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1.
Angew Chem Int Ed Engl ; 63(12): e202314501, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38302821

RESUMO

Due to the presence of natural neoantigens, autologous tumor cells hold great promise as personalized therapeutic vaccines. Yet autologous tumor cell vaccines require multi-step production that frequently leads to the loss of immunoreactive antigens, causing insufficient immune activation and significantly hampering their clinical applications. Herein, we introduce a novel whole-cell cancer vaccine by cloaking cancer cells with lipopolysaccharide-decorated manganese(II)-phenolic networks (MnTA nanocloaks) to evoke tumor-specific immune response for highly efficacious synergistic cancer immunotherapy. The natural polyphenols coordinate with Mn2+ and immediately adhere to the surface of individual cancer cells, thereby forming a nanocloak and encapsulating tumor neoantigens. Subsequent decoration with lipopolysaccharide induces internalization by dendritic cells, where Mn2+ ions are released in the cytosol, further facilitating the activation of the stimulator of the interferon genes (STING) pathway. Highly effective tumor suppression was observed by combining the nanocloaked cancer cell treatment with anti-programmed cell death ligand 1 (anti-PD-L1) antibodies-mediated immune checkpoint blockade therapy. Our work demonstrates a universal yet simple strategy to engineer a cell-based nanobiohybrid system for enhanced cancer immunotherapy.


Assuntos
Neoplasias , Vacinas , Humanos , Imunoterapia , Lipopolissacarídeos , Neoplasias/terapia , Microambiente Tumoral , Vacinas Anticâncer
2.
J Am Chem Soc ; 145(44): 24108-24115, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37788442

RESUMO

Protocells have garnered considerable attention from cell biologists, materials scientists, and synthetic biologists. Phase-separating coacervate microdroplets have emerged as a promising cytomimetic model because they can internalize and concentrate components from dilute surrounding environments. However, the membrane-free nature of such coacervates leads to coalescence into a bulk phase, a phenomenon that is not representative of the cells they are designed to mimic. Herein, we develop a membranized peptide coacervate (PC) with oppositely charged oligopeptides as the molecularly crowded cytosol and a metal-phenolic network (MPN) coating as the membrane. The hybrid protocell efficiently internalizes various bioactive macromolecules (e.g., bovine serum albumin and immunoglobulin G) (>90%) while also resisting radicals due to the semipermeable cytoprotective membrane. Notably, the resultant PC@MPNs are capable of anabolic cascade reactions and remain in discrete protocellular populations without coalescence. Finally, we demonstrate that the MPN protocell membrane can be postfunctionalized with various functional molecules (e.g., folic acid and fluorescence dye) to more closely resemble actual cells with complex membranes, such as recognition molecules, which allows for drug delivery. This membrane-bound cytosolic protocell structure paves the way for innovative synthetic cells with structural and functional complexity.


Assuntos
Células Artificiais , Células Artificiais/química , Peptídeos , Soroalbumina Bovina/química , Substâncias Macromoleculares
3.
Angew Chem Int Ed Engl ; 62(14): e202218021, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36732289

RESUMO

Nanostructured materials with tunable structures and functionality are of interest in diverse areas. Herein, metal ions are coordinated with quinones through metal-acetylacetone coordination bonds to generate a class of structurally tunable, universally adhesive, hydrophilic, and pH-degradable materials. A library of metal-quinone networks (MQNs) is produced from five model quinone ligands paired with nine metal ions, leading to the assembly of particles, tubes, capsules, and films. Importantly, MQNs show bidirectional pH-responsive disassembly in acidic and alkaline solutions, where the quinone ligands mediate the disassembly kinetics, enabling temporal and spatial control over the release of multiple components using multilayered MQNs. Leveraging this tunable release and the inherent medicinal properties of quinones, MQN prodrugs with a high drug loading (>89 wt %) are engineered using doxorubicin for anti-cancer therapy and shikonin for the inhibition of the main protease in the SARS-CoV-2 virus.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Metais/química , Quinonas/farmacologia
4.
Adv Sci (Weinh) ; 10(9): e2206546, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36698301

RESUMO

Antibody-nanoparticle conjugates are promising candidates for precision medicine. However, developing a controllable method for conjugating antibodies to nanoparticles without compromising the antibody activity represents a critical challenge. Here, a facile and generalizable film-coating method is presented using zeolitic imidazole framework-8 (ZIF-8) to immobilize antibodies on various nanoparticles in a favorable orientation for enhanced cell targeting. Different model and therapeutic antibodies (e.g., Herceptin) are assembled on nanoparticles via a biomineralized film-coating method and exhibited high antibody loading and targeting efficiencies. Importantly, the antibodies selectively bind to ZIF-8 via their Fc regions, which favorably exposes the functional Fab regions to the biological target, thus improving the cell targeting ability of antibody-coated nanoparticles. In combination, molecular dynamics simulations and experimental studies on antibody immobilization, orientation efficiency, and biofunctionality collectively demonstrate that this versatile site-specific antibody conjugation method provides effective control over antibody orientation and leads to improved cell targeting for a variety of nanoparticles.


Assuntos
Nanopartículas Metálicas , Especificidade de Anticorpos , Sistemas de Liberação de Medicamentos , Estruturas Metalorgânicas/química , Nanopartículas Metálicas/química
5.
Nanoscale ; 14(39): 14466-14470, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36149411

RESUMO

Tannic acid (TA) is a structurally undefined natural dendritic polyphenol. Here, we introduce a series of TA-inspired polymers with different arm lengths, Mn, and phenolic groups that can be used to engineer metal-phenolic network (MPN) capsules with different properties including controlled permeability, high biocompatibility, and fluorescence.

6.
J Am Chem Soc ; 144(27): 12510-12519, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35775928

RESUMO

Supramolecular assembly affords the development of a wide range of polypeptide-based biomaterials for drug delivery and nanomedicine. However, there remains a need to develop a platform for the rapid synthesis and study of diverse polypeptide-based materials without the need for employing complex chemistries. Herein, we develop a versatile strategy for creating polypeptide-based materials using polyphenols that display multiple synergistic cross-linking interactions with different polypeptide side groups. We evaluated the diverse interactions operating within these polypeptide-polyphenol networks via binding affinity, thermodynamics, and molecular docking studies and found that positively charged polypeptides (Ka of ∼2 × 104 M-1) and polyproline (Ka of ∼2 × 106 M-1) exhibited stronger interactions with polyphenols than other amino acids (Ka of ∼2 × 103 M-1). Free-standing particles (capsules) were obtained from different homopolypeptides using a template-mediated strategy. The properties of the capsules varied with the homopolypeptide used, for example, positively charged polypeptides produced thicker shell walls (120 nm) with reduced permeability and involved multiple interactions (i.e., electrostatic and hydrogen), whereas uncharged polypeptides generated thinner (10 nm) and more permeable shell walls due to the dominant hydrophobic interactions. Polyarginine imparted cell penetration and endosomal escape properties to the polyarginine-tannic acid capsules, enabling enhanced delivery of the drug doxorubicin (2.5 times higher intracellular fluorescence after 24 h) and a corresponding higher cell death in vitro when compared with polyproline-tannic acid capsules. The ability to readily complex polyphenols with different types of polypeptides highlights that a wide range of functional materials can be generated for various applications.


Assuntos
Peptídeos , Polifenóis , Cápsulas/química , Sistemas de Liberação de Medicamentos , Simulação de Acoplamento Molecular , Peptídeos/química , Taninos/química
7.
Chem Soc Rev ; 51(11): 4287-4336, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35471996

RESUMO

Advanced treatments based on immune system manipulation, gene transcription and regulation, specific organ and cell targeting, and/or photon energy conversion have emerged as promising therapeutic strategies against a range of challenging diseases. Naturally derived macromolecules (e.g., proteins, lipids, polysaccharides, and polyphenols) have increasingly found use as fundamental building blocks for nanostructured particles as their advantageous properties, including biocompatibility, biodegradability, inherent bioactivity, and diverse chemical properties make them suitable for advanced therapeutic applications. This review provides a timely and comprehensive summary of the use of a broad range of natural building blocks in the rapidly developing field of advanced therapeutics with insights specific to nanostructured particles. We focus on an up-to-date overview of the assembly of nanostructured particles using natural building blocks and summarize their key scientific and preclinical milestones for advanced therapies, including adoptive cell therapy, immunotherapy, gene therapy, active targeted drug delivery, photoacoustic therapy and imaging, photothermal therapy, and combinational therapy. A cross-comparison of the advantages and disadvantages of different natural building blocks are highlighted to elucidate the key design principles for such bio-derived nanoparticles toward improving their performance and adoption. Current challenges and future research directions are also discussed, which will accelerate our understanding of designing, engineering, and applying nanostructured particles for advanced therapies.


Assuntos
Nanopartículas , Nanoestruturas , Sistemas de Liberação de Medicamentos , Terapia Genética , Substâncias Macromoleculares , Nanopartículas/química , Nanoestruturas/uso terapêutico
8.
Sci Rep ; 12(1): 2071, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136104

RESUMO

The development of antimicrobial fabrics and textiles that can sustainably inhibit a broad spectrum of microbes is crucial for protecting against pathogens in various environments. However, engineering antimicrobial textiles is challenging due to issues with discoloration and inhibited breathability, the use of harmful or harsh reagents and synthesis conditions, and complex and/or time-consuming processing. Herein, we develop a facile and rapid approach to deposit antimicrobial coatings using universally adherent plant polyphenols and antimicrobial silver ions. Importantly, the coatings are colorless, thin (< 10 nm), rapidly assembled (< 20 min), and can be deposited via immersion or spraying. We demonstrate that these metal-phenolic coatings on textiles can inhibit lipid-enveloped viruses over one thousand times more efficiently than coatings composed of other metal ions, while maintaining their efficacy even after 5 washes. Moreover, the coatings also inhibit Gram positive and negative bacteria, and fungi, and can prevent odors on clothes for at least 10 washes. Collectively, the ease of synthesis, use of simple and safe precursors, and amenability to at-home and industrial application suggests that the coatings will find practical application in various settings.

9.
Adv Mater ; 34(10): e2108624, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34933398

RESUMO

The integration of bioactive materials (e.g., proteins and genes) into nanoparticles holds promise in fields ranging from catalysis to biomedicine. However, it is challenging to develop a simple and broadly applicable nanoparticle platform that can readily incorporate distinct biomacromolecules without affecting their intrinsic activity. Herein, a metal-phenolic assembly approach is presented whereby diverse functional nanoparticles can be readily assembled in water by combining various synthetic and natural building blocks, including poly(ethylene glycol), phenolic ligands, metal ions, and bioactive macromolecules. The assembly process is primarily mediated by metal-phenolic complexes through coordination and hydrophobic interactions, which yields uniform and spherical nanoparticles (mostly <200 nm), while preserving the function of the incorporated biomacromolecules (siRNA and five different proteins used). The functionality of the assembled nanoparticles is demonstrated through cancer cell apoptosis, RNA degradation, catalysis, and gene downregulation studies. Furthermore, the resulting nanoparticles can be used as building blocks for the secondary engineering of superstructures via templating and cross-linking with metal ions. The bioactivity and versatility of the platform can potentially be used for the streamlined and rational design of future bioactive materials.


Assuntos
Nanopartículas , Catálise , Interações Hidrofóbicas e Hidrofílicas , Metais/química , Nanopartículas/química , Fenóis/química
10.
Angew Chem Int Ed Engl ; 60(47): 24968-24975, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34528750

RESUMO

The development of fluorescence labeling techniques has attracted widespread interest in various fields, including biomedical science as it can facilitate high-resolution imaging and the spatiotemporal understanding of various biological processes. We report a supramolecular fluorescence labeling strategy using luminescent metal-phenolic networks (MPNs) constructed from metal ions, phenolic ligands, and common and commercially available dyes. The rapid labeling process (<5 min) produces ultrathin coatings (≈10 nm) on diverse particles (e.g., organic, inorganic, and biological entities) with customized luminescence (e.g., red, blue, multichromatic, and white light) simply through the selection of fluorophores. The fluorescent coatings are stable at pH values from 1 to 8 and in complex biological media owing to the dominant π interactions between the dyes and MPNs. These coatings exhibit negligible cytotoxicity and their strong fluorescence is retained even when internalized into intracellular compartments. This strategy is expected to provide a versatile approach for fluorescence labeling with potential in diverse fields across the physical and life sciences.


Assuntos
Cor , Corantes Fluorescentes/química , Estruturas Metalorgânicas/química , Metais Pesados/química , Fenóis/química , Tamanho da Partícula
11.
Sci Adv ; 7(37): eabh3482, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34516887

RESUMO

Soft structures in nature, such as supercoiled DNA and proteins, can organize into complex hierarchical architectures through multiple noncovalent molecular interactions. Identifying new classes of natural building blocks capable of facilitating long-range hierarchical structuring has remained an elusive goal. We report the bottom-up synthesis of a hierarchical metal-phenolic mesocrystal where self-assembly proceeds on different length scales in a spatiotemporally controlled manner. Phenolic-based coordination complexes organize into supramolecular threads that assemble into tertiary nanoscale filaments, lastly packing into quaternary mesocrystals. The hierarchically ordered structures are preserved after thermal conversion into a metal-carbon hybrid framework and can impart outstanding performance to sodium ion batteries, which affords a capability of 72.5 milliampere hours per gram at an ultrahigh rate of 200 amperes per gram and a 90% capacity retention over 15,000 cycles at a current density of 5.0 amperes per gram. This hierarchical structuring of natural polyphenols is expected to find widespread applications.

12.
Angew Chem Int Ed Engl ; 60(37): 20225-20230, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34258845

RESUMO

Interfacial modular assembly has emerged as an adaptable strategy for engineering the surface properties of substrates in biomedicine, photonics, and catalysis. Herein, we report a versatile and robust coating (pBDT-TA), self-assembled from tannic acid (TA) and a self-polymerizing aromatic dithiol (i.e., benzene-1,4-dithiol, BDT), that can be engineered on diverse substrates with a precisely tuned thickness (5-40 nm) by varying the concentration of BDT used. The pBDT-TA coating is stabilized by covalent (disulfide) bonds and supramolecular (π-π) interactions, endowing the coating with high stability in various harsh aqueous environments across ionic strength, pH, temperature (e.g., 100 mM NaCl, HCl (pH 1) or NaOH (pH 13), and water at 100 °C), as well as surfactant solution (e.g., 100 mM Triton X-100) and biological buffer (e.g., Dulbecco's phosphate-buffered saline), as validated by experiments and simulations. Moreover, the reported pBDT-TA coating enables secondary reactions on the coating for engineering hybrid adlayers (e.g., ZIF-8 shells) via phenolic-mediated adhesion, and the facile integration of aromatic fluorescent dyes (e.g., rhodamine B) via π interactions without requiring elaborate synthetic processes.


Assuntos
Corantes Fluorescentes/química , Imidazóis/química , Estruturas Metalorgânicas/química , Rodaminas/química , Compostos de Sulfidrila/química , Taninos/química , Concentração de Íons de Hidrogênio , Estrutura Molecular , Concentração Osmolar , Temperatura
13.
Hum Reprod ; 36(7): 1776-1783, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-33975346

RESUMO

STUDY QUESTION: Can vascular endothelial growth factor (VEGF)-loaded silica supraparticles (V-SPs) be used as a novel mode of delivering VEGF to the developing preimplantation embryo in vitro? SUMMARY ANSWER: Supplementation of embryo culture media with V-SPs promoted embryonic development in a manner equivalent to media supplemented with free VEGF. WHAT IS KNOWN ALREADY: VEGF is a maternally derived growth factor that promotes preimplantation embryonic development in vitro. However, its use in clinical media has limitations due to its low stability in solution. STUDY DESIGN, SIZE, DURATION: This study was a laboratory-based analysis utilising a mouse model. V-SPs were prepared in vitro and supplemented to embryonic culture media. The bioactivity of V-SPs was determined by analysis of blastocyst developmental outcomes (blastocyst development rate and total cell number). PARTICIPANTS/MATERIALS, SETTING, METHODS: SPs were loaded with fluorescently labelled VEGF and release kinetics were characterised. Bioactivity of unlabelled VEGF released from V-SPs was determined by analysis of embryo developmental outcomes (blastocyst developmental rate and total cell number) following individual mouse embryo culture in 20 µl of G1/G2 media at 5% oxygen, supplemented with 10 ng/ml recombinant mouse VEGF in solution or with V-SPs. The bioactivity of freeze-dried V-SPs was also assessed to determine the efficacy of cryostorage. MAIN RESULTS AND THE ROLE OF CHANCE: VEGF release kinetics were characterised by an initial burst of VEGF from loaded spheres followed by a consistent lower level of VEGF release over 48 h. VEGF released from V-SPs resulted in significant increases in total blastocyst cell number relative to the control (P < 0.001), replicating the effects of medium freely supplemented with fresh VEGF (P < 0.001). Similarly, freeze dried V-SPs exerted comparable effects on embryonic development (P < 0.05). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: In this proof of principle study, the effects of V-SPs on embryonic development were only analysed in a mouse model. WIDER IMPLICATIONS OF THE FINDINGS: These findings suggest that SPs represent a novel method by which a targeted dose of therapeutic agents (e.g. bioactive VEGF) can be delivered to the developing in vitro embryo to promote embryonic development, an approach that negates the breakdown of VEGF associated with storage in solution. As such, V-SPs may be an alternative and effective method of delivering bioactive VEGF to the developing in vitro embryo; however, the potential use of V-SPs in clinical IVF requires further investigation. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by the University of Melbourne. The authors have no conflict of interest to declare.


Assuntos
Técnicas de Cultura Embrionária , Fator A de Crescimento do Endotélio Vascular , Animais , Blastocisto , Meios de Cultura , Desenvolvimento Embrionário , Feminino , Camundongos , Projetos Piloto , Gravidez
14.
Biomacromolecules ; 22(2): 612-619, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33337863

RESUMO

Poly(ethylene glycol) (PEG) is well known to endow nanoparticles (NPs) with low-fouling and stealth-like properties that can reduce immune system clearance in vivo, making PEG-based NPs (particularly sub-100 nm) of interest for diverse biomedical applications. However, the preparation of sub-100 nm PEG NPs with controllable size and morphology is challenging. Herein, we report a strategy based on the noncovalent coordination between PEG-polyphenolic ligands (PEG-gallol) and transition metal ions using a water-in-oil microemulsion phase to synthesize sub-100 nm PEG NPs with tunable size and morphology. The metal-phenolic coordination drives the self-assembly of the PEG-gallol/metal NPs: complexation between MnII and PEG-gallol within the microemulsions yields a series of metal-stabilized PEG NPs, including 30-50 nm solid and hollow NPs, depending on the MnII/gallol feed ratio. Variations in size and morphology are attributed to the changes in hydrophobicity of the PEG-gallol/MnII complexes at varying MnII/gallol ratios based on contact angle measurements. Small-angle X-ray scattering analysis, which is used to monitor the particle size and intermolecular interactions during NP evolution, reveals that ionic interactions are the dominant driving force in the formation of the PEG-gallol/MnII NPs. pH and cytotoxicity studies, and the low-fouling properties of the PEG-gallol/MnII NPs confirm their high biocompatibility and functionality, suggesting that PEG polyphenol-metal NPs are promising systems for biomedical applications.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Polietilenoglicóis
15.
Nat Commun ; 11(1): 4804, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968077

RESUMO

We report a facile strategy for engineering diverse particles based on the supramolecular assembly of natural polyphenols and a self-polymerizable aromatic dithiol. In aqueous conditions, uniform and size-tunable supramolecular particles are assembled through π-π interactions as mediated by polyphenols. Owing to the high binding affinity of phenolic motifs present at the surface, these particles allow for the subsequent deposition of various materials (i.e., organic, inorganic, and hybrid components), producing a variety of monodisperse functional particles. Moreover, the solvent-dependent disassembly of the supramolecular networks enables their removal, generating a wide range of corresponding hollow structures including capsules and yolk-shell structures. The versatility of these supramolecular networks, combined with their negligible cytotoxicity provides a pathway for the rational design of a range of particle systems (including core-shell, hollow, and yolk-shell) with potential in biomedical and environmental applications.

16.
ACS Nano ; 14(10): 12972-12981, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-32997490

RESUMO

Intracellular delivery of proteins is a promising strategy for regulating cellular behavior and therefore has attracted interest for biomedical applications. Despite the emergence of various nanoparticle-based intracellular delivery approaches, it remains challenging to engineer a versatile delivery system capable of responding to various physiological triggers without the need for complex chemical synthesis of the delivery system. Herein, we develop a template-mediated supramolecular assembly strategy to synthesize protein-polyphenol nanoparticles (NPs) capable of endosomal escape and subsequent protein release in the cytosol. These NPs are stable in serum and undergo surface charge reversal from negative to positive in acidic environments, leading to spontaneous endosomal escape. In the cytosol, endogenous small peptides and amino acids with relatively high charge densities, such as glutathione, trigger NP disassembly through competitive supramolecular interactions, thereby releasing functional bioactive proteins, as validated using cytochrome C and ß-galactosidase. The versatility of the present strategy in terms of nanoparticle size, protein type, and functional protein delivery makes this a promising platform for potential application in the field of protein therapeutics.


Assuntos
Nanopartículas , Polifenóis , Endossomos , Peptídeos , Proteínas
17.
Acc Chem Res ; 53(7): 1269-1278, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32567830

RESUMO

Polyphenols are naturally occurring compounds that are ubiquitous in plants and display a spectrum of physical, chemical, and biological properties. For example, they are antioxidants, have therapeutic properties, absorb UV radiation, and complex with metal ions. Additionally, polyphenols display high adherence, which has been exploited for assembling nanostructured materials. We previously reviewed the assembly of different phenolic materials and their applications (Angew. Chem. Int. Ed. 2019, 58, 1904-1927); however, there is a need for a summary of the fundamental interactions that govern the assembly, stability, and function of polyphenol-based materials. A detailed understanding of interactions between polyphenols and various other building blocks will facilitate the rational design and assembly of advanced polyphenol particles for specific applications. This Account discusses how different interactions and bonding (i.e., hydrogen, π, hydrophobic, metal coordination, covalent, and electrostatic) can be leveraged to assemble and stabilize polyphenol-based particles for diverse applications. In polyphenol-mediated assembly strategies, the polyphenols typically exert more than one type of stabilizing attractive force. However, one interaction often dominates the assembly process and dictates the physicochemical behavior of the particles, which in turn influences potential applications. This Account is thus divided into sections that each focus on a key interaction with relevant examples of applications to highlight structure-function relationships. For example, metal coordination generally becomes weaker at lower pH, which makes it possible to engineer metal-phenolic materials with a pH-responsive disassembly profile suitable for drug delivery. Engineered particles, such as hollow capsules, mesoporous and core-shell particles, and self-assembled nanoparticles are some of the systems that are covered to highlight how polyphenols interact with other building blocks and therefore make up the major focus of this Account. Some of the applications of these materials exemplified in this Account include drug delivery, catalysis, environmental remediation, and forensics. Finally, a perspective is provided on the current challenges and trends in polyphenol-mediated particle assembly, and viable near-term strategies for further elucidating the interplay of various competing interactions in particle formation are discussed. This Account is also expected to serve as a reference to guide fundamental research and facilitate the rational design of polyphenol-based materials for diverse emerging applications.

18.
Angew Chem Int Ed Engl ; 59(36): 15618-15625, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32115863

RESUMO

Functional materials composed of proteins have attracted much interest owing to the inherent and diverse functionality of proteins. However, establishing general techniques for assembling proteins into nanomaterials is challenging owing to the complex physicochemical nature and potential denaturation of proteins. Here, a simple, versatile strategy is introduced to fabricate functional protein assemblies through the interfacial assembly of proteins and polyphenols (e.g., tannic acid) on various substrates (organic, inorganic, and biological). The dominant interactions (hydrogen-bonding, hydrophobic, and ionic) between the proteins and tannic acid were elucidated; most proteins undergo multiple noncovalent stabilizing interactions with polyphenols, which can be used to engineer responsiveness into the assemblies. The proteins retain their structure and function within the assemblies, thereby enabling their use in various applications (e.g., catalysis, fluorescence imaging, and cell targeting).

19.
Mater Sci Eng C Mater Biol Appl ; 106: 110280, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753359

RESUMO

A faithful reconstruction of the native cellular microenvironment is instrumental for tissue engineering. Macromolecular crowding (MMC) empowers cells to deposit their own extracellular matrix (ECM) in greater amounts, and thus contributes to building tissue-specific complex microenvironments in vitro. Dextran sulfate (DxS, 500 kDa), a semi-synthetic sulfated polyglucose, was shown previously at a fractional volume occupancy (FVO) of 5.2% (v/v; 100 µg/ml) to act as a potent molecular crowding agent in vitro. When added to human mesenchymal stromal cell (MSC) cultures, DxS enhanced fibronectin and collagen I deposition several-fold also at concentrations with negligible FVO (<1% v/v). In a cell-free system, incubation of culture media supplemented with fetal bovine serum (FBS), purified fibronectin or collagen I with DxS led to a co-deposition of respective components, exhibiting a similar granular pattern as observed in cell culture. Aggregation of FBS components, fibronectin or collagen I with DxS was confirmed by dynamic light scattering, where an increase in hydrodynamic radius in the respective mixtures was observed. FBS- and fibronectin aggregates could be dissociated with increasing salt concentrations, indicating electrostatic forces to be responsible for the aggregation. Conversely, collagen I-DxS aggregates increased in size with increasing ion concentration, likely caused by charge screening of collagen I, which is net negatively charged at neutral pH, thus permitting weaker intermolecular interactions to occur. The incorporation of DxS into the ECM resulted in altered ECM topography and stiffness. DxS-supplemented cultures exhibited potentiated bioactivity, such as enhanced adipogenic and especially osteogenic differentiation under inductive conditions. We propose an alternative mechanism by which DxS drives ECM deposition via aggregation, and in an independent manner from MMC. A deeper understanding of the underlying mechanism will enable optimized engineering approaches for ECM-rich tissue constructs.


Assuntos
Meios de Cultura/química , Sulfato de Dextrana/química , Matriz Extracelular/metabolismo , Adipogenia/efeitos dos fármacos , Células da Medula Óssea/citologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/metabolismo , Meios de Cultura/farmacologia , Matriz Extracelular/química , Fibronectinas/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese/efeitos dos fármacos , Eletricidade Estática
20.
J Am Chem Soc ; 142(1): 335-341, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31851509

RESUMO

Mesoporous metal-organic networks have attracted widespread interest owing to their potential applications in diverse fields including gas storage, separations, catalysis, and drug delivery. Despite recent advances, the synthesis of metal-organic networks with large and ordered mesochannels (>20 nm), which are important for loading, separating, and releasing macromolecules, remains a challenge. Herein, we report a templating strategy using sacrificial double cubic network polymer cubosomes (Im3̅m) to synthesize ordered mesoporous metal-phenolic particles (meso-MPN particles) with a large-pore (∼40 nm) single cubic network (Pm3̅m). We demonstrate that the large-pore network and the phenolic groups in the meso-MPN particles enable high loadings of various proteins (e.g., horseradish peroxidase (HRP), bovine hemoglobin, immunoglobulin G, and glucose oxidase (GOx)), which have different shapes, charges, and sizes (i.e., molecular weights spanning 44-160 kDa). For example, GOx loading in the meso-MPN particles was 362 mg g-1, which is ∼6-fold higher than the amount loaded in commercially available SiO2 particles with an average pore size of 50 nm. Furthermore, we show that HRP, when loaded in the meso-MPN particles (486 mg g-1), retained ∼82% activity of free HRP in solution and can be recycled at least five times with a minimal (∼13%) decrease in HRP activity, which exceeds HRP performance in 50 nm pore SiO2 particles (∼36% retained activity and ∼30% activity loss when recycled five times). Considering the wide selection of naturally abundant polyphenols (>8000 species) and metal ions available, the present cubosome-enabled strategy is expected to provide new avenues for designing a range of meso-MPN particles for various applications.

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