT) was loaded into the PLA shell, respectively. Subsequently, ZIF-8 nanoparticles served as the protective layer were immobilized on the surface of PLA/CS to form multi-structural PLA/CS@ZIF-8 nanofiber membranes. In vitro drug release of nanofiber membranes were studied in the acidic and neutral medium, respectively. The results were that the hydrophilicity and surface roughness of nanofiber membranes rose with increasing of 2-MIM concentrations. The nanofiber membranes also had excellent pH-responsive and controlled release property. Furthermore, the drug release of PLA/CS@ZIF-8 for either APS or CPT were all carried out in a coexisting manner of diffusion and skeleton corrosion. In addition, in vitro cytotoxicity assay indicated nanofiber membranes with good cytocompatibility. Therefore, the multi-structured PLA/CS@ZIF-8 nanofiber membranes has been used as a potential pH-responsive dual drug release system.

Advances and prospects of tumor immunotherapy mediated by immune cell-derived biomimetic metal-organic frameworks

The clinical translational success of nanomedicine and immunotherapy has already proved the immense potential in the field of nanotechnology and immunization. However, the development of nanomedicine is confronted with challenges such as potential toxicity and unclear nano-bio interactions. The efficacy of immunotherapy is limited to only a few groups. Combining immunotherapy with nanomedicine for multi-modal treatment effectively compensates for the limitations of the above single therapy. Immune cell membrane camouflaged metal-organic frameworks (ICM-MOFs) have emerged as a simple yet promising multimodal treatment strategy that possess multifunctional nanoscale properties and exhibit immune cell-like behaviors of stealth, targeting and immunomodulation. Here, we comprehensively discuss the latest advancements in ICM-MOFs, with a focus on the challenges of mono-immunotherapy, the superiority of biomimetic coating for MOF functionalization, preparation methods, related action mechanisms and biomedical applications. Finally, we address the challenges and prospects for clinical translation.

Performance of Zr-Based Metal-Organic Framework Materials as In Vitro Systems for the Oral Delivery of Captopril and Ibuprofen

Zr-based metal-organic framework materials (Zr-MOFs) with increased specific surface area and pore volume were obtained using chemical (two materials, Zr-MOF1 and Zr-MOF3) and solvothermal (Zr-MOF2) synthesis methods and investigated via FT-IR spectroscopy, TGA, SANS, PXRD, and SEM methods. The difference between Zr-MOF1 and Zr-MOF3 lies in the addition of reactants during synthesis. Nitrogen porosimetry data indicated the presence of pores with average dimensions of ~4 nm; using SANS, the average size of the Zr-MOF nanocrystals was suggested to be approximately 30 nm. The patterns obtained through PXRD were characterized by similar features that point to well-crystallized phases specific for the UIO-66 type materials; SEM also revealed that the materials were composed of small and agglomerate crystals. Thermogravimetric analysis revealed that both materials had approximately two linker deficiencies per Zr6 formula unit. Captopril and ibuprofen loading and release experiments in different buffered solutions were performed using the obtained Zr-based metal-organic frameworks as drug carriers envisaged for controlled drug release. The carriers demonstrated enhanced drug-loading capacity and showed relatively good results in drug delivery. The cumulative percentage of drug release in phosphate-buffered solution at pH 7.4 was higher than that in buffered solution at pH 1.2. The release rate could be controlled by changing the pH of the releasing solution. Different captopril release behaviors were observed when the experiments were performed using a permeable dialysis membrane.

An updated review on oral protein-based antigen vaccines efficiency and delivery approaches: a special attention to infectious diseases

Various infectious agents affect human health via the oral entrance. The majority of pathogens lack approved vaccines. Oral vaccination is a convenient, safe and cost-effective approach with the potential of provoking mucosal and systemic immunity and maintaining individual satisfaction. However, vaccines should overcome the intricate environment of the gastrointestinal tract (GIT). Oral protein-based antigen vaccines (OPAVs) are easier to administer than injectable vaccines and do not require trained healthcare professionals. Additionally, the risk of needle-related injuries, pain, and discomfort is eliminated. However, OPAVs stability at environmental and GIT conditions should be considered to enhance their stability and facilitate their transport and storage. These vaccines elicit the local immunity, protecting GIT, genital tract and respiratory epithelial surfaces, where numerous pathogens penetrate the body. OPAVs can also be manipulated (such as using specific incorporated ligand and receptors) to elicit targeted immune response. However, low bioavailability of OPAVs necessitates development of proper protein carriers and formulations to enhance their stability and efficacy. There are several strategies to improve their efficacy or protective effects, such as incorporation of adjuvants, enzyme inhibitors, mucoadhesive or penetrating devices and permeation enhancers. Hence, efficient delivery of OPAVs into GIT require proper delivery systems mainly including smart target systems, probiotics, muco-adhesive carriers, lipid- and plant-based delivery systems and nano- and microparticles.

Effect of a Zr-Based Metal-Organic Framework Structure on the Properties of Its Composite with Polyaniline

Composites of polyaniline (PANI) and Zr-based metal-organic frameworks (MOFs), UiO-66 and UiO-66-NH2, were synthesized by the oxidative polymerization of aniline in the presence of MOF templates with the MOF content in the resulting materials (78.2 and 86.7 wt %, respectively) close to the theoretical value (91.5 wt %). Scanning electron microscopy and transmission electron microscopy showed that the morphology of the composites was set by the morphology of the MOFs, whose structure was mostly preserved after the synthesis, based on the X-ray diffraction data. Vibrational and NMR spectroscopies pointed out that MOFs participate in the protonation of PANI and conducting polymer chains were grafted to amino groups of UiO-66-NH2. Unlike PANI-UiO-66, cyclic voltammograms of PANI-UiO-66-NH2 showed a well-resolved redox peak at around ≈0 V, pointing at the pseudocapacitive behavior. The gravimetric capacitance of PANI-UiO-66-NH2, normalized per mass of the active material, was also found to be higher compared to that of pristine PANI (79.8 and 50.5 F g-1, respectively, at 5 mV s-1). The introduction of MOFs into the composites with PANI significantly improved the cycling stability of the materials over 1000 cycles compared to the pristine conducting polymer, with the residual gravimetric capacitance being ≥100 and 77%, respectively. Thus, the electrochemical performance of the prepared PANI-MOF composites makes them attractive materials for application in energy storage.