Synthesis and Functionalization of Porous Zr-Diaminostilbenedicarboxylate Metal-Organic Framework for Storage and Stable Delivery of Ibuprofen

Functionalization of a porous copper(ii) metal-organic framework and its capacity for loading and delivery of ibuprofen

A porous copper(ii) metal-organic framework (MOF) of 4,4',4''-tri-tert-butyl-2,2':6',2''-terpyridine(N3ttb) and 5-nitroisophthalic acid (npd) formulated as [Cu(npd)(N3ttb)]·(DMF)(H2O) 1 (DMF = dimethylformamide) was synthesized and characterized by elemental analyses, spectroscopic techniques, single crystal X-ray crystallography, and scanning electron microscopy. Single crystal X-ray crystallographic analysis of the copper(ii) metal-organic framework reveals a monoclinic crystal system with space group P21/c. The copper(ii) ion is in a five-coordinate geometry consisting of three meridional nitrogen atoms of 4,4',4''-tri-tert-butyl-2,2':6',2''-terpyridine and two oxygen atoms of 5-nitroisophthalic acid to form a square pyramidal structure. The compound was functionalized with ethylenediamine (ED) to form [Cu(npd)(N3ttb)]-ED 2 that was characterized by FT-IR, PXRD, SEM-EDX and BET and the drug loading capacity was investigated and compared with that of as-synthesized MOFs. The amount of ibuprofen loaded was 916.44 mg g-1 (15.27%) & 1530.20 mg g-1 (25.50%) over 1 and 2, respectively. The results indicate that the functionalized MOFs 2 have a higher loading capacity for ibuprofen than 1 by 613.76 mg g-1 (10.23%), which could be ascribed to the acid-base interactions in the functionalized molecules. The results show that [Cu(npd)(N3ttb)]-ED 2 is a better drug transporter than [Cu(npd)(N3ttb)]·(DMF)(H2O) 1 due to the presence of an amine functional group that interacts with the acid group on the ibuprofen through non-covalent bonds interactions.

Effects of Fluorinated Functionalization of Linker on Quercetin Encapsulation, Release and Hela Cell Cytotoxicity of Cu-Based MOFs as Smart pH-Stimuli Nanocarriers

Controlled delivery of target molecules is required in many medical and chemical applications. For such purposes, metal-organic frameworks (MOFs), which possess desirable features such as high porosity, large surface area, and adjustable functionalities, hold great potential as drug carriers. Herein, Quercetin (QU), as an anticancer drug, was loaded on Cu2 (BDC)2 (DABCO) and Cu2 (F4 BDC)2 )DABCO) MOFs (BDC=1,4-benzenedicarboxylate and DABCO=1,4-diazabicyclo[2.2.2]octane). As these Cu-MOFs have a high surface area, an appropriate pore size, and biocompatible ingredients, they can be utilized to deliver QU. The loading efficiency of QU in these MOFs was 49.5 % and 41.3 %, respectively. The drug-loaded compounds displayed sustained drug release over 15 days, remarkably high drug loading capacities and pH-controlled release behavior. The prepared nanostructures were characterized by different characterization technics including FT-IR, PXRD, ZP, TEM, FE-SEM, UV-vis, and BET. In addition, MTT assays were carried out on the HEK-293 and HeLa cell lines to investigate cytotoxicity. Cellular apoptosis analysis was performed to investigate the cell death mechanisms. Grand Canonical Monte Carlo simulations were conducted to analyze the interactions between MOFs and QU. Moreover, the stability of MOFs was also investigated during and after the drug release process. Ultimately, kinetic models of drug release were evaluated.

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.

Green and facile synthesis of lignin/HKUST-1 as a novel hybrid biopolymer metal-organic-framework for a pH-controlled drug release system

This manuscript describes the synthesis and characterization of a hybrid polymer/HKUST-1 composite for oral drug delivery. A green, one-pot approach was employed to synthesize the modified metal-organic frameworks (MOFs) composite using alkali lignin as a novel pH-responsive biopolymer carrier for the simulated oral delivery system. Several analytical techniques, including Fourier transform infrared (FTIR), X-ray powder diffraction (XRPD), Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) were used to analyze the chemical and crystalline structure of HKUST-1 and L/HKUST-1 composite. The drug loading capacity and drug-controlled release behavior of HKUST-1 and L/HKUST-1 were examined using ibuprofen (IBU) as an oral drug model. L/HKUST-1 composite demonstrated a pH-controlled drug release behavior by advancing the drug stability at low pHs such as the gastric medium and controlling drug release in the pH range of 6.8-7.4, similar to intestinal pH. The results suggest that the L/HKUST-1 composite is a promising candidate for oral medication delivery.

Stabilization of Palladium-Nanoparticle-Decorated Postsynthesis-Modified Zr-UiO-66 MOF as a Reusable Heterogeneous Catalyst in C-C Coupling Reaction

Here we prepared a highly efficient and reusable catalyst by a step-by-step postsynthesis modification of UiO-66-NH2 metal-organic frameworks (MOFs) with nitrogen-rich organic ligands and used it as support for the preparation of UiO-66-NH2@cyanuric chloride@2-aminopyrimidine/PdNPs. The catalytic performance's results of UiO-66-NH2@cyanuric chloride@2-aminopyrimidine/PdNPs, UiO-66-NH2/PdNPs, and UiO-66-NH2@cyanuric chloride/PdNPs indicate high efficiency of the modulation of the microenvironment of the palladium NPs. The addition of N-rich organic ligands through postsynthesis modification caused a unique structure of the final composite in favor of the progress of the C-C coupling reaction. Various techniques, including FT-IR, XRD, SEM, TEM, EDS, and elemental mapping, were used to characterize UiO-66-NH2@cyanuric chloride@2-aminopyrimidine/PdNPs, indicating its successful preparation. Three C-C coupling reactions, including the Suzuki, Heck, and Sonogashira coupling reactions, were promoted using the produced catalyst. As a result of the postsynthesis modification (PSM), the proposed catalyst displays improved catalytic performance. In addition, the suggested catalyst was highly recyclable up to ten times without leaching of PdNPs.

Research on Improved MOF Materials Modified by Functional Groups for Purification of Water

With the rapid development of urbanization and industrialization, water contamination has gradually become a big problem. Relevant studies show that adsorption is an efficient strategy to treat pollutants in water. MOFs are a class of porous materials with a three-dimensional frame structure shaped by the self-assembly of metal centers and organic ligands. Because of its unique performance advantages, it has become a promising adsorbent. At present, single MOFs cannot meet the needs, but the introduction of familiar functional groups on MOFs can promote the adsorption performance of MOFs on the target. In this review, the main advantages, adsorption mechanism, and specific applications of various functional MOF adsorbents for pollutants in water are reviewed. At the end of the article, we summarize and discuss the future development direction.

Synthesis, Characterization, and Application of Magnetized Lanthanum (III)-Based Metal-Organic Framework for the Organic Dye Removal from Water

A hybrid composite based on metal-organic framework (MOF) was chemically fabricated by embedding the magnetic Fe3O4 nanoparticles within amino-functionalized porous La-MOF (MOF/NH2) to produce a highly efficient and reusable composite of MOF/NH2/Fe3O4. Different proper techniques were used for the characterization of surface morphology and chemical arrangement of the prepared MOF/NH2/Fe3O4 composite. The characterization results using various techniques including Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer, Emmett, and Teller analysis (BET), and vibrating sample magnetometer (VSM) approved the successful fabrication of MOF with amino arms on its surface besides the well magnetization using magnetic nanoparticles. The MOF/NH2/Fe3O4 composite showed enhanced adsorption capacity (618 mg/g) toward methyl orange (MO) anionic dye which is higher than many commercial reported adsorbents due to the presence of many types of adsorption sites (NH2 groups and lanthanum sites), large surface area of MOF, and the synergetic effect of magnetic nanoparticles. Moreover, the MOF/NH2/Fe3O4 composite showed selective adsorption of MO dye from dye mixtures owing to the electrostatic attraction. Also, the MOF/NH2/Fe3O4 composite retained over 90% of its efficiency for the dye removal even after six successive cycles. So, the present study provided a practical strategy for the design of functional MOF hybrid composites. Furthermore, due to the adaptability of its architectural form, it is a potential adsorbent material for industrial wastewater treatment uses.

Enhanced Oral NO Delivery through Bioinorganic Engineering of Acid-Sensitive Prodrug into a Transformer-like DNIC@MOF Microrod

Nitric oxide (NO) is an endogenous gasotransmitter regulating alternative physiological processes in the cardiovascular system. To achieve translational application of NO, continued efforts are made on the development of orally active NO prodrugs for long-term treatment of chronic cardiovascular diseases. Herein, immobilization of NO-delivery [Fe₂(μ-SCH₂CH₂COOH)₂(NO)₄] (DNIC-2) onto MIL-88B, a metal-organic framework (MOF) consisting of biocompatible Fe³⁺ and 1,4-benzenedicarboxylate (BDC), was performed to prepare a DNIC@MOF microrod for enhanced oral delivery of NO. In simulated gastric fluid, protonation of the BDC linker in DNIC@MOF initiates its transformation into a DNIC@tMOF microrod, which consisted of DNIC-2 well dispersed and confined within the BDC-based framework. Moreover, subsequent deprotonation of the BDC-based framework in DNIC@tMOF under simulated intestinal conditions promotes the release of DNIC-2 and NO. Of importance, this discovery of transformer-like DNIC@MOF provides a parallel insight into its stepwise transformation into DNIC@tMOF in the stomach followed by subsequent conversion into molecular DNIC-2 in the small intestine and release of NO in the bloodstream of mice. In comparison with acid-sensitive DNIC-2, oral administration of DNIC@MOF results in a 2.2-fold increase in the oral bioavailability of NO to 65.7% in mice and an effective reduction of systolic blood pressure (SBP) to a ΔSBP of 60.9 ± 4.7 mmHg in spontaneously hypertensive rats for 12 h.

Anti-inflammatory and antioxidant effects of nanoformulations composed of metal-organic frameworks delivering rutin and/or piperine natural agents

Plant-derived natural medicines have been extensively studied for anti-inflammatory or antioxidant properties, but challenges to their clinical use include low bioavailability, poor solubility in water, and difficult-to-control release kinetics. Nanomedicine may offer innovative solutions that can enhance the therapeutic activity and control release kinetics of these agents, opening the way to translating them into the clinic. Two agents of particular interest are rutin (Ru), a flavonoid, and piperine (Pip), an alkaloid, which exhibit a range of pharmacological activities that include antioxidant and anti-inflammatory effects. In this work, nanoformulations were developed consisting of two metal–organic frameworks (MOFs) with surface modifications, Ti-MOF and Zr-MOF, each of them loaded with Ru and/or Pip. Both MOFs and nanoformulations were characterized and evaluated in vivo for anti-inflammatory and antioxidant effects. Loadings of ∼17 wt.% for a single pro-drug and ∼27 wt.% for dual loading were achieved. The release patterns for Ru and or Pip followed two stages: a zero-order for the first 12-hour stage, and a second stage of stable sustained release. At pH 7.4, the release patterns best fit to zero-order and Korsmeyer–Peppas kinetic models. The nanoformulations had enhanced anti-inflammatory and antioxidant effects than any of their elements singly, and those with Ru or Pip alone showed stronger effects than those with both agents. Results of assays using a paw edema model, leukocyte migration, and plasma antioxidant capacity were in agreement. Our preliminary findings indicate that nanoformulations with these agents exert better anti-inflammatory and antioxidant effects than the agents in their free form.

Adsorptive removal of hazardous organics from water and fuel with functionalized metal-organic frameworks: Contribution of functional groups

The purification of contaminated water and fuel is very important for our sustainability. Adsorptive removal has attracted significant attention because of possible applications in industry and the rapid development of metal-organic frameworks (MOFs), which can be competitive adsorbents. In this review, the possible/competitive purification of water (contaminated with organics) and fuel (composed of S- and N-Containing compounds) via adsorption using MOFs, especially those with various functional groups (FGs), will be discussed. The contribution of FGs such as -OH, -COOH, -SO₃H, -NH₂, and -NH₃⁺ to adsorption/purification will be analyzed in detail, not only to understand the plausible adsorption mechanism but also to utilize specific FGs in adsorption. Moreover, methods for introducing FGs onto MOFs will be summarized. Finally, the prospects for both adsorption/removal and emerging fields will be suggested. Studies for practical applications in industry with shaped MOFs from inexpensive route will be important. The solution pH should be considered for the adsorption of aqueous solution. Applications of MOFs in other fields like storage/delivery and enrichment of analytes might be deeply studied.

Alkali complexes of non-steroidal anti-inflammatory drugs inhibit lung and oral cancers in vitro

Alkali metal complexes (Li, K, and Cs) displayed excellent activities against oral and lung cancer cells with the least toxicity toward normal cells.