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1.
J Am Chem Soc ; 146(1): 599-608, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38109168

RESUMO

The rapid development of antimicrobial resistance (AMR) among infectious pathogens has become a major threat and challenge in healthcare systems globally. A strategy distinct from minimizing the overuse of antimicrobials involves the development of novel antimicrobials with a mode of action that prevents the development of AMR microbial strains. Reactive oxygen species (ROS) are formed as a natural byproduct of the cellular aerobic metabolism. However, it becomes pathological when ROS is produced at excessive levels. Exploiting this phenomenon, research on redox-active bactericides has been demonstrated to be beneficial. Materials that release ROS via photodynamic, thermodynamic, and photocatalytic interventions have been developed as nanomedicines and are used in various applications. However, these materials require external stimuli for ROS release to be effective as biocides. In this paper, we report novel zinc-based metal organic framework (Zn@MOF) particles that promote the spontaneous release of active ROS species. The synthesized Zn@MOF spontaneously releases superoxide anions and hydrogen peroxide, exhibiting a potent antimicrobial efficacy against various microbes. Zn@MOF-incorporated plastic films and coatings show excellent, long-lasting antimicrobial potency even under continuous microbial challenge and an aging process. These disinfecting surfaces maintain their antimicrobial properties even after 500× surface wipes. Zn@MOF is also biocompatible and safe on the skin, illustrating its broad potential applications in medical technology and consumer care applications.


Assuntos
Anti-Infecciosos , Estruturas Metalorgânicas , Espécies Reativas de Oxigênio/metabolismo , Antibacterianos/farmacologia , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/metabolismo , Zinco , Oxirredução
2.
Anal Chem ; 96(6): 2727-2736, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38300748

RESUMO

Exosomes, a growing focus for liquid biopsies, contain diverse molecular cargos. In particular, exosome metabolites with valuable information have exhibited great potential for improving the efficiency of liquid biopsies for addressing complex medical conditions. In this work, we design the directional growth of Ti-metal-organic frameworks on polar-functionalized magnetic particles. This design facilitates the rapid synergistic capture of exosomes with the assistance of an external magnetic field and additionally synergistically enhances the ionization of their metabolites during mass spectrometry detection. Benefiting from this dual synergistic effect, we identified three high-performance exosome metabolites through the differential comparison of a large number of serum samples from individuals with Alzheimer's disease (AD) and normal cognition. Notably, the accuracy of AD identification ranges from 93.18 to 100% using a single exosome metabolite and reaches a flawless 100% with three metabolites. These findings emphasize the transformative potential of this work to enhance the precision and reliability of AD diagnosis, ushering in a new era of improved diagnostic accuracy.


Assuntos
Doença de Alzheimer , Exossomos , Estruturas Metalorgânicas , Humanos , Doença de Alzheimer/patologia , Estruturas Metalorgânicas/metabolismo , Exossomos/química , Reprodutibilidade dos Testes , Titânio/análise
3.
Small ; 20(1): e2304491, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37653587

RESUMO

A composite nanoagent capable of phototriggered tumor microenvironment (TME) regulation is developed based on copper (II) metal-organic frameworks (MOFs) with encapsulation of blebbistatin (Bb) and surface modification of fibroblast activation protein-αtargeted peptide (Tp). Tp enables active targeting of the nanoagents to cancer-associated fibroblast (CAF) while near-infrared light triggers Cu2+ -to-Cu+ photoreduction in MOFs, which brings about the collapse of MOFs and the release of Bb and Cu+ . Bb mediates photogeneration of hydroxyl radicals (•OH) and therefore inhibits extracellular matrix production by inducing CAF apoptosis, which facilitates the penetration of nanoagent to deep tumor tissue. The dual-channel generation of •OH based on Bb and the Cu+ species, via distinct mechanisms, synergistically reinforces oxidative stress in TME capable of inducing immunogenic cell death, which activates the antitumor immune response and therefore reverses the immunosuppressive TME. The synergistic antitumor phototherapy efficacy of such a type of nanoagent based on the abovementioned TME remodeling is unequivocally verified in a cell-derived tumor xenograft model.


Assuntos
Fibroblastos Associados a Câncer , Estruturas Metalorgânicas , Neoplasias , Humanos , Estruturas Metalorgânicas/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Microambiente Tumoral , Cobre/metabolismo , Neoplasias/metabolismo , Linhagem Celular Tumoral
4.
Chembiochem ; 25(17): e202400339, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38801661

RESUMO

Utilizing covalent organic frameworks (COFs) as porous supports to encapsulate enzyme represents an advanced strategy for constructing COFs biocatalysts, which has inspired numerous interests across various applications. As the structural advantages including ultrastable covalent-bonded linkage, tailorable pore structure, and metal-free biocompatibility, the resultant enzyme-COFs biocatalysts showcase functional enhancement in catalytic activity, chemical stability, long-term durability, and recyclability. This Concept describes the recent advances in the methodological strategies for engineering the COFs biocatalysts, with specific emphasis on the pore entrapment and in situ encapsulation strategies. The structural advantages of the COFs hybrid biocatalysts for organic synthesis, environment- and energy-associated applications are also canvassed. Additionally, the remaining challenges and the forward-looking directions in this field are also discussed. We believe that this Concept can offer useful methodological guidance for developing active and robust COFs biocatalysts.


Assuntos
Biocatálise , Enzimas Imobilizadas , Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Porosidade , Enzimas/metabolismo , Enzimas/química
5.
Chembiochem ; 25(12): e202400147, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629211

RESUMO

Chiral alcohols are not only important building blocks of various bioactive natural compounds and pharmaceuticals, but can serve as synthetic precursors for other valuable organic chemicals, thus the synthesis of these products is of great importance. Bio-catalysis represents one effective way to obtain these molecules, however, the weak stability and high cost of enzymes often hinder its broad application. In this work, we designed a biological nanoreactor by embedding alcohol dehydrogenase (ADH) and glucose dehydrogenase (GDH) in metal-organic-framework ZIF-8. The biocatalyst ADH&GDH@ZIF-8 could be applied to the asymmetric reduction of a series of ketones to give chiral alcohols in high yields (up to 99 %) and with excellent enantioselectivities (>99 %). In addition, the heterogeneous biocatalyst could be recycled and reused at least four times with slight activity decline. Moreover, E. coli containing ADH and GDH was immobilized by ZIF-8 to form biocatalyst E. coli@ZIF-8, which also exhibits good catalytic behaviours. Finally, the chiral alcohols are further converted to marketed drugs (R)-Fendiline, (S)-Rivastigmine and NPS R-568 respectively.


Assuntos
Álcool Desidrogenase , Biocatálise , Enzimas Imobilizadas , Escherichia coli , Glucose 1-Desidrogenase , Cetonas , Estruturas Metalorgânicas , Álcool Desidrogenase/metabolismo , Álcool Desidrogenase/química , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/metabolismo , Cetonas/química , Cetonas/metabolismo , Enzimas Imobilizadas/metabolismo , Enzimas Imobilizadas/química , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Glucose 1-Desidrogenase/metabolismo , Glucose 1-Desidrogenase/química , Oxirredução , Estereoisomerismo
6.
Small ; 19(22): e2300218, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36864579

RESUMO

Metal-organic framework (MOF) nanoparticles have recently emerged as a promising vehicle for drug delivery with high porosity and feasibility. However, employing a MOF-based drug delivery system remains a challenge due to the difficulty in controlling interfaces of particles in a biological environment. In this paper, protein corona-blocked Zr6 -based MOF (PCN-224) nanoparticles are presented for targeted cancer therapy with high efficiency. The unmodified PCN-224 surface is precoated with glutathione transferase (GST)-fused targetable affibody (GST-Afb) proteins via simple mixing conjugations instead of chemical modifications that can induce the impairment of proteins. GST-Afb proteins are shown to stably protect the surface of PCN-224 particles in a specific orientation with GST adsorbed onto the porous surface and the GST-linked Afb posed outward, minimizing the unwanted interfacial interactions of particles with external biological proteins. The Afb-directed cell-specific targeting ability of particles and consequent induction of cell death is demonstrated both in vitro and in vivo by using two kinds of Afb, which targets the surface membrane receptor, human epidermal growth factor receptor 2 (HER2) or epidermal growth factor receptor (EGFR). This study provides insight into the way of regulating the protein-adhesive surface of MOF nanoparticles and designing a more effective MOF-hosted targeted delivery system.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Humanos , Estruturas Metalorgânicas/metabolismo , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Proteínas de Membrana
7.
Chem Rev ; 121(3): 1077-1129, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33439632

RESUMO

Because of their efficiency, selectivity, and environmental sustainability, there are significant opportunities for enzymes in chemical synthesis and biotechnology. However, as the three-dimensional active structure of enzymes is predominantly maintained by weaker noncovalent interactions, thermal, pH, and chemical stressors can modify or eliminate activity. Metal-organic frameworks (MOFs), which are extended porous network materials assembled by a bottom-up building block approach from metal-based nodes and organic linkers, can be used to afford protection to enzymes. The self-assembled structures of MOFs can be used to encase an enzyme in a process called encapsulation when the MOF is synthesized in the presence of the biomolecule. Alternatively, enzymes can be infiltrated into mesoporous MOF structures or surface bound via covalent or noncovalent processes. Integration of MOF materials and enzymes in this way affords protection and allows the enzyme to maintain activity in challenge conditions (e.g., denaturing agents, elevated temperature, non-native pH, and organic solvents). In addition to forming simple enzyme/MOF biocomposites, other materials can be introduced to the composites to improve recovery or facilitate advanced applications in sensing and fuel cell technology. This review canvasses enzyme protection via encapsulation, pore infiltration, and surface adsorption and summarizes strategies to form multicomponent composites. Also, given that enzyme/MOF biocomposites straddle materials chemistry and enzymology, this review provides an assessment of the characterization methodologies used for MOF-immobilized enzymes and identifies some key parameters to facilitate development of the field.


Assuntos
Materiais Biocompatíveis/metabolismo , Enzimas/metabolismo , Estruturas Metalorgânicas/metabolismo , Materiais Biocompatíveis/química , Enzimas/química , Estruturas Metalorgânicas/química
8.
Angew Chem Int Ed Engl ; 62(47): e202308827, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37802975

RESUMO

Enzymatic catalysis with high efficiency allows them a great prospect in metabolite monitoring in living cells. However, complex tumor microenvironments, such as acidity, H2 O2 , and hypoxia, are bound to disturb catalytic reactions for misleading results. Here, we report a spatially compartmentalized artificial organelle to correct intratumoral glucose analysis, where the zeolitic imidazolate framework-8 immobilized glucose oxidase-horseradish peroxidase cascade core and catalase-directed shell act as signal transduction and guarding rooms respectively. The acid-digested core and stable shell provide appropriate spaces to boost biocatalytic efficiency with good tolerability. Notably, the endogenous H2 O2 is in situ decomposed to O2 by catalase, which not only overcomes the interference in signal output but also alleviates the hypoxic states to maximize glucose oxidation. The marked protective effect and biocompatibility render artificial organelles to correct the signal transduction for dynamic monitoring glucose in vitro and in vivo, achieving our goal of accurate intratumoral metabolite analysis.


Assuntos
Células Artificiais , Estruturas Metalorgânicas , Estruturas Metalorgânicas/metabolismo , Glucose/análise , Catalase/metabolismo , Oxirredução , Glucose Oxidase/metabolismo
9.
J Am Chem Soc ; 144(11): 4799-4809, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35192770

RESUMO

Chemodrug resistance is a major reason accounting for tumor recurrence. Given the mechanistic complexity of chemodrug resistance, molecular inhibitors and targeting drugs often fail to eliminate drug-resistant cancer cells, and sometimes even promote chemoresistance by activating alternative pathways. Here, by exploiting biochemical fragility of high-level but dynamically balanced cellular redox homeostasis in drug-resistant cancer cells, we design a nanosized copper/catechol-based metal-organic framework (CuHPT) that effectively disturbs this homeostasis tilting the balance toward oxidative stress. Within drug-resistant cells, CuHPT starts disassembly that is triggered by persistent consumption of cellular glutathione (GSH). CuHPT disassembly simultaneously releases two structural elements: catechol ligands and reductive copper ions (Cu+). Both of them cooperatively function to amplify the production of intracellular radical oxidative species (ROS) via auto-oxidation and Fenton-like reactions through exhausting GSH. By drastically heightening cellular oxidative stress, CuHPT exhibits selective and potent cytotoxicity to multiple drug-resistant cancer cells. Importantly, CuHPT effectively inhibits in vivo drug-resistant tumor growth and doubles the survival time of tumor-bearing mice. Thus, along with CuHPT's good biocompatibility, our biochemical, cell biological, preclinical animal model data provide compelling evidence supporting the notion that this copper-based MOF is a predesigned smart therapeutic against drug-resistant cancers through precisely deconstructing their redox homeostasis.


Assuntos
Estruturas Metalorgânicas , Neoplasias , Animais , Catecóis/farmacologia , Linhagem Celular Tumoral , Cobre/química , Resistencia a Medicamentos Antineoplásicos , Glutationa/metabolismo , Homeostase , Estruturas Metalorgânicas/metabolismo , Estruturas Metalorgânicas/farmacologia , Camundongos , Neoplasias/tratamento farmacológico , Oxirredução
10.
Anal Chem ; 94(18): 6827-6832, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35471823

RESUMO

The biomineralized metal-organic frameworks (MOFs) as protective layers help enhance the robustness of enzymes for biocatalysis. Despite great efforts, it is still challenging to develop a recyclable system with high payload and tolerance to harsh conditions. Here, we report a facile surface charge-independent strategy based on Zn-based coordination polymer (ZnCP) for nondestructive immobilization of enzyme. The ZnCP outcompetes most of the previously reported MOFs, in terms of high-payload enzyme packaging. Moreover, benefiting from the hydrophilicity of ZnCP, the entrapped enzymes (e.g., positive cytochrome C and negative glucose oxidase) maintained high catalytic activity, resembling their native counterparts. Notably, compared with ZIF-8, such enzyme-incorporated ZnCP (enzyme@ZnCP) is more tolerant to acidic pH, which imparts the enzyme with good recyclability, even in acid species-generated catalytic reactions, thus broadening its application in biocatalysis. The feasibility of enzyme@ZnCP for protein packaging, enzyme cascade catalysis, and biosensing was also validated. Altogether, enzyme@ZnCP demonstrates high enzyme payload, operational stability, and preservation of enzymatic activity, affording a versatile platform to accommodate bioactive enzyme for biocatalysis and biosensing.


Assuntos
Estruturas Metalorgânicas , Polímeros , Biocatálise , Enzimas Imobilizadas/metabolismo , Glucose Oxidase/metabolismo , Estruturas Metalorgânicas/metabolismo , Metais , Polímeros/metabolismo
11.
Anal Chem ; 94(2): 875-883, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34982534

RESUMO

Exosomes have emerged as a promising circulating tumor biomarker; however, it is a big challenge for convenient, multiparametric, and accurate profiling of tumorous exosomes due to their unique structure and heterogeneity. To address these problems, we develop a highly integrated electrochemical platform for molecular profiling of tumor exosomes. A metal-organic framework-functionalized sensing interface is fabricated through a simple self-growth process, which collects exosomes from biofluids without additional separation steps. Meanwhile, a sensing strategy is designed to analyze both exosomal protein and RNA markers on a single chip based on the unique sensor architecture, allowing detection of low-abundance targets (∼250 vesicles in a 10 µL sample) using an integrated microfluidic electrochemical device. Furthermore, a multiple-input, protein enzyme-based logic gate is introduced into the system to accurately identify breast cancer patients with 100% sensitivity and specificity, thus revealing the advantageous role of logical profiling of exosomes in early diagnostics of tumor.


Assuntos
Neoplasias da Mama , Exossomos , Estruturas Metalorgânicas , Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Exossomos/química , Feminino , Humanos , Dispositivos Lab-On-A-Chip , Estruturas Metalorgânicas/metabolismo
12.
Chem Soc Rev ; 50(7): 4541-4563, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33625421

RESUMO

Stimuli-responsive metal-organic framework nanoparticles, NMOFs, provide a versatile platform for the controlled release of drugs and biomedical applications. The porous structure of NMOFs, their biocompatibility, low toxicity, and efficient permeability turn the NMOFs into ideal carriers for therapeutic applications. Two general methods to gate the drug-loaded NMOFs and to release the loads were developed: by one method, the loaded NMOFs are coated or surface-modified with stimuli-responsive gates being unlocked in the presence of appropriate chemical (e.g., ions or reducing agents), physical (e.g., light or heat), or biomarker (e.g., miRNA or ATP) triggers. By a second approach, the drug-loaded NMOFs include encoded structural information or co-added agents to induce the structural distortion or stimulate the degradation of the NMOFs. Different chemical triggers such as pH changes, ions, ATP, or redox agents, and physical stimuli such as light or heat are applied to degrade the NMOFs, resulting in the release of the loads. In addition, enzymes, DNAzymes, and disease-specific biomarkers are used to unlock the gated NMOFs. The triggered release of drugs for cancer therapy, anti-blood clotting, and the design of autonomous insulin-delivery systems ("artificial pancreas") are discussed. Specifically, multi-drug carrier systems and functional NMOFs exhibiting dual and cooperative therapeutic functions are introduced. The future perspectives and applications of stimuli-responsive particles are addressed.


Assuntos
Pesquisa Biomédica , Sistemas de Liberação de Medicamentos , Estruturas Metalorgânicas/química , Nanopartículas/química , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/metabolismo , Nanopartículas/metabolismo
13.
Angew Chem Int Ed Engl ; 61(24): e202203115, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35395111

RESUMO

Metal-organic-framework nanoparticles (MOF NPs) have been increasingly used to encapsulate therapeutic enzymes for delivery. To better interface these MOF NPs with biological systems, researchers have coated them with natural cell membranes, enabling biomimicking properties suitable for innovative biomedical applications. Herein, we report that the enzymatic activity of cell-membrane-coated MOF NPs can be significantly enhanced by reducing membrane cholesterol content. We demonstrate such cholesterol-enzymatic activity correlation using zeolitic imidazolate framework-8 MOF NPs to encapsulate catalase, horseradish peroxidase, and organophosphate hydrolase, respectively. MOF NPs coated with membranes of human red blood cells or macrophages show similar outcomes, illustrating the broad applicability of this finding. The mechanistic investigation further reveals that reducing cholesterol levels effectively enhances membrane permeability likely responsible for the increased enzymatic activity. These results also imply a facile approach to tailoring the enzymatic activity of cell-membrane-coated MOF NPs by simply tuning the membrane cholesterol level.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Zeolitas , Membrana Celular/metabolismo , Humanos , Estruturas Metalorgânicas/metabolismo
14.
Angew Chem Int Ed Engl ; 61(18): e202117144, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35133704

RESUMO

Fully exploiting the potential of enzymes in cell-free biocatalysis requires stabilization of the catalytically active proteins and their integration into efficient reactor systems. Although in recent years initial steps towards the immobilization of such biomolecules in metal-organic frameworks (MOFs) have been taken, these demonstrations have been limited to batch experiments and to aqueous conditions. Here we demonstrate a MOF-based continuous flow enzyme reactor system, with high productivity and stability, which is also suitable for organic solvents. Under aqueous conditions, the stability of the enzyme was increased 30-fold, and the space-time yield exceeded that obtained with other enzyme immobilization strategies by an order of magnitude. Importantly, the infiltration of the proteins into the MOF did not require additional functionalization, thus allowing for time- and cost-efficient fabrication of the biocatalysts using label-free enzymes.


Assuntos
Enzimas Imobilizadas , Estruturas Metalorgânicas , Biocatálise , Catálise , Enzimas/metabolismo , Enzimas Imobilizadas/metabolismo , Estruturas Metalorgânicas/metabolismo , Proteínas/metabolismo , Solventes
15.
J Am Chem Soc ; 143(2): 1107-1118, 2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33411525

RESUMO

Artificial enzymatic systems are extensively studied to mimic the structures and functions of their natural counterparts. However, there remains a significant gap between structural modeling and catalytic activity in these artificial systems. Herein we report a novel strategy for the construction of an artificial binuclear copper monooxygenase starting from a Ti metal-organic framework (MOF). The deprotonation of the hydroxide groups on the secondary building units (SBUs) of MIL-125(Ti) (MIL = Matériaux de l'Institut Lavoisier) allows for the metalation of the SBUs with closely spaced CuI pairs, which are oxidized by molecular O2 to afford the CuII2(µ2-OH)2 cofactor in the MOF-based artificial binuclear monooxygenase Ti8-Cu2. An artificial mononuclear Cu monooxygenase Ti8-Cu1 was also prepared for comparison. The MOF-based monooxygenases were characterized by a combination of thermogravimetric analysis, inductively coupled plasma-mass spectrometry, X-ray absorption spectroscopy, Fourier-transform infrared spectroscopy, and UV-vis spectroscopy. In the presence of coreductants, Ti8-Cu2 exhibited outstanding catalytic activity toward a wide range of monooxygenation processes, including epoxidation, hydroxylation, Baeyer-Villiger oxidation, and sulfoxidation, with turnover numbers of up to 3450. Ti8-Cu2 showed a turnover frequency at least 17 times higher than that of Ti8-Cu1. Density functional theory calculations revealed O2 activation as the rate-limiting step in the monooxygenation processes. Computational studies further showed that the Cu2 sites in Ti8-Cu2 cooperatively stabilized the Cu-O2 adduct for O-O bond cleavage with 6.6 kcal/mol smaller free energy increase than that of the mononuclear Cu sites in Ti8-Cu1, accounting for the significantly higher catalytic activity of Ti8-Cu2 over Ti8-Cu1.


Assuntos
Cobre/metabolismo , Estruturas Metalorgânicas/metabolismo , Oxigenases de Função Mista/metabolismo , Cobre/química , Teoria da Densidade Funcional , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Oxigenases de Função Mista/química , Modelos Moleculares
16.
J Am Chem Soc ; 143(49): 20939-20951, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34851640

RESUMO

Natural transport channels (or carriers), such as aquaporins, are a distinct type of biomacromolecule capable of highly effective transmembrane transport of water or ions. Such behavior is routine for biology but has proved difficult to achieve in synthetic systems. Perhaps most significantly, the enantioselective transmembrane transport of biomolecules is an especially challenging problem both for chemists and for natural systems. Herein, a group of homochiral zirconium metal-organic cages with four triangular opening windows have been proposed as artificial biomolecular channels for enantioselective transmembrane transport of natural amino acids. These structurally well-defined coordination cages are assembled from six synthetically accessible BINOL-derived chiral ligands as spacers and four n-Bu3-Cp3Zr3 clusters as vertices, forming tetrahedral-shaped architectures that feature an intrinsically chiral cavity decorated with an array of specifically positioned binding sites mediated from phenol to phenyl ether to crown ether groups. Fascinatingly, the transformation of single-molecule chirality to global supramolecular chirality within the space-restricted chiral microenvironments accompanies unprecedented chiral amplification, leading to the enantiospecific recognition of amino acids. By virtue of the highly structural stability and excellent biocompatibility, the orientation-independent cages can be molecularly embedded into lipid membranes, biomimetically serving as single-molecular chiral channels for polar-residue amino acids, with the properties that cage-1 featuring hydroxyl groups preferentially transports the l-asparagine, whereas cage-2 attaching crown ether groups spontaneously favor transporting d-arginine. We therefore develop a new type of self-assembled system that can potentially mimic the functions of transmembrane proteins in nature, which is a realistic candidate for further biomedical applications.


Assuntos
Aminoácidos/metabolismo , Transporte Biológico/efeitos dos fármacos , Portadores de Fármacos/química , Estruturas Metalorgânicas/química , Aminoácidos/química , Teoria da Densidade Funcional , Portadores de Fármacos/síntese química , Portadores de Fármacos/metabolismo , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/metabolismo , Modelos Químicos , Fosfatidilcolinas/química , Estereoisomerismo , Lipossomas Unilamelares/química , Lipossomas Unilamelares/metabolismo , Zircônio/química
17.
Small ; 17(32): e2100300, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33949785

RESUMO

Biocatalysts immobilization with nanomaterials has promoted the development of biocatalysis significantly and made it an indispensable part of catalysis industries nowadays. Metal-organic frameworks (MOFs), constructed from organic linkers and metal ions or clusters, have raised significant interests for biocatalysts immobilization in recent years. The diversity of building units, molecular-scale tunability, and modular synthetic routes of MOFs greatly expand its ability as the host to integrate with biocatalysts. In this review, the general synthetic strategies of MOFs with biocatalysts are first summarized. Then, the recent progress of MOFs as a versatile host for a series of biocatalysts, including natural enzymes, nanozymes, and organism-based biocatalysts, followed by the introduction of MOFs themselves as biocatalysts, is discussed. Furthermore, the stimuli-responsive properties of MOFs themselves or the additional functionalization of protein, polymer, and peptide within/on MOF that enable the biocatalysts with the controllable and tunable behavior are also summarized, which could unlock new potentials in biocatalysis. Finally, a perspective of the upcoming challenges, potential impacts, and future directions of biocatalytic MOFs is provided.


Assuntos
Estruturas Metalorgânicas , Nanoestruturas , Biocatálise , Catálise , Estruturas Metalorgânicas/metabolismo
18.
Nanotechnology ; 32(29)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33853047

RESUMO

This paper applied mesoporous metal-organic frameworks (MOFs) of UiO-66 particles for pH-responsive doxorubicin (DOX) delivery and cancer treatment. Mesoporous structured UiO-66 MOFs were synthesized, and carboxymethylcellulose (CMC) was loaded for sensitive pH response and also as a linker to encapsulate the chemotherapeutic drug of DOX. The composite of UiO-66/CMC@DOX was synthesized, and the loading capacity was as high as 45µg DOX per mg of the carrier. The structure and crystalization of the UiO-66 MOFs were determined by the Transmitting Electron Microscope (TEM) and x-ray diffraction methods, while the loading of CMC and DOX was inspected by Fourier Transform InfraRed (FT-IR) and UV-vis spectroscopy. The DOX release from UiO-66/CMC@DOX was tested under different pH at 37 °C. The DOX accumulative release could reach 78% under the pH of 5. A lower pH was more favorable for DOX release due to the CMC shrinking and higher DOX solubility in an acidic environment. The cytotoxicity study indicated that, under the DOX concentration of 4µg ml-1, the A549 cell (Lung Carcinoma Cell Line) viability of UiO-66/CMC was 28%, which was lower than that from free DOX solution (47%). UiO-66 MOFs were demonstrated to be an efficient drug delivery carrier for chemotherapeutic drug and release.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Carboximetilcelulose Sódica/química , Doxorrubicina/farmacologia , Portadores de Fármacos , Estruturas Metalorgânicas/síntese química , Compostos Organometálicos/química , Ácidos Ftálicos/química , Células A549 , Antibióticos Antineoplásicos/química , Apoptose/efeitos dos fármacos , Doxorrubicina/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Cinética , Estruturas Metalorgânicas/metabolismo , Porosidade
19.
Mikrochim Acta ; 188(7): 225, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34104996

RESUMO

A novel magnetic borate-functionalized metal-organic framework nanocomposite was designed and fabricated for selective enrichment of catecholamines from human urine. Firstly, the polytannic acid (PTA) layer with natural low-cost and ecofriendly polyphenol tannic acid as the organic ligand and Fe3+ as the cross-linker was coated onto the surface of Fe3O4. Then, the borate-functionalized metal-organic framework (MIL-100(Fe)-B) with 5-boronobenzene-1,3-dicarboxylic acid as a ligand fragment was modified onto the PTA-coated Fe3O4 through a metal-ligand-fragment coassembly strategy. The obtained smart porous adsorbent Fe3O4@PTA@MIL-100(Fe)-B was confirmed by means of several characterization methods and then applied as an effective magnetic solid phase extraction (MSPE) sorbent for specific extraction of trace catecholamines in human urine. The Plackett-Burman design was used for screening the variables significantly affecting the extraction efficiency. Then, the significant factors were further investigated by the Box-Behnken design to determine the optimal extraction conditions. Under the optimal conditions, a method for selective MSPE combined with high-performance liquid chromatography with a fluorescence detector for the quantitation of catecholamines in human urine was developed and validated. With the proposed method, the linearity range was from 0.500 to 500 ng mL-1 for norepinephrine and epinephrine and from 1.00 to 500 ng mL-1 for dopamine. The detection limits were 0.050, 0.11, and 0.20 ng mL-1 for norepinephrine, epinephrine, and dopamine, respectively. The recoveries from spiking experiments varied from 91.5 to 108% with relative standard deviations (RSDs) of 0.80-4.8%. The established method is rapid, sensitive, accurate, inexpensive, and ecofriendly and was successfully applied to the determination of the target catecholamines in human urine samples.


Assuntos
Ácidos Borônicos/metabolismo , Catecolaminas/urina , Estruturas Metalorgânicas/metabolismo , Taninos/metabolismo , Humanos , Fenômenos Magnéticos
20.
Molecules ; 26(5)2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33800017

RESUMO

Metal-organic frameworks (MOFs) have become one of the versatile solid materials used for a wide range of applications, such as gas storage, gas separation, proton conductivity, sensors and catalysis. Among these fields, one of the more well-studied areas is the use of MOFs as heterogeneous catalysts for a broad range of organic reactions. In the present review, the employment of MOFs as solid catalysts for the Henry reaction is discussed, and the available literature data from the last decade are grouped. The review is organized with a brief introduction of the importance of Henry reactions and structural properties of MOFs that are suitable for catalysis. The second part of the review discusses the use of MOFs as solid catalysts for the Henry reaction involving metal nodes as active sites, while the third section provides data utilizing basic sites (primary amine, secondary amine, amides and urea-donating sites). While commenting on the catalytic results in these two sections, the advantage of MOFs over other solid catalysts is compared in terms of activity by providing turnover number (TON) values and the structural stability of MOFs during the course of the reaction. The final section provides our views on further directions in this field.


Assuntos
Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/metabolismo , Amidas/química , Aminas/química , Catálise , Domínio Catalítico , Cobre/química , Ureia/química
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