Molecular encapsulation

  • 文章类型: Journal Article
    风味被认为是影响食品质量的最重要因素之一。然而,它通常容易受到环境因素的影响,因此,封装对于促进适当的处理和加工是非常必要的。在这项研究中,研究了淀粉包封的结构变化及其对风味保持性的影响,使用in淀粉(RS)作为基质来包封三种风味化合物,即壬酸,1-辛醇,和2-戊基呋喃。流变学和质构结果表明,包含风味化合物改善了淀粉分子之间的分子间相互作用,导致淀粉凝胶的物理化学性质显著增加,顺序为:壬酸>1-辛醇>2-戊基呋喃。XRD结果证实了v-淀粉的成功制备。此外,用FT-IR对包合物(IC)进行了表征,SEM,和DSC技术。结果表明,v-淀粉与风味分子形成复合物。配合物的较高焓表明醇和酸的添加可以改善淀粉分子之间的分子间络合。利用HS-GC测定了三种风味化合物在淀粉中的保留率。值为51.7%,32.37%,35.62%。总的来说,这项研究提供了对提高质量和风味保留的新方法的见解,提高储存性和稳定性,减少加工和储存过程中的损失,并延长淀粉产品的保质期。
    Flavor is considered one of the most significant factors affecting food quality. However, it is often susceptible to environmental factors, so encapsulation is highly necessary to facilitate proper handling and processing. In this study, the structural changes in starch encapsulation and their effects on flavor retention were investigated using indica starch (RS) as a matrix to encapsulate three flavoring compounds, namely nonanoic acid, 1-octanol, and 2-pentylfuran. The rheological and textural results suggested that the inclusion of flavor compounds improved the intermolecular interactions between starch molecules, resulting in a significant increase in the physicochemical properties of starch gels in the order: nonanoic acid > 1-octanol > 2-pentylfuran. The XRD results confirmed the successful preparation of v-starch. Additionally, the inclusion complexes (ICs) were characterized using FT-IR, SEM, and DSC techniques. The results showed that v-starch formed complexes with Flavor molecules. The higher enthalpy of the complexes suggested that the addition of alcohols and acids could improve the intermolecular complexation between starch molecules. The retention rates of three flavor compounds in starch were determined using HS-GC, with the values of 51.7 %, 32.37 %, and 35.62 %. Overall, this study provides insights into novel approaches to enhance the quality and flavor retention, improve the storability and stability, reduce losses during processing and storage, and extend the shelf life of starchy products.
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  • 文章类型: Journal Article
    胶体颗粒在钙钛矿前体中的不均匀分布导致在柔性印刷过程中对剪切力的不平衡响应。在这里,我们观察到,钙钛矿油墨中发生的连续无序迁移显着促进了胶体颗粒尺寸的增大,并降低了油墨的结晶活性。因此,我们设计了一种通过单硬脂酸甘油酯(GMS)的分子封装结构,以减轻前体墨水中的胶体颗粒碰撞,同时使钙钛矿胶体的尺寸分布均匀化,以最大程度地减少其扩散差异。利用具有分子封装结构的胶体颗粒,可以在印刷过程中实现均匀沉积,从而有效地平衡膜中的结晶速率和相变并促进钙钛矿膜的均匀结晶。通过印刷工艺制造的大面积柔性钙钛矿器件(1.01cm2和100cm2),实现了24.45%和15.87%的效率,分别,并表现出优越的环境稳定性,在大气环境中储存150天后(未封装)保持91%的初始效率。这项工作表明,前体油墨和印刷过程中胶体颗粒的动力学演化过程代表了实现钙钛矿膜均匀结晶的关键一步。本文受版权保护。保留所有权利。
    The non-uniform distribution of colloidal particles in perovskite precursor results in an imbalanced response to the shear force during flexible printing process. Herein, it is observed that the continuous disordered migration occurring in perovskite inks significantly contributes to the enlargement of colloidal particles size and diminishes the crystallization activity of the inks. Therefore, a molecular encapsulation architecture by glycerol monostearate to mitigate colloidal particles collisions in the precursor ink, while simultaneously homogenizing the size distribution of perovskite colloids to minimize their diffusion disparities, is devised. The utilization of colloidal particles with a molecular encapsulation structure enables the achievement of uniform deposition during the printing process, thereby effectively balancing the crystallization rate and phase transition in the film and facilitating homogeneous crystallization of perovskite films. The large-area flexible perovskite device (1.01 cm2 and 100 cm2) fabricated through printing processes, achieves an efficiency of 24.45% and 15.87%, respectively, and manifests superior environmental stability, maintaining an initial efficiency of 91% after being stored in atmospheric ambiences for 150 days (unencapsulated). This work demonstrates that the dynamic evolution process of colloidal particles in both the precursor ink and printing process represents a crucial stride toward achieving uniform crystallization of perovskite films.
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  • 文章类型: Journal Article
    发光稳定性是决定镧系元素发光材料应用的重要因素。设计形成具有可预测的连接模式的扩展框架的发光镧系元素团簇节点可以帮助增强镧系元素络合物的结构稳定性,并因此导致改善的发光稳定性。在这里,我们报道了一系列一维(1D)稀土金属-有机骨架化合物,{Ln4(μ4-OH)(TC4A)2(H2O)2(CH3O)(HCOO)2(HCOOH)}·xCH3OH(Ln=Sm(1),Eu(2),TB(3),Dy(4);x=1-5),基于双硫柳[4]芳烃封端的Ln4(μ4-OH)(TC4A)2节点。轴向加盖的Ln4(μ4-OH)(TC4A)2节点通过甲酸桥等向连接,形成锯齿形1D金属有机骨架(MOF)链,通过氢键进一步组装成准二维(2D)结构。这些独特的特征导致稳定的结构和因此优异的发光稳定性。例如,基于Tb的1D-MOF(3)表现出强烈的绿色光致发光,量子产率为53%,平均衰减时间为1.33×106ns。在暴露于水分(在水中浸泡10天)后,其综合发射强度保持在原始值的96.5、94.5和89.4%,高温(150°C),和紫外线(连续辐射15天),分别,表现出优异的发光稳定性。我们采用基于Tb的1D-MOF(3)作为绿色荧光粉,并成功地制造了原型白色发光二极管(LED),在长期运行下具有稳定的发射性能。我们的合成策略允许控制镧系元素节点的连接模式,提供了获得具有改善的发光稳定性的镧系元素MOFs的预测途径。
    Luminescent stability is a vital factor that dictates the application of lanthanide luminescent materials. Designing luminescent lanthanide cluster nodes that form an extended framework with predictable linking patterns may help enhance the structural stability of the lanthanide complexes and hence lead to improved luminescent stability. Herein, we report a series of one-dimensional (1D) rare-earth metal-organic framework compounds, {Ln4(μ4-OH)(TC4A)2(H2O)2(CH3O)(HCOO)2(HCOOH)}·xCH3OH (Ln = Sm (1), Eu (2), Tb (3), Dy (4); x = 1-5), based on double thiacalix[4]arene-capped Ln4(μ4-OH)(TC4A)2 nodes. The axially capped Ln4(μ4-OH)(TC4A)2 nodes are connected equatorially by formate bridges to form zigzag 1D-metal-organic framework (MOF) chains, which further assemble into a quasi-two-dimensional (2D) structure via hydrogen bonding. These unique features result in a stable structure and therefore superior luminescent stability. For example, the Tb-based 1D-MOF (3) exhibits intensive green photoluminescence with a quantum yield of 53% and an average decay time of 1.33 × 106 ns. It maintains its integrated emission intensity at 96.5, 94.5, and 89.4% of the original value after being exposed to moisture (soaking in water for 10 days), elevated temperature (150 °C), and UV (15 days of continuous radiation), respectively, demonstrating excellent luminescent stability. We adopt the Tb-based 1D-MOF (3) as the green phosphor and successfully fabricate a prototype white-light-emitting diode (LED) with stable emission under long-term operation. Our synthetic strategy allows control over the linking pattern of lanthanide nodes, providing a predictive route to obtain lanthanide MOFs with improved luminescent stability.
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  • 文章类型: Journal Article
    通过结合大规模耗散粒子动力学和转向分子动力学模拟,我们研究了均相和非均相纳米水凝胶的机械化学细胞内化途径,并证明了膜内化是由纳米水凝胶的交联密度和包封能力决定的。具有高交联密度和低包封能力的均质纳米水凝胶表现为部分被膜包裹的软纳米颗粒。而那些具有低交联密度和高封装能力的渗透进入膜。无论交联密度如何,均匀的纳米水凝胶经历典型的双重形态变形。由于内化过程中脂质和受体分子之间的扩散行为不同,因此在膜和纳米水凝胶之间的接触区域鉴定了局部脂质纳米结构域。蛋黄@壳异质纳米水凝胶呈现不同的机械化学细胞内化途径。亲和力强的蛋黄直接与膜接触,导致部分膜包裹,与均质纳米水凝胶相比,接触面积大大减少,导致更小的脂质纳米结构域,从而避免相关的细胞毒性。我们的发现为纳米水凝胶的生物学途径提供了关键的机制理解,并可能指导用于控释药物递送的基于水凝胶的材料的分子设计。组织工程,和细胞培养。
    By combining large-scale dissipative particle dynamics and steered molecular dynamics simulations, we investigate the mechanochemical cellular internalization pathways of homogeneous and heterogeneous nanohydrogels and demonstrate that membrane internalization is determined by the crosslink density and encapsulation ability of nanohydrogels. The homogeneous nanohydrogels with a high crosslink density and low encapsulation ability behave as soft nanoparticles partially wrapped by the membrane, while those with a low crosslink density and high encapsulation ability permeate into the membrane. Regardless of the crosslink density, the homogeneous nanohydrogels undergo typical dual morphological deformations. The local lipid nanodomains are identified at the contacting region between the membrane and nanohydrogels because of different diffusion behaviors between lipid and receptor molecules during the internalization process. The yolk@shell heterogeneous nanohydrogels present a different mechanochemical cellular internalization pathway. The yolk with strong affinity is directly in contact with the membrane, resulting in partial membrane wrapping, and the contacting area is much reduced when compared to homogenous nanohydrogels, leading to a smaller lipid nanodomain and thus avoiding related cellular toxicity. Our findings provide a critical mechanism understanding of the biological pathways of nanohydrogels and may guide the molecular design of the hydrogel-based materials for controlled release drug delivery, tissue engineering, and cell culture.
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  • 文章类型: Journal Article
    Large unilamellar vesicles [1]n , composed of bolaamphiphilic baskets 1, were found to complex photoresponsive guest 3 and divalent 4 to, respectively, give stable vesicular assemblies [12 -3]n and [12 -43 ]n . With the assistance of 1 H NMR spectroscopy, electron microscopy, and dynamic light scattering, it was deduced that [12 -3]n vesicles comprise ternary [12 -3] organized into a curved membrane in which a pair of baskets entraps a laterally positioned dicationic 3. In the case of [12 -43 ]n vesicles, however, the spectroscopic results suggest that three guest molecules 4 insert vertically between four baskets 1 to give pentanary [12 -43 ] packed into the membrane of [12 -43 ]n . Importantly, nanostructured [12 -3]n and [12 -43 ]n retain rhodamine B (RhB) in their reservoir (fluorescence microscopy) and can be switched from one into another using UV light, with a disproportionate release of RhB dye. The reported complexes, organized into photoresponsive capsular materials, are rather unprecedented, demonstrating the potential of multivalency for creating functional structures of great interest in the areas of catalysis and delivery.
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  • 文章类型: Journal Article
    The complete structure of non-crystalline compounds can be determined by confining them in crystalline structures. The reduced motional degrees of freedom of encapsulated guests can be obtained through their anchoring to the host cages, which results in the reduction of a significant amount of disorder. The \"pyrene box\" cages that easily crystallize from aqueous solutions are recommended to achieve complete structure elucidation of compounds of biological interest. In this study, the \"pyrene box\" cages have been used for the in situ encapsulation of biogenic amines: histamine, dopamine, and serotonin. NMR spectroscopy illustrates that these systems are stable in aqueous solution. The X-ray single-crystal structure analysis reveals that the pyrene box/biogenic amine systems are stabilized through combined interactions, strongly contributing to in situ fixation and accurate determination of their crystal structures.
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