self-assembly

自组装
  • 文章类型: Journal Article
    具有可控几何形状的DNA纳米管具有广泛的跨学科应用。当制备不同宽度或不同手性的DNA纳米管时,现有的方法需要反复设计和合成特定的DNA序列,这可能是昂贵和费力的。这里,我们提出了一种嵌入剂辅助的DNA瓦片组装方法,该方法可以使用相同的DNA链生产不同宽度和手性的DNA纳米管。通过在组装过程中调节嵌入剂的浓度,可以调节DNA瓦片的扭曲方向和程度,导致形成具有可控宽度和手性的DNA纳米管。此外,通过引入额外的嵌入剂和二次退火,右旋纳米管可以重新配置成不同的左旋纳米管。我们期望这种方法可以普遍应用于调节各种DNA瓦片和其他手性材料的自组装途径,推进DNA瓷砖组装的景观。
    DNA nanotubes with controllable geometries hold a wide range of interdisciplinary applications. When preparing DNA nanotubes of varying widths or distinct chirality, existing methods require repeatedly designing and synthesizing specific DNA sequences, which can be costly and laborious. Here, we proposed an intercalator-assisted DNA tile assembly method which enables the production of DNA nanotubes of diverse widths and chirality using identical DNA strands. Through adjusting the concentration of intercalators during assembly, the twisting direction and extent of DNA tiles could be modulated, leading to the formation of DNA nanotubes featuring controllable widths and chirality. Moreover, through introducing additional intercalators and secondary annealing, right-handed nanotubes could be reconfigured into distinct left-handed nanotubes. We expect that this method could be universally applied to modulating the self-assembly pathways of various DNA tiles and other chiral materials, advancing the landscape of DNA tile assembly.
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  • 文章类型: Journal Article
    受到活性位点不足和机械强度受限的限制,设计具有高活性和延展性的可靠和可穿戴气体传感器仍然是检测有害气体的挑战。在这项工作中,实施热诱导和溶剂辅助的氧阴离子蚀刻策略,用于在刚性微孔Cu基金属有机骨架(称为CuM)中选择性开孔。然后,通过接枝在富含缺陷的Cu-BTC表面上的PVP中的羰基氧原子与MXene上的表面官能羟基之间的协同氢键相互作用,使导电的CuM/MXene气凝胶自组装。最终实现了使用CuM/MXene气凝胶杂交海藻酸钠水凝胶的柔性NO2传感性能,表现出非凡的灵敏度(S=52.47对50ppm的NO2),良好的选择性,和快速响应/恢复时间(0.9/4.5s)在室温下。与商用传感器相比,相对误差小于7.7%,从而在监测有毒和有害气体方面表现出巨大的应用潜力。这项工作不仅为指导合理合成MOF复合材料的理想结构模型提供了见解,而且还激发了用于潜在多场景应用的高性能柔性气体传感器的开发。
    Limited by insufficient active sites and restricted mechanical strength, designing reliable and wearable gas sensors with high activity and ductility remains a challenge for detecting hazardous gases. In this work, a thermally induced and solvent-assisted oxyanion etching strategy was implemented for selective pore opening in a rigid microporous Cu-based metal-organic framework (referred to as CuM). A conductive CuM/MXene aerogel was then self-assembled through cooperative hydrogen bonding interactions between the carbonyl oxygen atom in PVP grafted on the surface of defect-rich Cu-BTC and the surface functional hydroxyl group on MXene. A flexible NO2 sensing performance using the CuM/MXene aerogel hybridized sodium alginate hydrogel is finally achieved, demonstrating extraordinary sensitivity (S = 52.47 toward 50 ppm of NO2), good selectivity, and rapid response/recovery time (0.9/4.5 s) at room temperature. Compared with commercial sensors, the relative error is less than 7.7%, thereby exhibiting significant potential for application in monitoring toxic and harmful gases. This work not only provides insights for guiding rational synthesis of ideal structure models from MOF composites but also inspires the development of high-performance flexible gas sensors for potential multiscenario applications.
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  • 文章类型: Journal Article
    Reflecin是一种固有的无序蛋白(IDP),以其基于其组装诱导的渗透特性来调节头足类动物的生物光子伪装的能力而闻名。其可逆的自组装成离散的,已知大小控制的簇和凝聚的液滴敏感地依赖于净蛋白质电荷,使反射素刺激响应pH,磷酸化,和电场。尽管做出了相当大的努力来描述这种行为,反射组件的详细物理机制尚未完全理解。这里,我们追求一个粗粒度的分子理解反射组装使用实验和模拟相结合。我们假设反射组装和相行为可以从一个非常简单的胶体模型中解释,其中单个蛋白质单体通过短程吸引和长程排斥(SA-LR)对电势有效地相互作用。我们从小角度X射线散射测量参数化了反射A1的粗粒度SA-LR相互作用电位,然后使用Gouy-Chapman理论将其扩展到pH范围,以模拟单体-单体的静电相互作用。然后将pH依赖性SA-LR相互作用用于反射组装的分子动力学模拟,它成功地捕获了反射的许多定性特征,包括pH依赖性的离散大小的纳米团簇的形成和在高pH下的液-液相分离,产生了一个推定的反射相图。重要的是,我们发现在低pH下,尺寸控制的反射团簇是平衡组件,动态交换蛋白质单体以保持平衡的大小分布。这些发现提供了对反射素平衡组装的机械理解,并建议胶体尺度模型捕获关键驱动力和相互作用来解释天然反射行为的热力学方面。此外,本研究中SA-LR相互作用的成功证明了对一系列IDP中的相互作用和现象进行胶体解释的潜力。
    Reflectin is an intrinsically disordered protein (IDP) known for its ability to modulate the biophotonic camouflage of cephalopods based on its assembly-induced osmotic properties. Its reversible self-assembly into discrete, size-controlled clusters and condensed droplets are known to depend sensitively on the net protein charge, making reflectin stimuli-responsive to pH, phosphorylation, and electric fields. Despite considerable efforts to characterize this behavior, the detailed physical mechanisms of reflectin\'s assembly are yet fully understood. Here, we pursue a coarse-grained molecular understanding of reflectin assembly using a combination of experiments and simulations. We hypothesize that reflectin assembly and phase behavior can be explained from a remarkably simple colloidal model whereby individual protein monomers effectively interact via a short-range attractive and long-range repulsive (SA-LR) pair potential. We parameterize a coarse-grained SA-LR interaction potential for reflectin A1 from small angle X-ray scattering measurements, and then extend it to a range of pH using Gouy-Chapman theory to model monomer-monomer electrostatic interactions. The pH-dependent SA-LR interaction is then used in molecular dynamics simulations of reflectin assembly, which successfully capture a number of qualitative features of reflectin, including pH-dependent formation of discrete-sized nanoclusters and liquid-liquid phase separation at high pH, resulting in a putative phase diagram for reflectin. Importantly, we find that at low pH, size-controlled reflectin clusters are equilibrium assemblies, which dynamically exchange protein monomers to maintain an equilibrium size distribution. These findings provide a mechanistic understanding of the equilibrium assembly of reflectin, and suggest that colloidal-scale models capture key driving forces and interactions to explain thermodynamic aspects of native reflectin behavior. Furthermore, the success of SA-LR interactions presented in this study demonstrates the potential of a colloidal interpretation of interactions and phenomena in a range of IDPs.
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  • 文章类型: Journal Article
    淀粉样蛋白样肽纤维发射固有荧光的能力使得能够研究它们的形成,通过时间分辨荧光分析的稳定性和硬化,不需要额外的插层染料。这种方法允许使用最小的样品体积监测淀粉样肽聚集动力学,同时测试许多实验条件和分析物,提供快速和可重复的结果。适用于单独或用不同长度的PEG(聚乙二醇)部分衍生的芳香族六肽F6的分析程序,表明聚集成大的各向异性结构与初始单体浓度负相关,并且依赖于带电的N-和C-末端的存在。聚乙二醇化降低了骨料硬化的程度,可能是通过保留水,并且总体上影响骨料的最终结构特性。
    The capability of amyloid-like peptide fibers to emit intrinsic-fluorescence enables the study of their formation, stability and hardening through time-resolved fluorescence analysis, without the need for additional intercalating dyes. This approach allows the monitoring of amyloid-like peptides aggregation kinetics using minimal sample volumes, and the simultaneous testing of numerous experimental conditions and analytes, offering rapid and reproducible results. The analytical procedure applied to the aromatic hexapeptide F6, alone or derivatized with PEG (polyethylene glycol) moiety of different lengths, suggests that aggregation into large anisotropic structures negatively correlates with initial monomer concentration and relies on the presence of charged N- and C-termini. PEGylation reduces the extent of aggregates hardening, possibly by retaining water, and overall impacts the final structural properties of the aggregates.
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  • 文章类型: Journal Article
    合成了一种六环冠醚型支柱[5]芳烃,并且五个环氧乙烷回路位于腔外,不受温度变化的影响,这通过DMSO-d6和CDCl3中的变温NMR实验以及CDCl3中的2D1H-1HNOESY实验得到了证实。六环柱[5]-冠还显示出比常规烷氧基柱[5]芳烃更高的主客体与双(吡啶)衍生物的结合能力,这通过1HNMR滴定光谱实验在丙酮-d6/CDCl3(1:1)和室温下在CHCl3中进行的UV-vis滴定实验进行了说明。通过在CD2Cl2/甲醇-d4(9:1)中的1HNMR滴定光谱实验,外围的五个苯并冠醚能够结合金属阳离子。
    A six-cyclic crown ether-type pillar[5]arene was synthesized, and the five ethylene oxide loops were located outside the cavity and not affected by temperature changes which was confirmed by variable-temperature NMR experiment in DMSO-d6 and CDCl3 and 2D 1H-1H NOESY experiment in CDCl3. The six-cyclic pillar[5]-crown also showed greater binding ability of host-guest with bis(pyridinium) derivatives than conventional alkoxy pillar[5]arenes that illustrated through 1H NMR titration spectroscopic experiment in acetone-d6/CDCl3 (1:1) and UV-vis titration experiments in CHCl3 at room temperature. The five benzocrown ethers at the periphery were able to bind metal cations by 1H NMR titration spectroscopic experiment in CD2Cl2/methanol-d4(9:1).
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  • 文章类型: Journal Article
    基于脂质的纳米载体已广泛用于皮肤护理制剂中水不溶性活性成分的溶解和皮肤递送。然而,它们的实际应用往往受到结构不稳定性的限制,导致活性物质的过早释放和降解。在这里,我们提出了高度坚固的多层纳米囊泡,通过水解胶原蛋白肽的单层囊泡的多离子自组装制备,以稳定全反式视黄醇并增强其皮肤递送。我们的结果表明,增强的多层结构在极端恶劣的条件下大大提高了分散稳定性,像冻融循环,并稳定包封的视黄醇。有趣的是,这些多层囊泡对人真皮成纤维细胞的细胞毒性明显低于单层囊泡,可能是由于它们的单位重量颗粒数较小,最大限度地减少对细胞膜的潜在破坏。在人造皮肤模型中,负载视黄醇的多层囊泡有效上调胶原相关基因表达,同时抑制金属蛋白酶的合成。这些发现表明,强大的多层囊泡可以作为有效的纳米载体,用于在皮肤应用中有效递送和稳定生物活性化合物。
    Lipid-based nanocarriers have been extensively utilized for the solubilization and cutaneous delivery of water-insoluble active ingredients in skincare formulations. However, their practical application is often limited by structural instability, leading to premature release and degradation of actives. Here we present highly robust multilamellar nanovesicles, prepared by the polyionic self-assembly of unilamellar vesicles with hydrolyzed collagen peptides, to stabilize all-trans-retinol and enhance its cutaneous delivery. Our results reveal that the reinforced multilayer structure substantially enhances dispersion stability under extremely harsh conditions, like freeze-thaw cycles, and stabilizes the encapsulated retinol. Interestingly, these multilamellar vesicles exhibit significantly lower cytotoxicity to human dermal fibroblasts than their unilamellar counterparts, likely due to their smaller particle number per weight, minimizing potential disruptions to cellular membranes. In artificial skin models, retinol-loaded multilamellar vesicles effectively upregulate collagen-related gene expression while suppressing the synthesis of metalloproteinases. These findings suggest that the robust multilamellar vesicles can serve as effective nanocarriers for the efficient delivery and stabilization of bioactive compounds in cutaneous applications.
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  • 文章类型: Journal Article
    硫属铅胶体量子点由于其带隙可调性和强吸收,是最有前途的材料之一,可以彻底改变短波长红外光学领域。通过将这些量子点自组装成有序的超晶格,可以实现接近批量对应物的迁移率,同时仍保留其原始光学特性。最近的文献主要集中在基于PbSe的超晶格上,但是PbS量子点有几个优点,包括更高的稳定性。在这项工作中,我们展示了PbS量子点的高度有序的3D超晶格,具有高达200nm的可调厚度和高相干有序,平面内和沿厚度。我们表明,我们可以成功地在整个薄膜中交换配体,而不会影响排序。作为离子凝胶门控场效应晶体管的活性材料的超晶格可实现高达220cm2V-1s-1的电子迁移率。为了进一步提高器件性能,我们用PbI2进行了沉积后钝化,显着降低了亚阈值摆动,使其达到玻尔兹曼极限。我们认为这是一个重要的概念证明,表明有可能克服量子点超晶格中的高陷阱密度问题,从而使其能够在光电器件中应用。
    Lead chalcogenide colloidal quantum dots are one of the most promising materials to revolutionize the field of short-wavelength infrared optoelectronics due to their bandgap tunability and strong absorption. By self-assembling these quantum dots into ordered superlattices, mobilities approaching those of the bulk counterparts can be achieved while still retaining their original optical properties. The recent literature focused mostly on PbSe-based superlattices, but PbS quantum dots have several advantages, including higher stability. In this work, we demonstrate highly ordered 3D superlattices of PbS quantum dots with tunable thickness up to 200 nm and high coherent ordering, both in-plane and along the thickness. We show that we can successfully exchange the ligands throughout the film without compromising the ordering. The superlattices as the active material of an ion gel-gated field-effect transistor achieve electron mobilities up to 220 cm2 V-1 s-1. To further improve the device performance, we performed a postdeposition passivation with PbI2, which noticeably reduced the subthreshold swing making it reach the Boltzmann limit. We believe this is an important proof of concept showing that it is possible to overcome the problem of high trap densities in quantum dot superlattices enabling their application in optoelectronic devices.
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  • 文章类型: Journal Article
    白色罗马鹅(Anseranserdomesticus)的羽毛,由定向的圆锥形小球组成,涂有腺体分泌的精制油,以保持表面游泳的长期非润湿性能。鹅习惯于用扁平的钞票梳理羽毛,以防它们被亲油性物质污染,在此期间,两亲性唾液在barbulles上扩散,极大地损害了它们的表面疏水性,并允许被捕获的污染物通过水流各向异性地自我清洁。特别是,鹅羽毛的超疏水行为也得到了恢复。生物灵感来自白色罗马鹅的可切换各向异性自清洁功能,超疏水单向倾斜锥形结构是通过整合可扩展的胶体自组装技术和胶体光刻方法来设计的。方向滑动特性对形状的依赖性,倾角,本研究系统地研究了圆锥形结构的尺寸。此外,苏丹蓝II/水(0.01%)的分离性能证明了它们可切换的各向异性自清洁功能。白色罗马鹅羽毛风格的涂料无疑为开发需要定向运输和液体收集的创新应用提供了新概念。
    White Roman goose (Anser anser domesticus) feathers, comprised of oriented conical barbules, are coated with gland-secreted preening oils to maintain a long-term nonwetting performance for surface swimming. The geese are accustomed to combing their plumages with flat bills in case they are contaminated with oleophilic substances, during which the amphiphilic saliva spread over the barbules greatly impairs their surface hydrophobicities and allows the trapped contaminants to be anisotropically self-cleaned by water flows. Particularly, the superhydrophobic behaviors of the goose feathers are recovered as well. Bioinspired by the switchable anisotropic self-cleaning functionality of white Roman geese, superhydrophobic unidirectionally inclined conical structures are engineered through the integration of a scalable colloidal self-assembly technology and a colloidal lithographic approach. The dependence of directional sliding properties on the shape, inclination angle, and size of conical structures is systematically investigated in this research. Moreover, their switchable anisotropic self-cleaning functionalities are demonstrated by Sudan blue II/water (0.01%) separation performances. The white Roman goose feather-inspired coatings undoubtedly offer a new concept for developing innovative applications that require directional transportation and the collection of liquids.
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  • 文章类型: Journal Article
    超分子材料已经使用广泛的相互作用进行组装,包括疏水效应,DNA碱基配对,和氢键。具体来说,具有疏水性结构单元的DNA两亲物根据两个嵌段的长度和组成自组装成不同的形态。在这里,我们利用不同超分子相互作用的正交性-疏水效应,Watson-Crick-Franklin碱基配对和RNA接吻环-在纳米和微米尺度上创建具有受控形态的分层自组装体。通过碱基配对组装导致杂种的形成,具有高刚度和自修复性能的多相水凝胶。通过疏水核心相互作用的组装给出各向异性,离散组件,其中具有一个序列的DNA纤维终止于具有不同序列的DNA球体。这项工作为自下而上构建基于DNA的材料开辟了新的途径,在药物输送中具有广阔的应用前景,组织工程,以及从最少的组件阵列中创建复杂的DNA结构。
    Supramolecular materials have been assembled using a wide range of interactions, including the hydrophobic effect, DNA base-pairing, and hydrogen bonding. Specifically, DNA amphiphiles with a hydrophobic building block self-assemble into diverse morphologies depending on the length and composition of both blocks. Herein, we take advantage of the orthogonality of different supramolecular interactions - the hydrophobic effect, Watson-Crick-Franklin base pairing and RNA kissing loops - to create hierarchical self-assemblies with controlled morphologies on both the nanometer and the micrometer scales. Assembly through base-pairing leads to the formation of hybrid, multi-phasic hydrogels with high stiffness and self-healing properties. Assembly via hydrophobic core interactions gives anisotropic, discrete assemblies, where DNA fibers with one sequence are terminated with DNA spheres bearing different sequences. This work opens new avenues for the bottom-up construction of DNA-based materials, with promising applications in drug delivery, tissue engineering, and the creation of complex DNA structures from a minimum array of components.
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  • 文章类型: Journal Article
    cGAS(环GMP-AMP合酶)-STING(干扰素基因的刺激物)途径通过感测从细胞核和线粒体泄漏的胞质DNA片段来促进抗肿瘤免疫反应。在这里,我们设计了一种高电荷的钌光敏剂(Ru1),其β-咔啉生物碱衍生物作为配体,用于光活化cGAS-STING途径。由于多个非共价分子间相互作用的形成,Ru1可以自组装成无载体纳米粒子(NPs)。通过引入三苯基膦取代基,Ru1可以靶向和光损伤线粒体DNA(mtDNA),导致细胞质DNA泄漏,从而激活cGAS-STING途径。最后,Ru1NP显示出有效的抗肿瘤作用,并在体内引发强烈的免疫反应。总之,我们报道了第一个自组装mtDNA靶向光敏剂,可以有效激活cGAS-STING途径,从而为新的光免疫治疗剂的设计提供了创新。
    The cGAS (cyclic GMP-AMP synthase)-STING (stimulator of interferon genes) pathway promotes antitumor immune responses by sensing cytosolic DNA fragments leaked from nucleus and mitochondria. Herein, we designed a highly charged ruthenium photosensitizer (Ru1) with a β-carboline alkaloid derivative as the ligand for photo-activating of the cGAS-STING pathway. Due to the formation of multiple non-covalent intermolecular interactions, Ru1 can self-assemble into carrier-free nanoparticles (NPs). By incorporating the triphenylphosphine substituents, Ru1 can target and photo-damage mitochondrial DNA (mtDNA) to cause the cytoplasmic DNA leakage to activate the cGAS-STING pathway. Finally, Ru1 NPs show potent antitumor effects and elicit intense immune responses in vivo. In conclusion, we report the first self-assembling mtDNA-targeted photosensitizer, which can effectively activate the cGAS-STING pathway, thus providing innovations for the design of new photo-immunotherapeutic agents.
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