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1.
Chemistry ; 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36424358

RESUMO

Countless people have been affected by the COVID-19 pandemic on a global scale. Favipiravir, has shown potential as an effective drug for SARS-CoV-2, attracting scientists' attention. However, overuse of Favipiravir easily leads to serious side effects, requiring real-time monitoring in body fluids. Given this, a new lanthanide metal organic framework (MOF) was prepared under solvothermal conditions from either Eu (Eu-MOF or (1)) or Tb (Tb-MOF or (2)) using the highly delocalized imidazoledicarboxylic acid linker H2L (H2L = 5-(4-(imidazol-1-yl) phenyl) isophthalic acid) and could be successfully applied to selective optical detection of Favipiravir. In this MOF framework, the organic linker H2L provides a high excitation energy transfer efficiency that can sensitize luminescence in lanthanides. In addition, through deliberate tuning of Eu/Tb molar ratio and reaction concentration in the lanthanide framework, ratiometric recyclable luminescent EuxTb1-x-MOF nanoparticles with open metal sites have been constructed, which present a high detection sensitivity (Ksv = 1×107 [M-1], detection limit is 4.63 nM) for Favipiravir. The detection mechanism is discussed with the help of Density Functional Theory (DFT) calculations that sheds light over the selective sensing of Favipiravir over other related COVID-19 drug candidates. Finally, to explore the practical application of Favipiravir sensing, MOF based thin films have been used for visual detection of Favipiravir and recycled 5 times.

2.
Angew Chem Int Ed Engl ; 61(43): e202211848, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36055971

RESUMO

Encapsulating ultrasmall Cu nanoparticles inside Zr-MOFs to form core-shell architecture is very challenging but of interest for CO2 reduction. We report for the first time the incorporation of ultrasmall Cu NCs into a series of benchmark Zr-MOFs, without Cu NCs aggregation, via a scalable room temperature fabrication approach. The Cu NCs@MOFs core-shell composites show much enhanced reactivity in comparison to the Cu NCs confined in the pore of MOFs, regardless of their very similar intrinsic properties at the atomic level. Moreover, introducing polar groups on the MOF structure can further improve both the catalytic reactivity and selectivity. Mechanistic investigation reveals that the CuI sites located at the interface between Cu NCs and support serve as the active sites and efficiently catalyze CO2 photoreduction. This synergetic effect may pave the way for the design of low-cost and efficient catalysts for CO2 photoreduction into high-value chemical feedstock.

3.
Int J Mol Sci ; 23(14)2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35887018

RESUMO

Nanoparticles of metal-organic frameworks (MOF NPs) are crystalline hybrid micro- or mesoporous nanomaterials that show great promise in biomedicine due to their significant drug loading ability and controlled release. Herein, we develop porous capsules from aggregate of nanoparticles of the iron carboxylate MIL-100(Fe) through a low-temperature spray-drying route. This enables the concomitant one-pot encapsulation of high loading of an antitumor drug, methotrexate, within the pores of the MOF NPs, and the collagenase enzyme (COL), inside the inter-particular mesoporous cavities, upon the formation of the capsule, enhancing tumor treatment. This association provides better control of the release of the active moieties, MTX and collagenase, in simulated body fluid conditions in comparison with the bare MOF NPs. In addition, the loaded MIL-100 capsules present, against the A-375 cancer cell line, selective toxicity nine times higher than for the normal HaCaT cells, suggesting that MTX@COL@MIL-100 capsules may have potential application in the selective treatment of cancer cells. We highlight that an appropriate level of collagenase activity remained after encapsulation using the spray dryer equipment. Therefore, this work describes a novel application of MOF-based capsules as a dual drug delivery system for cancer treatment.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Cápsulas , Sistemas de Liberação de Medicamentos , Humanos , Dietilamida do Ácido Lisérgico/análogos & derivados , Estruturas Metalorgânicas/química , Nanopartículas/química , Neoplasias/tratamento farmacológico
4.
Adv Sci (Weinh) ; 9(22): e2201494, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35666071

RESUMO

Zeolites and metal-organic frameworks (MOFs) are considered as "competitors" for new separation processes. The production of high-quality gasoline is currently achieved through the total isomerization process that separates pentane and hexane isomers while not reaching the ultimate goal of a research octane number (RON) higher than 92. This work demonstrates how a synergistic action of the zeolite 5A and the MIL-160(Al) MOF leads to a novel adsorptive process for octane upgrading of gasoline through an efficient separation of isomers. This innovative mixed-bed adsorbent strategy encompasses a thermodynamically driven separation of hexane isomers according to the degree of branching by MIL-160(Al) coupled to a steric rejection of linear isomers by the molecular sieve zeolite 5A. Their adsorptive separation ability is further evaluated under real conditions by sorption breakthrough and continuous cyclic experiments with a mixed bed of shaped adsorbents. Remarkably, at the industrially relevant temperature of 423 K, an ideal sorption hierarchy of low RON over high RON alkanes is achieved, i.e., n-hexane ≫ n-pentane ≫ 2-methylpentane > 3-methylpentane ⋙ 2,3-dimethylbutane > isopentane ≈ 2,2-dimethylbutane, together with a productivity of 1.14 mol dm-3 and a high RON of 92, which is a leap-forward compared with existing processes.

5.
Chem Asian J ; 17(13): e202200129, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35472103

RESUMO

The realization of metal-organic framework (MOF) layers onto solid surfaces is a prerequisite for their integration into devices. This work reports the direct growth of Fe3+ /benzene di-carboxylate MOFs onto functionalized silicon surfaces, compatible with a wide range of MOF synthesis conditions. The co-nucleation and growth of different crystalline phases are evidenced, whose coverage depends on the surface chemistry and/or the solution composition. Three structural phases - the cubic MIL-101(Fe), a hexagonal phase with a structure close to MOF-235 and a MIL-53(Fe) with a monoclinic symmetry - are identified through characteristic crystal shapes and their structural parameters inferred from X-Ray Diffraction. In addition to the oriented growth of 3D crystallites, the formation of two-dimensional MIL-101 nano-crystallites or thin layers/islands exhibiting extended monocrystalline domains with (111) texture is also demonstrated through high-resolution atomic force microscopy. Post-synthesis treatments reveal a weak adhesion of the hexagonal phase, indicating a different surface anchoring.

6.
Angew Chem Int Ed Engl ; 61(22): e202201924, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35266627

RESUMO

External control over the pore size of flexible metal-organic frameworks (MOFs) has recently emerged as an intriguing concept, with possible applications to gas storage and separation. In this work we present a new pressure cell capable for the first time of monitoring through in situ X-ray powder diffraction an adsorbent powder under combined uniaxial applied mechanical stress (up to 1 GPa) and gas pressure (up to 20 bar). The combined stress-pressure clamp (CSPC) cell was successfully exploited to follow the evolution of the CO2 breathing behaviour of the prototypical complex breathing MIL-53(Al) system under mechanical compression obtaining structural evidence that this MOF can be maintained in its closed pore state upon compression, precluding its re-opening at high gas pressure (>7 bar). This novel setup shows potential for the in-operando exploration of flexible systems, in equilibrium and flow configurations.

7.
Nat Commun ; 13(1): 1284, 2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35277474

RESUMO

The discovery of nanozymes for selective fragmentation of proteins would boost the emerging areas of modern proteomics, however, the development of efficient and reusable artificial catalysts for peptide bond hydrolysis is challenging. Here we report the catalytic properties of a zirconium metal-organic framework, MIP-201, in promoting peptide bond hydrolysis in a simple dipeptide, as well as in horse-heart myoglobin (Mb) protein that consists of 153 amino acids. We demonstrate that MIP-201 features excellent catalytic activity and selectivity, good tolerance toward reaction conditions covering a wide range of pH values, and importantly, exceptional recycling ability associated with easy regeneration process. Taking into account the catalytic performance of MIP-201 and its other advantages such as 6-connected Zr6 cluster active sites, the green, scalable and cost-effective synthesis, and good chemical and architectural stability, our findings suggest that MIP-201 may be a promising and practical alternative to commercially available catalysts for peptide bond hydrolysis.


Assuntos
Estruturas Metalorgânicas , Catálise , Hidrólise , Estruturas Metalorgânicas/química , Peptídeos/química , Zircônio/química
8.
Chem Soc Rev ; 51(2): 464-484, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34985082

RESUMO

In the last two decades, the field of metal-organic frameworks (MOFs) has exploded, and MOF nanoparticles in particular are being investigated with increasing interest for various applications, including gas storage and separation, water harvesting, catalysis, energy conversion and storage, sensing, diagnosis, therapy, and theranostics. To further pave their way into real-world applications, and to push the synthesis of MOF nanoparticles that are 'safe-and-sustainable-by-design', this tutorial review aims to shed light on the importance of a systematic toxicity assessment. After clarifying and working out the most important terms and aspects from the field of nanotoxicity, the current state-of-the-art of in vitro and in vivo toxicity studies of MOF nanoparticles is evaluated. Moreover, the key aspects affecting the toxicity of MOF nanoparticles such as their chemical composition, their physico-chemical properties, including their colloidal and chemical stability, are discussed. We highlight the need of more targeted synthesis of MOF nanoparticles that are 'safe-and-sustainable-by-design', and their tailored hazard assessment in the context of their potential applications in order to tap the full potential of this versatile material class in the future.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Catálise , Estruturas Metalorgânicas/toxicidade , Nanopartículas/toxicidade
11.
Materials (Basel) ; 14(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34443140

RESUMO

Li-air batteries possess higher specific energies than the current Li-ion batteries. Major drawbacks of the air cathode include the sluggish kinetics of the oxygen reduction (OER), high overpotentials and pore clogging during discharge processes. Metal-Organic Frameworks (MOFs) appear as promising materials because of their high surface areas, tailorable pore sizes and catalytic centers. In this work, we propose to use, for the first time, aluminum terephthalate (well known as MIL-53) as a flexible air cathode for Li-O2 batteries. This compound was synthetized through hydrothermal and microwave-assisted routes, leading to different particle sizes with different aspect ratios. The electrochemical properties of both materials seem to be equivalent. Several behaviors are observed depending on the initial value of the first discharge capacity. When the first discharge capacity is higher, no OER occurs, leading to a fast decrease in the capacity during cycling. The nature and the morphology of the discharge products are investigated using ex situ analysis (XRD, SEM and XPS). For both MIL-53 materials, lithium peroxide Li2O2 is found as the main discharge product. A morphological evolution of the Li2O2 particles occurs upon cycling (stacked thin plates, toroids or pseudo-spheres).

12.
Faraday Discuss ; 231(0): 326-341, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34254064

RESUMO

The potential of safe and low-cost batch production processes for Metal-Organic Frameworks (MOFs) at an industrial scale has been evaluated based on the prototypical MOF MIL-160(Al), a bio-derived material of high practical interest that can be made with a high space-time yield using green ambient pressure conditions. A simple method to calculate the production cost of this material has been determined based on a simulated process constructed with the data collected from laboratory pilot large-scale tests taking into account for the first time in MOF cost evaluation all the process parameters such as the scale, the cost of the raw materials, recirculation, and washing. The investment for a production plant established the ground for the estimation of the complete cost. The expected cost ranged from ca. 55 $ per kg at 100 tons per year down to 29.5 $ per kg for 1 kton per year production with longer term perspectives of reaching costs below 10 $ per kg once the bio-derived ligand is considered for the large-scale production of bioplastics.


Assuntos
Estruturas Metalorgânicas , Desenvolvimento Industrial
13.
Biomater Sci ; 9(16): 5407-5414, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34318804

RESUMO

Biocompatible nanoscale iron carboxylate metal-organic frameworks (nanoMOFs) have already demonstrated their ability to efficiently deliver various therapeutic molecules. The versatility of the synthesis methods and functionalization strategies could further improve their drug carrier potential. However, in oncology, preclinical evaluation still suffers from the lack of relevant models able to mimic the heterogeneity and the microenvironment of human tumors. This may impact the significance of the preclinical data, hindering the clinical translation and drug development process. Motivated by this hurdle, a 3D lung tumor model is herein developed to investigate nanoMOFs, as bare nanoparticles or coated with polyethylene glycol. Loading with doxorubicin, as a model drug, enables the investigation of their penetration capacity and efficacy in the 3D tumor nodule. NanoMOFs carry a large cargo, can diffuse efficiently within the tumor and are capable of significant intracellular penetration. Nevertheless, they prove to be therapeutically ineffective because the loaded drug is sequestrated in the lysosomal compartment and does not reach the nucleus, the doxorubicin sub-cellular target. These results question the in vivo evaluation of these nanoMOFs and call for further optimization to achieve successful drug delivery.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Humanos
14.
ACS Appl Mater Interfaces ; 13(17): 20194-20200, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33885276

RESUMO

The proton-conducting performances of a microporous Ti-based metal-organic framework (MOF), MIP-207, were successfully tuned using a multicomponent ligand replacement strategy to gradually introduce a controlled amount of sulfonic acid groups as a source of Brönsted acidic sites while keeping the robustness and ecofriendly synthesis conditions of the starting material. Typically, multivariate sulfonic-based solids MIP-207-(SO3H-IPA)x-(BTC)1-x were prepared by combining various ratios of trimesate 1,3,5-benzenetricarboxylate (BTC) moieties and 5-SO3H-isophthalate (SO3H-IPA). The best sulfonic-MOF candidate that combines structural integrity with high proton conductivity values (e.g., σ = 2.6 × 10-2 S cm-1 at 363 K/95% relative humidity) was further investigated using ab initio molecular dynamics simulations. These calculations supported that the -SO3H groups act as proton donors and revealed that the proton transfer mechanism results from the solvation structure of protons through the fast Zundel/hydronium interconversion along the continuous H-bonded network connecting the adsorbed water molecules.

15.
Nanomaterials (Basel) ; 11(3)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805652

RESUMO

In recent years, Metal-Organic Frameworks (MOFs) have attracted a growing interest for biomedical applications. The design of MOFs should take into consideration the subtle balance between stability and biodegradability. However, only few studies have focused on the MOFs' stability in physiological media and their degradation mechanism. Here, we investigate the degradation of mesoporous iron (III) carboxylate MOFs, which are among the most employed MOFs for drug delivery, by a set of complementary methods. In situ AFM allowed monitoring with nanoscale resolution the morphological, dimensional, and mechanical properties of a series of MOFs in phosphate buffer saline and in real time. Depending on the synthetic route, the external surface presented either well-defined crystalline planes or initial defects, which influenced the degradation mechanism of the particles. Moreover, MOF stability was investigated under different pH conditions, from acidic to neutral. Interestingly, despite pronounced erosion, especially at neutral pH, the dimensions of the crystals were unchanged. It was revealed that the external surfaces of MOF crystals rapidly respond to in situ changes of the composition of the media they are in contact with. These observations are of a crucial importance for the design of nanosized MOFs for drug delivery applications.

16.
Phys Chem Chem Phys ; 23(3): 2245-2251, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33443274

RESUMO

The 17O resonances of zirconium-oxo clusters that can be found in porous Zr carboxylate metal-organic frameworks (MOFs) have been investigated by magic-angle spinning (MAS) NMR spectroscopy enhanced by dynamic nuclear polarization (DNP). High-resolution 17O spectra at 0.037% natural abundance could be obtained in 48 hours, thanks to DNP enhancement of the 1H polarization by factors ε(1H) = Swith/Swithout = 28, followed by 1H → 17O cross-polarization, allowing a saving in experimental time by a factor of ca. 800. The distinct 17O sites from the oxo-clusters can be resolved at 18.8 T. Their assignment is supported by density functional theory (DFT) calculations of chemical shifts and quadrupolar parameters. Protonation of 17O sites seems to be leading to large characteristic shifts. Hence, natural abundance 17O NMR spectra of diamagnetic MOFs can thus be used to probe and characterize the local environment of different 17O sites on an atomic scale.

17.
Nanomaterials (Basel) ; 11(1)2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33435145

RESUMO

The Langmuir-Blodgett (LB) method is a well-known deposition technique for the fabrication of ordered monolayer and multilayer thin films of nanomaterials onto different substrates that plays a critical role in the development of functional devices for various applications. This paper describes detailed studies about the best coating configuration for nanoparticles of a porous metal-organic framework (MOF) onto both insulating or conductive threads and nylon fiber. We design and fabricate customized polymethylmethacrylate sheets (PMMA) holders to deposit MOF layers onto the threads or fiber using the LB technique. Two different orientations, namely, horizontal and vertical, are used to deposit MIL-96(Al) monolayer films onto five different types of threads and nylon fiber. These studies show that LB film formation strongly depends on deposition orientation and the type of threads or fiber. Among all the samples tested, cotton thread and nylon fiber with vertical deposition show more homogenous monolayer coverage. In the case of conductive threads, the MOF particles tend to aggregate between the conductive thread's fibers instead of forming a continuous monolayer coating. Our results show a significant contribution in terms of MOF monolayer deposition onto single fiber and threads that will contribute to the fabrication of single fiber or thread-based devices in the future.

18.
Angew Chem Int Ed Engl ; 60(8): 4282-4288, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33179846

RESUMO

Room-temperature syntheses of metal-organic frameworks (MOFs) are of interest to meet the demand of the sustainable chemistry and are a pre-requisite for the incorporation of functional compounds in water-stable MOFs. However, only few routes under ambient conditions have been reported to produce metal(IV)-based MOFs. Reported here is a new versatile one-step synthesis of a series of highly porous M6 -oxocluster-based MOFs (M=Zr, Hf, Ce) at room temperature, including 8- or 12-connected micro/mesoporous solids with different functionalized organic ligands. The compounds show varying degrees of defects, particularly for 12-connected phases, while maintaining the chemical stability of the parent MOFs. Proposed here are first insights into in situ kinetics observations for efficient MOF preparation. Remarkably, the synthesis has a high space-time yield and also provides the possibility to tune the particle size, therefore paving the way for their practical use.

19.
Angew Chem Int Ed Engl ; 59(26): 10353-10358, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32187798

RESUMO

An innovative strategy is proposed to synthesize single-crystal nanowires (NWs) of the Al3+ dicarboxylate MIL-69(Al) MOF by using graphene oxide nanoscrolls as structure-directing agents. MIL-69(Al) NWs with an average diameter of 70±20 nm and lengths up to 2 µm were found to preferentially grow along the [001] crystallographic direction. Advanced characterization methods (electron diffraction, TEM, STEM-HAADF, SEM, XPS) and molecular modeling revealed the mechanism of formation of MIL-69(Al) NWs involving size-confinement and templating effects. The formation of MIL-69(Al) seeds and the self-scroll of GO sheets followed by the anisotropic growth of MIL-69(Al) crystals are mediated by specific GO sheets/MOF interactions. This study delivers an unprecedented approach to control the design of 1D MOF nanostructures and superstructures.

20.
ACS Appl Mater Interfaces ; 12(3): 4155-4162, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31909968

RESUMO

The successful development of modern gas sensing technologies requires high sensitivity and selectivity coupled to cost effectiveness, which implies the necessity to miniaturize devices while reducing the amount of sensing material. The appealing alternative of integrating nanoparticles of a porous metal-organic framework (MOF) onto capacitive sensors based on interdigitated electrode (IDE) chips is presented. We report the deposition of MIL-96(Al) MOF thin films via the Langmuir-Blodgett (LB) method on the IDE chips, which allowed the study of their gas/vapor sensing properties. First, sorption studies of several organic vapors like methanol, toluene, chloroform, etc. were conducted on bulk MOF. The sorption data revealed that MIL-96(Al) presents high affinity toward water and methanol. Later on, ordered LB monolayer films of MIL-96(Al) particles of ∼200 nm were successfully deposited onto IDE chips with homogeneous coverage of the surface in comparison to conventional thin film fabrication techniques such as drop-casting. The sensing tests showed that MOF LB films were selective for water and methanol, and short response/recovery times were achieved. Finally, chemical vapor deposition (CVD) of a porous thin film of Parylene C (thickness ∼250-300 nm) was performed on top of the MOF LB films to fabricate a thin selective layer. The sensing results showed an increase in the water selectivity and sensitivity, while those of methanol showed a huge decrease. These results prove the feasibility of the LB technique for the fabrication of ordered MOF thin films onto IDE chips using very small MOF quantities.

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