self‐assembly

  • 文章类型: Journal Article
    磁电材料由于其在磁场下产生电的能力而对于技术应用是高度期望的。在研究的各种类型的磁电材料中,他们的有机同行提供了一个机会来开发可处理的解决方案,灵活,轻量级,和可穿戴电子设备。然而,有一种罕见的解决方案可处理的选择,灵活,具有巨大技术兴趣的轻质磁电材料。设计了具有精确定位的结构形成和功能单元(电偶极子和磁自旋)的超分子支架,以使自组装导致功能单元组织。结构形成片段允许这些支架在非极性溶剂中自组装成分层有序的结构,创建纳米纤维有机凝胶网络。特别是,迄今为止,由该有机凝胶衍生的干凝胶表现出最高的磁电耦合系数(αME≈216mVOe-1cm-1)。这甚至大于通常设想的由压电聚合物和无机磁体制成的复合材料。这种单组分有机多铁性材料在室温下表现出铁电性(Tc≈46°C)和顺磁性。有了这个,证明了有效收集杂散磁场的可能性,这些杂散磁场在周围环境中大量可用,否则就会浪费掉。
    Magnetoelectric materials are highly desirable for technological applications due to their ability to produce electricity under a magnetic field. Among the various types of magnetoelectric materials studied, their organic counterparts provide an opportunity to develop solution-processable, flexible, lightweight, and wearable electronic devices. However, there is a rare choice of solution-processable, flexible, lightweight magnetoelectric materials which has tremendous technological interest. A supramolecular scaffold with precisely positioned structure-forming and functional units (electrical dipoles and magnetic spins) is designed so that self-assembly results in functional unit organization. Structure-forming segments allow these scaffolds to self-assemble into hierarchically ordered structures in nonpolar solvents, creating nanofibrous organogel networks. In particular, the xerogel derived from this organogel exhibits the highest magnetoelectric coupling coefficient (αME ≈ 216 mV Oe-1 cm-1) reported to date for organic materials. This is even greater than commonly envisioned composite materials made of piezoelectric polymers and inorganic magnets. This single-component organic multiferroic material displays ferroelectricity (Tc ≈ 46 °C) and paramagnetic behavior at room temperature. With this, it is demonstrated that the possibilities of effectively harvesting stray magnetic fields that are copiously available in the surroundings and wasted otherwise.
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  • 文章类型: Journal Article
    蛋白质组装是生物系统中必不可少的过程,蛋白质自组装成具有不同功能的复杂结构。灵感来自自然界对蛋白质组装的精细控制,科学家们一直在探索设计和组装蛋白质结构的方法,精确控制它们的拓扑和功能。实现这一目标的一种有希望的方法是通过金属配位,它利用金属结合基序来介导蛋白质-蛋白质相互作用,并以受控的化学计量和几何形状组装蛋白质复合物。金属配位为蛋白质组装和从头结构设计提供了模块化和可调的方法,其中金属离子充当分子胶,以特定方向将蛋白质亚基保持在一起。金属协调的蛋白质组装体在开发功能性金属蛋白酶方面显示出巨大的潜力,新型生物材料和集成药物递送系统。在这次审查中,提供了受益于金属配位的蛋白质装配的最新进展的概述,专注于不同维度的各种蛋白质排列,包括蛋白质寡聚物,蛋白质纳米笼和高阶蛋白质结构。此外,重点介绍了用于组装蛋白质结构并精确控制其特性的关键金属结合基序和策略。还讨论了金属介导的蛋白质组装体在生物技术和生物医学中的潜在应用。
    Protein assembly is an essential process in biological systems, where proteins self-assemble into complex structures with diverse functions. Inspired by the exquisite control over protein assembly in nature, scientists have been exploring ways to design and assemble protein structures with precise control over their topologies and functions. One promising approach for achieving this goal is through metal coordination, which utilizes metal-binding motifs to mediate protein-protein interactions and assemble protein complexes with controlled stoichiometry and geometry. Metal coordination provides a modular and tunable approach for protein assembly and de novo structure design, where the metal ion acts as a molecular glue that holds the protein subunits together in a specific orientation. Metal-coordinated protein assemblies have shown great potential for developing functional metalloproteinase, novel biomaterials and integrated drug delivery systems. In this review, an overview of the recent advances in protein assemblies benefited from metal coordination is provided, focusing on various protein arrangements in different dimensions including protein oligomers, protein nanocage and higher-order protein architectures. Moreover, the key metal-binding motifs and strategies used to assemble protein structures with precise control over their properties are highlighted. The potential applications of metal-mediated protein assemblies in biotechnology and biomedicine are also discussed.
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  • 文章类型: Journal Article
    随着人们对基于摩擦电的传感器的日益关注,从特定物质合成电介质层的研究逐渐兴起。尽管有许多带负电荷的摩擦材料,缺乏可合成的带正电荷的材料,造成研究空白。这项研究证明了共轭的分子设计,介孔,自组装片材通过自下而上的合成。将合成的薄片功能化以产生摩擦电纳米发电机。其大的比表面积,柔软度,和内部空间增加了实际接触面积,并为聚吡咯纳米颗粒提供了吸附位点。-COO官能团的掺入增强了正摩擦电性能,形成具有电荷俘获能力的介电层。与聚四氟乙烯(PTFE)接触时,这种结构提高了输出电压,在电荷注入后显示出显着的放大,衰减最小。作为一个示范,双层结构被用作实验者手臂上的触摸板来书写符号。这些信号被输入到一个创新的机器学习模型中,以解释作者的意图。此外,该设备连接到实时医疗服务的终端,提出了具有人工智能的可穿戴摩擦电传感器的实际应用。
    With the increasing focus on triboelectric-based sensors, research on synthesizing dielectric layers from specific substances is gradually emerging. Despite numerous negatively-charged triboelectric materials, there is a scarcity of synthesizable positively-charged materials, creating a research gap. This study demonstrates the molecular design of a conjugated, mesoporous, self-assembled sheet via bottom-up synthesis. The synthesized sheet is functionalized to create a triboelectric nanogenerator. Its large specific surface area, softness, and internal space increase the actual contact area and provide adsorption sites for polypyrrole nanoparticles. The incorporation of -COO functional group enhances positive triboelectric performance, forming a dielectric layer with charge-trapping capabilities. When contact with polytetrafluoroethylene (PTFE), this structure boosts the output voltage, showing significant amplification after charge injection with minimal decay. As a demonstration, the bilayer structure is applied as a touchpad on the experimenter\'s arm to write symbols. The signals are input into an innovative machine-learning model to interpret the writer\'s intent. Additionally, the device connects to a terminal for real-time medical services, suggesting practical applications for wearable triboelectric sensors with artificial intelligence.
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  • 文章类型: Journal Article
    基于间充质干细胞(MSC)的治疗为缺血性卒中的治疗提供了有希望的策略,由于缺乏长期的细胞追踪策略以及缺血区干细胞的低存活率,这仍然受到限制。在这里,双功能纳米探针,钴原卟啉诱导的纳米自组装(CPSP),已通过钴原卟啉IX(CoPP)聚集诱导的自组装策略开发,通过简单的溶剂蒸发驱动方法将CoPP和超顺磁性氧化铁(SPION)结合在一起。没有任何额外的载体材料,获得的CPSP具有良好的生物相容性和高比例的活性成分。CPSP中的SPION形成簇状结构,这种纳米自组装具有优异的T2加权磁共振(MR)成像性能。此外,CPSP释放的CoPP可以通过上调血红素加氧酶1(HO-1)的表达来有效保护MSCs。CPSP的体内细胞示踪能力通过在大脑中动脉闭塞小鼠模型中用MR成像监测标记的MSC的迁移来确认。更重要的是,CPSPs持续释放CoPP可改善移植MSCs的存活,促进缺血小鼠的神经修复和神经行为恢复。总的来说,这项工作提出了一种新颖的双功能纳米剂,其巧妙的设计用于推进基于MSC的治疗。
    Mesenchymal stem cell (MSC)-based therapy has provided a promising strategy for the treatment of ischemic stroke, which is still restricted by the lack of long-term cell tracking strategy as well as the poor survival rate of stem cells in ischemic region. Herein, a dual-functional nanoprobe, cobalt protoporphyrin-induced nano-self-assembly (CPSP), has been developed through a cobalt protoporphyrin IX (CoPP) aggregation-induced self-assembly strategy, which combines CoPP and superparamagnetic iron oxide (SPION) via a simple solvent evaporation-driven method. Without any additional carrier materials, the obtained CPSP is featured with good biocompatibility and high proportions of active ingredients. The SPIONs in CPSPs form a cluster-like structure, endowing this nano-self-assembly with excellent T2-weighted magnetic resonance (MR) imaging performance. Furthermore, the CoPP released from CPSPs could effectively protect MSCs by upregulating heme oxygenase 1 (HO-1) expression. The in vivo cell tracing capacity of CPSPs is confirmed by monitoring the migration of labeled MSCs with MR imaging in a middle cerebral artery occlusion mouse model. More importantly, the sustained release of CoPP from CPSPs improves the survival of transplanted MSCs and promotes neural repair and neurobehavioral recovery of ischemic mice. Overall, this work presents a novel dual-functional nanoagent with an ingenious design for advancing MSC-based therapy.
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  • 文章类型: Journal Article
    磁性光子晶体(PhCs),作为代表性的响应结构颜色材料,由于明亮的折射颜色等优点,吸引了越来越多的研究焦点,即时响应,和优秀的男子气概,因此广泛应用于彩色显示,三维打印,传感,等等。具有非接触式等特征,灵活的方向,和可调节的外部磁力强度,尤其是在生物成像和辅助临床诊断等生物医学应用领域,磁性PhC表现出了极大的优越性。在这次审查中,我们总结了磁性PhC的最新进展。我们首先介绍了PhC的基本原理和典型特征。之后,我们介绍了几种典型的自组装策略及其在实际应用中的前沿。最后,我们分析了磁性PhC的现状,并提出了未来的挑战和未来的发展方向。
    Magnetic photonic crystals (PhCs), as a representative responsive structural color material, have attracted increasing research focus due to merits such as brilliant refraction colors, instant responsiveness, and excellent manipuility, thus having been widely applied for color displaying, three-dimensional printing, sensing, and so on. Featured with traits such as contactless manner, flexible orientations, and adjustable intensity of external magnetism, magnetic PhCs have shown great superiority especially in the field of biomedical applications such as bioimaging and auxiliary clinical diagnosis. In this review, we summarize the current advancements of magnetic PhCs. We first introduce the fundamental principles and typical characteristics of PhCs. Afterward, we present several typical self-assembly strategies with their frontiers in practical applications. Finally, we analyze the current situations of magnetic PhCs and put forward the prospective challenges and future development directions.
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  • 文章类型: Journal Article
    生物分子聚集体确保生化过程发生所需的最佳浓度和接近度。合成聚集系统对于研究/模拟自然界中的动态冷凝物变得越来越重要。本文报道了使用镧系元素盐的自组装DNA构建体的比率DNA聚集。此外,通过添加特定的镧系元素结合配体,可以逆转聚集。通过动态光散射实验证实了聚集体的形成。电泳迁移率变动分析,场发射扫描电子显微镜。这种编程的DNA聚集及其逆转用于评估镧系元素-DNA和镧系元素-配体结合常数,分别。为了实现这一点,福斯特共振能量转移(FRET)对染料在DNA链的3'或5'末端策略性地放置,产生独特的荧光模式与DNA构建体和不同的触发如镧系元素/配体/单价阳离子相互作用,从而能够跟踪绑定的各种状态。它还展示了使用镧系元素形成和稳定G-四链体(GQ)的“快速方法”,该方法补充了Na/K离子对GQs的缓慢形成。镧系元素GQ的形成得到了FRET的证实,圆二色性(CD),和酶联免疫吸附测定(ELISA)实验。这些DNA构建体,由镧系元素形成,显示出对DNA酶I切割的抗性,和独特的结合原卟啉染料和硫磺素T。
    Biomolecular aggregates ensure the optimum concentration and proximity required for biochemical processes to take place. Synthetic aggregating systems are becoming increasingly essential to study/mimic dynamic condensates in nature. Herein the ratiometric DNA aggregation of self-assembled DNA constructs using lanthanide salts is reported. In addition, the aggregation is shown to be reversed by the addition of specific lanthanide-binding ligands. The aggregate formation is confirmed by dynamic light scattering experiment, electrophoretic mobility shift assay, and field emission scanning electron microscope. This programmed DNA aggregation and its reversion are applied to evaluating the lanthanide-DNA and lanthanide-ligand binding constants, respectively. To achieve this, Forster resonance energy transfer (FRET) pair dyes at the 3\' or 5\' end of the DNA strands are strategically placed that generate unique fluorescence patterns upon interaction with the DNA constructs and different triggers such as lanthanides/ligands/monovalent cations, thus enabling the tracking of various states of binding. It also demonstrates a \"fast method\" to form and stabilize G-quadruplex (GQ) using lanthanides which complements the existing slow formation of GQs with Na+/K+ ions. The formation of GQ by lanthanides is corroborated by FRET, circular dichroism (CD), and enzyme linked immunosorbent assay (ELISA) experiments. These DNA constructs, formed by lanthanides, have shown resistance to cleavage by DNase I, and distinctive binding to Protoporphyrin dyes and Thioflavin T.
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  • 文章类型: Journal Article
    目前的溶栓药物由于其有限的循环时间而表现出次优的治疗结果和潜在的出血风险。血栓渗透不足,和脱靶生物分布。在这里,装载了光敏剂,成功开发了红细胞膜封装的多个磁性纳米颗粒聚集体,用于综合机械/光热/光动力溶栓。红细胞膜涂层赋予磁性颗粒延长的血液循环和优越的生物相容性。在预设的旋转磁场(RMF)下,具有不对称磁分布的聚集体开始向血凝块界面滚动运动,由于磁偶极子-偶极子相互作用,聚集体倾向于自组装成更长的,具有强大机械搅拌力的柔性链状微型机器人群,从而促进血栓渗透和机械溶栓。此外,精确的磁控制使目标光敏剂积累,允许近红外(NIR)光有效转化为热和活性氧(ROS)用于血栓光疗。在溶栓试验中,血栓的重量大量减少约90%。这项工作提出了一种更安全,更有前途的磁性微型机器人技术和光疗相结合的多模态溶栓。
    Current thrombolytic drugs exhibit suboptimal therapeutic outcomes and potential bleeding risks due to their limited circulation time, inadequate thrombus penetration, and off-target biodistribution. Herein, a photosensitizer-loaded, red cell membrane-encapsuled multiple magnetic nanoparticles aggregate is successfully developed for integrated mechanical/photothermal/photodynamic thrombolysis. Red cell membrane coating endows magnetic particles with prolonged blood circulation and superior biocompatibility. Under a preset rotating magnetic field (RMF), the aggregate with asymmetric magnetic distribution initiates rolling motion toward the blood clot interface, and because of magnetic dipole-dipole interactions, the aggregate tends to self-assemble into longer, flexible chain-like microrobotic swarm with powerful mechanical stir forces, thereby facilitating thrombus penetration and mechanical thrombolysis. Moreover, precise magnetic control enables targeted photosensitizer accumulation, allowing effective conversion of near-infrared (NIR) light into heat and reactive oxygen species (ROS) for thrombus phototherapy. In thrombolysis assays, the weight of thrombi is massively reduced by ≈90%. The work presents a safer and more promising combination of magnetic microrobotic technology and phototherapy for multi-modality thrombolysis.
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  • 文章类型: Journal Article
    环氧树脂(EP)的阻燃性和导热性能的优化,用于关键应用,如机械部件和电子封装,是一个重大挑战。这项研究介绍了一部小说,超声辅助自组装技术,以创建由碳纳米管和聚磷酸铵(CNT@APP)组成的双功能填料。这种方法,利用动态配体相互作用和战略溶剂选择,允许精确控制碳纳米管在APP表面上的组装和分布,将其与传统的混合方法区分开来。7.5重量的积分。%CNTs@APP10加入EP纳米复合材料可显著提高阻燃性,极限氧指数(LOI)值为31.8%,并达到UL-94V-0等级。此外,关键火灾危险指标,包括总放热(THR),总烟雾释放量(TSR),和CO产量(PCOY)的峰强度,大幅减少45.9%至77.5%。这种方法还导致了显著的3.6倍提高的焦炭产量,展示了其在传统混合技术上改变游戏规则的潜力。此外,尽管添加了最少的碳纳米管,热导率显著增强,增加了53%。这项研究为多功能EP纳米复合材料的开发提供了一种新的方法,提供广泛的应用潜力。
    The optimization of flame retardancy and thermal conductivity in epoxy resin (EP), utilized in critical applications such as mechanical components and electronics packaging, is a significant challenge. This study introduces a novel, ultrasound-assisted self-assembly technique to create a dual-functional filler consisting of carbon nanotubes and ammonium polyphosphate (CNTs@APP). This method, leveraging dynamic ligand interactions and strategic solvent selection, allows for precise control over the assembly and distribution of CNTs on APP surfaces, distinguishing it from conventional blending approaches. The integration of 7.5 wt.% CNTs@APP10 into EP nanocomposites results in substantial improvements in flame retardancy, as evidenced by a limiting oxygen index (LOI) value of 31.8% and achievement of the UL-94 V-0 rating. Additionally, critical fire hazard indicators, including total heat release (THR), total smoke release (TSR), and the peak intensity of CO yield (PCOY), are significantly reduced by 45.9% to 77.5%. This method also leads to a remarkable 3.6-fold increase in char yield, demonstrating its game-changing potential over traditional blending techniques. Moreover, despite minimal CNTs addition, thermal conductivity is notably enhanced, showing a 53% increase. This study introduces a novel approach in the development of multifunctional EP nanocomposites, offering potential for wide range of applications.
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  • 文章类型: Journal Article
    水性纳米粒子的单线态裂变特性,从具有或不具有手性的并四苯二羧酸和各种胺的离子对自组装,被彻底调查。铵分子的结构,反离子,被发现在确定离子对的分子取向及其规律性中起决定性作用,光谱特性,并四苯发色团之间的分子间偶联强度,以及随之而来的单线态裂变过程。使用手性胺导致晶体纳米片的形成和有效的单线态裂变,三重态量子产率高达133%±20%,速率常数为6.99×109s-1。手性离子对还为游离三重态提供分离通道,产率高达33%±10%。相比之下,具有非手性抗衡离子的纳米粒子不显示单线态裂变,这给出了低或高荧光量子产率取决于抗衡离子的大小。外消旋离子对通过单线态裂变产生相关的三重态对中间体,但是没有观察到两个自由三胞胎的去相关,正如三重态-三重态湮灭占主导地位。手性的引入使得能够对自组装发色团中的取向和单线态裂变进行更高的控制。它为单线态裂变材料提供了新的设计准则。
    The singlet fission characteristics of aqueous nanoparticles, self-assembled from ion pairs of tetracene dicarboxylic acid and various amines with or without chirality, are thoroughly investigated. The structure of the ammonium molecule, the counterion, is found to play a decisive role in determining the molecular orientation of the ion pairs and its regularity, spectroscopic properties, the strength of the intermolecular coupling between the tetracene chromophores, and the consequent singlet fission process. Using chiral amines has led to the formation of crystalline nanosheets and efficient singlet fission with a triplet quantum yield as high as 133% ±20% and a rate constant of 6.99 × 109 s-1. The chiral ion pairs also provide a separation channel to free triplets with yields as high as 33% ±10%. In contrast, nanoparticles with achiral counterions do not show singlet fission, which gave low or high fluorescence quantum yields depending on the size of the counterions. The racemic ion pair produces a correlated triplet pair intermediate by singlet fission, but no decorrelation into two free triplets is observed, as triplet-triplet annihilation dominates. The introduction of chirality enables higher control over orientation and singlet fission in self-assembled chromophores. It provides new design guidelines for singlet fission materials.
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  • 文章类型: Journal Article
    环状纳米结构是惊人的材料,显示独特的光学,磁性,和电子性质与它们的尺寸高度相关。能够连续调整纳米环直径的策略是阐明其结构-功能关系的关键。在这里,建立了一种由疏水性诱导的双组分胶束构型转化方法,用于合成直径从亚微米(约143nm)到微米(约4.8µm)的纳米环及其碳质类似物。值得注意的是,用这种液相策略制造的纳米环达到了最大直径跨度的记录。通过改变脂肪醇和共聚物的分子长度,缩短脂肪醇的分子长度可以使初级胶束膨胀,这里显示了改善疏水性组分的暴露并增强了超大型纳米环的组装动力学。另一方面,缩短共聚物的分子长度将通过减小初级胶束的尺寸和缩短组装时间而产生超小的纳米环。当将纳米环组装成单层阵列然后沉积Au时,这样的基底显示增强的表面增强拉曼散射(SERS)性能。这项研究开发了一种简单的方法,用于可控合成具有多尺度可调直径的环状材料,并可能激发物理学中更有趣的应用。光学,和传感器。
    Ringy nanostructures are amazing materials, displaying unique optical, magnetic, and electronic properties highly related to their dimensions. A strategy capable of continuously tailoring the diameter of nanorings is the key to elucidating their structure-function relationship. Herein, a method of bi-component micellar-configuration-transformation induced by hydrophobicity for the synthesis of nanorings with diameters ranging from submicron (≈143 nm) to micron (≈4.8 µm) and their carbonaceous analogs is established. Remarkably, the nanorings fabricated with this liquid phase strategy achieve the record for the largest diameter span. Through varying the molecular lengths of fatty alcohols and copolymers, shortening the molecular length of fatty alcohol can swell the primary micelles, improve the exposure of hydrophobic component and boost the assembly kinetics for ultra-large nanorings is shown here. On the other hand, shortening the molecular length of the copolymer will give rise to ultra-small nanorings by reducing the size of primary micelles and shortening the assembly time. When assembling the nanorings into monolayer arrays and then depositing Au, such substrate displays enhanced surface-enhanced Raman scattering (SERS) performance. This research develops a facile method for the controllable synthesis of ringy materials with multiscale tunable diameters and may inspire more interesting applications in physics, optical, and sensors.
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