self-assembly

自组装
  • 文章类型: Journal Article
    以线性两亲性嵌段共聚物为模板是制备介孔资料的重要办法。然而,获得的组件通常对合成条件敏感,这阻碍了在某些环境中制备这种介孔材料。在这里,我们报告了一种通用策略,该策略使用一种金属氧化物(TiO2,ZrO2,WO3,CeO2)制备介孔金属氧化物纳米纤维(NFs),或两种(TiO2/WO3,TiO2/ZrO2,TiO2/CeO2)和三种(TiO2/WO3/CuO)金属氧化物作为复合物。模板由修饰的β-环糊精作为大分子的中心组成,该大分子依次连接到聚苯乙烯嵌段上,聚(丙烯酸),和聚(环氧乙烷)。在静电纺丝条件下,形成稳定的单分子胶束,并有效地与金属离子共组装形成纤维状纳米结构。如各种表征方法所示,合成的TiO2及其衍生的复合NFs在煅烧后保持笔直和连续的纤维结构,和TiO2NFs表现出直径为10.8nm的均匀中孔和143.3m2g-1的大Brunauer-Emmett-Teller表面积。受益于独特的结构,修改后仍然存在,Pt修饰的介孔TiO2NFs在可见光光催化降解四环素方面表现出优异的能力,这是优于商业P25催化剂。这项研究揭示了制备纤维状介孔金属氧化物的有希望的策略。
    The use of linear amphiphilic block copolymers as templates is an important method for the preparation of mesoporous materials. However, the obtained assemblies are usually sensitive to synthetic conditions, which impedes the preparation of such mesoporous materials in certain environments. Herein, we report a universal strategy applying an amphiphilic multi-arm triblock copolymer in the preparation of mesoporous metal oxide nanofibers (NFs) using one metal oxide (TiO2, ZrO2, WO3, CeO2), or two (TiO2/WO3, TiO2/ZrO2, TiO2/CeO2) and three (TiO2/WO3/CuO) metal oxides as composites. The template consists of modified β-cyclodextrin as the center of the macromolecule which is attached sequentially to a block of polystyrene, poly(acrylic acid), and poly(ethylene oxide). Under electrospinning conditions, stable unimolecular micelles are formed and effectively co-assemble with metal ions to form fibrous nanostructures. As indicated by various characterization methods, the synthesized TiO2 and its derived composite NFs maintain a straight and continuous fibrous structure after calcination, and TiO2 NFs exhibit uniform mesopores of 10.8 nm in diameter and a large Brunauer-Emmett-Teller surface area of 143.3 m2 g-1. Benefiting from the characteristic structure, still present after modification, Pt-decorated mesoporous TiO2 NFs display excellent ability in the visible-light photocatalytic degradation of tetracycline, which is superior to the commercial P25 catalyst. This study reveals a promising strategy for the preparation of fibrous mesoporous metal oxides.
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  • 文章类型: Journal Article
    利用嵌段共聚物(BCP)自组装的纳米图案化方法由于其分子精度和高分辨率而对半导体制造具有吸引力。接枝聚合物刷在提供有利于BCP定向控制的中性表面方面起着至关重要的作用。这些刷子创造了一个非优先底物,允许润湿来自BCP的每个块的不同化学物质。这垂直对齐BCP自组装晶格以产生可用于半导体纳米加工的图案。在这次审查中,我们的目标是探索用于将底物和BCP界面调整为中性模板的各种方法。这篇评论从历史角度出发,研究了为实现底物中性而开发的聚合物刷方法。我们将这些方法分为共聚物和共混均聚物方法。获得中性基材的早期尝试使用由来自每个嵌段的单体组成的末端接枝的无规共聚物。这演变成侧基接枝链,交联垫,和块cooligomer刷。在链架构的扩充中,开发了均聚物共混物作为一种简便的方法,其中将具有每种化学物质的聚合物链混合并接枝到基材上。由于化学不相容链的宏观相分离,这在很大程度上被认为是具有挑战性的。然而,创新的方法,如顺序接枝和BCP增容剂被用来规避这个问题。在中立性和可行性的背景下讨论了每种方法的优点和挑战。
    Nanopatterning methods utilizing block copolymer (BCP) self-assembly are attractive for semiconductor fabrication due to their molecular precision and high resolution. Grafted polymer brushes play a crucial role in providing a neutral surface conducive for the orientational control of BCPs. These brushes create a non-preferential substrate, allowing wetting of the distinct chemistries from each block of the BCP. This vertically aligns the BCP self-assembled lattice to create patterns that are useful for semiconductor nanofabrication. In this review, we aim to explore various methods used to tune the substrate and BCP interface toward a neutral template. This review takes a historical perspective on the polymer brush methods developed to achieve substrate neutrality. We divide the approaches into copolymer and blended homopolymer methods. Early attempts to obtain neutral substrates utilized end-grafted random copolymers that consisted of monomers from each block. This evolved into side-group-grafted chains, cross-linked mats, and block cooligomer brushes. Amidst the augmentation of the chain architecture, homopolymer blends were developed as a facile method where polymer chains with each chemistry were mixed and grafted onto the substrate. This was largely believed to be challenging due to the macrophase separation of the chemically incompatible chains. However, innovative methods such as sequential grafting and BCP compatibilizers were utilized to circumvent this problem. The advantages and challenges of each method are discussed in the context of neutrality and feasibility.
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  • 文章类型: Journal Article
    急性肺损伤(ALI)仍然是一个重要的全球健康问题。需要新的治疗干预措施。在我们最新的研究中,我们率先使用D-甘露醇-铈-槲皮素/芦丁配位聚合物纳米颗粒(MCQ/RNP)作为ALI的潜在治疗方法。MCQ/RNP,其中整合了芦丁和槲皮素的治疗潜力和D-甘露醇的肺靶向,表现出非凡的功效。通过利用铈离子进行最佳纳米粒子组装,MCQ/RNP的平均尺寸小于160nm。令人印象深刻的是,这些纳米颗粒在抗氧化能力和生物相容性方面都优于常规治疗。此外,我们对LPS诱导的ALI小鼠的体内研究显示,肺组织炎症显著减轻.这项开创性的研究提出了MCQ/RNP作为ALI治疗中一种有前途的新方法。
    Acute lung injury (ALI) remains a significant global health issue, necessitating novel therapeutic interventions. In our latest study, we pioneered the use of D-mannitol-cerium-quercetin/rutin coordination polymer nanoparticles (MCQ/R NPs) as a potential treatment for ALI. The MCQ/R NPs, which integrate rutin and quercetin for their therapeutic potential and D-mannitol for its pulmonary targeting, displayed exceptional efficacy. By utilizing cerium ions for optimal nanoparticle assembly, the MCQ/R NPs demonstrated an average size of less than 160 nm. Impressively, these nanoparticles outperformed conventional treatments in both antioxidative capabilities and biocompatibility. Moreover, our in vivo studies on LPS-induced ALI mice showed a significant reduction in lung tissue inflammation. This groundbreaking research presents MCQ/R NPs as a promising new approach in ALI therapeutics.
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  • 文章类型: Journal Article
    构建肽以模拟异质蛋白如I型胶原在破译其功能和发病机理中起关键作用。然而,由于缺乏产生具有所需功能序列且没有同三聚体作用的稳定异源三聚体的能力,该领域的进展受到严重阻碍。我们在此开发了一组三嵌段肽,其可以组装成具有所需氨基酸的胶原模拟异源三聚体,并且不受同源三聚体的干扰。三嵌段肽包含一个中央胶原样阻断和两个带相反电荷的N/C末端阻断,显示同质三聚体形成的固有无能。具有互补末端带电序列的两个配对三嵌段肽之间的有利静电吸引迅速导致具有受控链组成的稳定异源三聚体。胶原蛋白样区块与两个末端区块的独立性赋予该系统在保持异源三聚体结构的同时掺入所需氨基酸序列的适应性。三嵌段肽提供了一种通用且强大的工具来模拟异源三聚体胶原蛋白的组成和功能,并且在模拟异质蛋白质的创新肽的设计中可能具有巨大潜力。
    The construction of peptides to mimic heterogeneous proteins such as type I collagen plays a pivotal role in deciphering their function and pathogenesis. However, progress in the field has been severely hampered by the lack of capability to create stable heterotrimers with desired functional sequences and without the effect of homotrimers. We have herein developed a set of triblock peptides that can assemble into collagen mimetic heterotrimers with desired amino acids and are free from the interference of homotrimers. The triblock peptides comprise a central collagen-like block and two oppositely charged N-/C-terminal blocks, which display inherent incompetency of homotrimer formation. The favorable electrostatic attraction between two paired triblock peptides with complementary terminal charged sequences promptly leads to stable heterotrimers with controlled chain composition. The independence of the collagen-like block from the two terminal blocks endows this system with the adaptability to incorporate desired amino acid sequences while maintaining the heterotrimer structure. The triblock peptides provide a versatile and robust tool to mimic the composition and function of heterotrimer collagen and may have great potential in the design of innovative peptides mimicking heterogeneous proteins.
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  • 文章类型: Journal Article
    α-突触核蛋白(AS)形成毒性寡聚物的主要成核过程是帕金森病病理原因的早期阶段。众所周知,铜影响该初级成核过程。虽然已经做出了巨大的努力来解决多晶型AS原纤维的结构,AS低聚物和铜结合AS低聚物在分子水平上的结构以及铜浓度对初级成核的影响是难以捉摸的。这里,我们提出并证明了AS初级成核的新分子机制途径,这些途径由不同的铜浓度和特定的铜结合位点调节。我们提出了在高和低铜浓度下以原子分辨率与不同铜结合位点结合的多态性AS二聚体,使用广泛的分子动力学模拟。我们的结果显示了依赖于铜浓度和铜结合位点的主要成核途径的复杂性。从更广泛的角度来看,我们的研究提出了一种新的策略来控制其他神经退行性疾病中其他毒性淀粉样蛋白寡聚体的主要成核。
    The primary nucleation process of α-synuclein (AS) that forms toxic oligomeric species is the early stage of the pathological cause of Parkinson\'s disease. It is well-known that copper influences this primary nucleation process. While significant efforts have been made to solve the structures of polymorphic AS fibrils, the structures of AS oligomers and the copper-bound AS oligomers at the molecular level and the effect of copper concentrations on the primary nucleation are elusive. Here, we propose and demonstrate new molecular mechanism pathways of primary nucleation of AS that are tuned by distinct copper concentrations and by a specific copper-binding site. We present the polymorphic AS dimers bound to different copper-binding sites at the atomic resolution in high- and low-copper concentrations, using extensive molecular dynamics simulations. Our results show the complexity of the primary nucleation pathways that rely on the copper concentrations and the copper binding site. From a broader perspective, our study proposes a new strategy to control the primary nucleation of other toxic amyloid oligomers in other neurodegenerative diseases.
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  • 文章类型: Journal Article
    人类免疫缺陷病毒从感染的宿主细胞出芽是通过修饰带有长链脂肪酸的结构蛋白诱导的,然后是它们锚定在细胞膜上。尽管已经开发了许多使用由各种刺激诱导的巨大单层囊泡(GUV)的模型出芽系统,仅使用合成分子构建GUV的人工病毒出芽系统仍然具有挑战性。在这里,我们报道了从GUV的脂质双层构建人工病毒衣壳出芽系统。使用辛基链作为烷基锚通过二硫键修饰β-环肽的C-末端。具有辛基链的β-环肽的自组装形成人工病毒衣壳聚集体。荧光成像和透射电子显微镜观察表明,将四甲基罗丹明(TMR)标记的带辛基链的β-环肽添加到GUV的外水相中可诱导衣壳封装的子囊泡的出芽。母体GUV的内部。相反,将TMR标记的带有辛基链的β-环肽封装在GUV的内水相中,会诱导衣壳封装的子囊泡从母体GUV的内部到外部的出芽。相反,将TMR标记的β-环肽添加到GUV几乎不诱导出芽。结果表明,GUV的膜流动性越高,通过添加烷基锚修饰的人工病毒衣壳,更有可能诱导出芽。在这项研究中开发的简单的病毒模拟材料,它们通过膜锚定脱落,可以提供对天然病毒从细胞出芽的机制的物理化学见解。
    仅使用合成分子构建GUV的人工病毒出芽系统仍然具有挑战性。这项研究首先表明,通过添加烷基锚修饰的人工病毒衣壳,可以诱导从外到内和从内到外的GUV出芽。
    The budding of human immunodeficiency virus from an infected host cell is induced by the modification of structural proteins bearing long-chain fatty acids, followed by their anchoring to the cell membrane. Although many model budding systems using giant unilamellar vesicles (GUVs) induced by various stimuli have been developed, constructing an artificial viral budding system of GUVs using only synthesized molecules remains challenging. Herein, we report the construction of an artificial viral capsid budding system from a lipid bilayer of GUV. The C-terminus of the β-annulus peptide was modified using an octyl chain as an alkyl anchor via a disulfide bond. The self-assembly of the β-annulus peptide with an octyl chain formed an artificial viral capsid aggregate. The fluorescence imaging and transmission electron microscopy observations revealed that the addition of the tetramethylrhodamine (TMR)-labeled octyl chain-bearing β-annulus peptide to the outer aqueous phase of GUV induced the budding of the capsid-encapsulated daughter vesicle outside-to-inside the mother GUV. Conversely, the encapsulation of the TMR-labeled octyl chain-bearing β-annulus peptide in the inner aqueous phase of GUV induced the budding of the capsid-encapsulated daughter vesicle inside-to-outside the mother GUV. Contrarily, the addition of the TMR-labeled β-annulus peptide to GUV barely induced budding. It was demonstrated that the higher the membrane fluidity of GUV, the more likely budding would be induced by the addition of the alkyl anchor-modified artificial viral capsid. The simple virus-mimicking material developed in this study, which buds off through membrane anchoring, can provide physicochemical insights into the mechanisms of natural viral budding from cells.
    Construction of an artificial viral budding system of GUVs using only synthesized molecules remains challenging. This study firstly demonstrates that budding outside-to-inside and inside-to-outside GUVs are induced by addition of alkyl anchor-modified artificial viral capsid.
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  • 文章类型: Journal Article
    具有高聚合度的丙烯酰胺聚合物广泛用于石油生产中。从微观层面研讨高聚合度丙烯酰胺聚合物的驱油机理具有主要意义。近年来,计算机分子模拟技术的快速发展,填补了宏观实验和理论的空白。该技术在聚合物体系的分子行为研究中得到了高度重视。在本文中,综述了分子模拟应用于高聚合度丙烯酰胺聚合物的研究进展。丙烯酰胺聚合物驱油的应用现状,聚合物驱油机理分析,阐述了分子模拟在丙烯酰胺线性和交联聚合物中的研究进展。最后,给出了丙烯酰胺聚合物研究的发展前景,并从仿真方向和仿真工具等方面提出了建议。
    Acrylamide polymers with a high degree of polymerization are widely used in petroleum production. It is of great significance to study the oil displacement mechanism of acrylamide polymers with a high degree of polymerization from the micro level. In recent years, the rapid development of computer molecular simulation technology has filed the gaps in macroscopic experiments and theories. This technology has been highly valued in the study of the molecular behaviour of polymer systems. In this paper, the research progress of molecular simulation applied to high-polymerization-degree acrylamide polymer is summarized. The application status of acrylamide polymer flooding, the analysis of polymer flooding mechanisms, and the research progress of molecular simulation in acrylamide linear and crosslinked polymers are expounded. Finally, the development prospect of acrylamide polymer research is given, and suggestions are put forward in terms of simulation direction and simulation tools.
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  • 文章类型: Journal Article
    在各种衬底上自下而上地制造超分子和自组装已经成为实现用于电子电路或传感器的纳米器件开发前景的极其相关的目标。该领域的一个分支是通过表面上的非共价相互作用驱动的功能分子组分的自组装,例如范德华(vdW)交互,氢键(HB),静电相互作用,等。,允许可以满足纳米工程概念要求的纳米结构的受控设计。在这种情况下,非共价相互作用提供了先前在吸附在表面上的几种分子系统中探索的机会,主要是由于它们的高度方向性,有利于有序结构的形成。在这里,通过将STM(扫描隧道显微镜)与理论计算相结合,我们回顾了一系列研究工作,揭示了在金属表面上配备官能团的分子着陆器驱动的自组装领域中使用的过程。结合这些过程对于研究人员推进由固体表面上的多个非共价相互作用驱动的超分子结构的自组装是必要的。
    The bottom-up fabrication of supramolecular and self-assembly on various substrates has become an extremely relevant goal to achieve prospects in the development of nanodevices for electronic circuitry or sensors. One of the branches of this field is the self-assembly of functional molecular components driven through non-covalent interactions on the surfaces, such as van der Waals (vdW) interactions, hydrogen bonding (HB), electrostatic interactions, etc., allowing the controlled design of nanostructures that can satisfy the requirements of nanoengineering concepts. In this context, non-covalent interactions present opportunities that have been previously explored in several molecular systems adsorbed on surfaces, primarily due to their highly directional nature which facilitates the formation of well-ordered structures. Herein, we review a series of research works by combining STM (scanning tunneling microscopy) with theoretical calculations, to reveal the processes used in the area of self-assembly driven by molecule Landers equipped with functional groups on the metallic surfaces. Combining these processes is necessary for researchers to advance the self-assembly of supramolecular architectures driven by multiple non-covalent interactions on solid surfaces.
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  • 文章类型: Journal Article
    在这项工作中,梳型均聚物以及热响应性低聚(乙二醇甲醚甲基丙烯酸酯)的梳型共聚物,OEGMA,具有各种链长(DEGMA,PEGMA500和含有2、9或19个重复乙二醇单元的PEGMA950,分别)通过自由基(共)聚合合成。对于共聚物,功能性疏水甲基丙烯酸缩水甘油酯(GMA)或惰性亲水N,选择N-二甲基丙烯酰胺(DMAM)作为共聚单体。通过尼罗红荧光探测研究了产品的自组装和热响应行为,比浊法,和动态光散射(DLS)。有趣的是,发现所有基于OEGMA的均聚物在水性介质中都表现出自组织的趋势,除了热响应性。临界聚集浓度(CAC)随着OEGMA大分子单体中重复环氧乙烷单元的数量而增加(发现均聚物PDEGMA的CAC为0.003、0.01和0.03%w/v,分别为PPEGMA500和PPEGMA950)。此外,共聚物在水性介质中的CAC受到引入疏水性GMA或亲水性DMAM单元的高度影响,导致更低或更高的值,分别。因此,对于富含GMA的PEGMA950共聚物,CAC降低至0.003%w/v,而对于富含DMAM的DEGMA共聚物,CAC增加至0.01%w/v。比浊法和DLS研究证明,聚合物的热敏感性受几个参数控制,例如OEGMA侧链中重复乙二醇基团的数量,疏水或亲水共聚单体的摩尔百分比,以及在聚合物水溶液中添加盐。因此,发现均聚物PDEGMA的浊点为23°C,对于DMAM最富的DEGMA共聚物,浊点增加到33.5°C。最后,在加热含GMA的共聚物与二氧化硅纳米粒子的水性混合物过夜时形成水凝胶是这些聚合物的功能特性的有力证据。
    In this work, comb homopolymers as well as comb-type copolymers of thermo-responsive oligo(ethylene glycol methyl ether methacrylate)s, OEGMAs, with various chain lengths (DEGMA, PEGMA500, and PEGMA950 containing 2, 9, or 19 repeating ethylene glycol units, respectively) were synthesized through free radical (co)polymerization. For the copolymers, either the functional hydrophobic glycidyl methacrylate (GMA) or the inert hydrophilic N,N-dimethylacrylamide (DMAM) were selected as comonomers. The self-assembly and thermo-responsive behavior of the products was investigated through Nile Red fluorescence probing, turbidimetry, and dynamic light scattering (DLS). Interestingly, it was found that all OEGMA-based homopolymers exhibit a tendency to self-organize in aqueous media, in addition to thermo-responsiveness. The critical aggregation concentration (CAC) increases with the number of repeating ethylene oxide units in the OEGMA macromonomers (CAC was found to be 0.003, 0.01, and 0.03% w/v for the homopolymers PDEGMA, PPEGMA500, and PPEGMA950, respectively). Moreover, the CAC of the copolymers in aqueous media is highly affected by the incorporation of hydrophobic GMA or hydrophilic DMAM units, leading to lower or higher values, respectively. Thus, the CAC decreases down to 0.003% w/v for the GMA-richest copolymer of PEGMA950, whereas CAC increases up to 0.01% w/v for the DMAM-richest copolymer of DEGMA. Turbidimetry and DLS studies proved that the thermo-sensitivity of the polymers is governed by several parameters such as the number of repeating ethylene glycol groups in the side chains of the OEGMAs, the molar percentage of the hydrophobic or hydrophilic comonomers, along with the addition of salts in the aqueous polymer solutions. Thus, the cloud point of the homopolymer PDEGMA was found at 23 °C and it increases to 33.5 °C for the DMAM-richest copolymer of DEGMA. Lastly, the formation of a hydrogel upon heating aqueous mixtures of the GMA-comprising copolymers with silica nanoparticles overnight is strong evidence of the functional character of these polymers.
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  • 文章类型: Journal Article
    天然产物的自组装聚集结构由于其简单的合成而获得了极大的兴趣,缺乏与载体相关的毒性,和优良的生物功效。然而,它们的组装机制及其穿越胃肠道(GI)屏障的能力仍不清楚。这篇综述总结了各种分子间非共价相互作用和聚集结构,2010年至2024年在WebofScience上索引的研究。对天然小分子及其超分子聚集体自组装行为的化学信息学分析揭示了组装的有利条件,辅助药物配方。此外,这篇综述探讨了大分子如多糖的自组装特性,蛋白质,和外泌体,强调它们在药物输送中的作用。还讨论了克服胃肠道屏障和提高药物生物利用度的策略。这项工作强调了天然产物在口服药物递送中的潜力,并为设计更有效的药物递送系统提供了见解。
    The self-assembling aggregated structures of natural products have gained significant interest due to their simple synthesis, lack of carrier-related toxicity, and excellent biological efficacy. However, the mechanisms of their assembly and their ability to traverse the gastrointestinal (GI) barrier remain unclear. This review summarizes various intermolecular non-covalent interactions and aggregated structures, drawing on research indexed in Web of Science from 2010 to 2024. Cheminformatics analysis of the self-assembly behaviors of natural small molecules and their supramolecular aggregates reveals assembly-favorable conditions, aiding drug formulation. Additionally, the review explores the self-assembly properties of macromolecules like polysaccharides, proteins, and exosomes, highlighting their role in drug delivery. Strategies to overcome gastrointestinal barriers and enhance drug bioavailability are also discussed. This work underscores the potential of natural products in oral drug delivery and offers insights for designing more effective drug delivery systems.
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