Hydrophobic and Hydrophilic Interactions

疏水和亲水相互作用
  • 文章类型: Journal Article
    糖基化和磷酸化是最重要的翻译后修饰,他们的分析在很大程度上依赖于富集技术。在这项工作中,开发了一种简便的方法,用于一步同时富集和逐步洗脱糖蛋白和磷蛋白。这种方法的核心是用树枝状聚合物聚乙烯亚胺和植酸官能化的新型钛(IV)离子固定的聚(甲基丙烯酸缩水甘油酯)微粒的应用。由于其表面上丰富的钛离子和羟基,微粒具有双重富集能力。它们表现出快速吸附平衡(在30分钟内)和对β-酪蛋白(1107.7mg/g)和辣根过氧化物酶(438.6mg/g)的特殊吸附能力,超过牛血清白蛋白(91.7mg/g)。此外,进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳以验证富集能力。各种生物样本的实验结果,包括标准的蛋白质混合物,脱脂牛奶,和人类血清,证明了这些微粒从生物样品中富集低丰度糖蛋白和磷蛋白的显着能力。
    Glycosylation and phosphorylation rank as paramount post-translational modifications, and their analysis heavily relies on enrichment techniques. In this work, a facile approach was developed for the one-step simultaneous enrichment and stepwise elution of glycoproteins and phosphoproteins. The core of this approach was the application of the novel titanium (IV) ion immobilized poly(glycidyl methacrylate) microparticles functionalized with dendrimer polyethylenimine and phytic acid. The microparticles possessed dual enrichment capabilities due to their abundant titanium ions and hydroxyl groups on the surface. They demonstrate rapid adsorption equilibrium (within 30 min) and exceptional adsorption capacity for β-casein (1107.7 mg/g) and horseradish peroxidase (438.6 mg/g), surpassing that of bovine serum albumin (91.7 mg/g). Furthermore, sodium dodecyl sulfate-polyacrylamide gel electrophoresis was conducted to validate the enrichment capability. Experimental results across various biological samples, including standard protein mixtures, non-fat milk, and human serum, demonstrated the remarkable ability of these microparticles to enrich low-abundance glycoproteins and phosphoproteins from biological samples.
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  • 文章类型: Journal Article
    2,3-顺式没食子酸酯型儿茶素(-)-表没食子儿茶素-3-O-没食子酸酯(EGCg)和咖啡因的水溶液提供了乳油沉淀现象,缓慢结晶约三个月,得到无色块状晶体。通过X射线晶体学分析,晶体被确定为EGCg和咖啡因的2:2复合物,其中咖啡因分子被捕获在由三个芳香族A形成的疏水空间中,B,和B\'EGCg环。认为2:2络合物在水中的溶解度迅速降低,并且2:2络合物从水溶液中沉淀。EGCg的疏水空间捕获了多种杂环化合物,并使用EGCg从水溶液中评估了杂环化合物的分子捕获能力。由于EGCg的C环有两个手性碳原子,C2和C3,EGCg的疏水空间为手性空间。EGCg捕获的环二酮哌嗪(Pro-Xxx)(Xxx=Phe,Tyr)和带有黄嘌呤骨架的药物,proxyphyline和didiprepetroline,在疏水空间中,并认识到他们的手性。
    An aqueous solution of 2,3-cis gallate type catechin (-)-epigallocatechin-3-O-gallate (EGCg) and caffeine afforded a precipitate of Creaming-down Phenomenon, which crystallized slowly for about three months to give a colorless block crystal. By X-ray crystallographic analysis, the crystal was determined to be a 2 : 2 complex of EGCg and caffeine, in which caffeine molecules were captured in a hydrophobic space formed with three aromatic A, B, and B\' rings of EGCg. It was considered that the solubility of the 2 : 2 complex in water rapidly decreased and the 2 : 2 complex precipitated from aqueous solution. The hydrophobic spaces of EGCg captured a variety of heterocyclic compounds, and the molecular capture abilities of heterocyclic compounds using EGCg from the aqueous solutions were evaluated. Since the C ring of EGCg has two chiral carbon atoms, C2 and C3, the hydrophobic space of EGCg was a chiral space. EGCg captured diketopiperazine cyclo(Pro-Xxx) (Xxx=Phe, Tyr) and pharmaceuticals with a xanthine skeleton, proxyphylline and diprophylline, in the hydrophobic space, and recognized their chirality.
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  • 文章类型: Journal Article
    通过物理挤压形成了从鱼碎中重组肉基产品的多层结构,然后研究了油炸前后挤出强度对结构和理化性能的影响。在适当的压力(3-9kPa)下,鱼碎中的空气经过富集和重新排列,形成一个分层阶段,促进油炸过程中多层结构的形成。相反,较低的压力(≤1.5kPa)不足以进行相分离和定向重排,而较高的压力(≥15kPa)会导致分层阶段流出食物系统。此外,通过直接增加水的流动性和肉的紧密度,物理挤压间接导致油炸过程中更多的失水和更强的离子键,与多层结构呈正相关。然而,过高的压力导致油炸过程中无规卷曲和疏水相互作用的增加,与多层结构呈负相关。总之,适当的物理挤压强度促进了多层结构的形成。
    Multi-layered structure of reconstituted meat-based products from minced fish was formed by physical extrusion, followed by an investigation into the impact of extrusion strength on structural and physicochemical properties before and after frying. Under an appropriate pressure (3-9 kPa), the air within minced fish underwent enrichment and rearrangement to form a stratified phase, promoting the formation of multi-layered structure during frying. Conversely, the lower pressure (≤1.5 kPa) was insufficient for phase separation and directional rearrangement, while the higher pressure (≥15 kPa) would cause the stratified phase to flow out of food system. Moreover, by directly increasing water mobility and meat compactness, physical extrusion indirectly caused more water loss and stronger ionic bonds during frying, which was positively correlated with multi-layered structure. However, an excessive pressure caused an increase in random coil and hydrophobic interactions during frying, which was negatively correlated with multi-layered structure. In conclusion, appropriate physical extrusion strength promoted the formation of multi-layered structure.
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  • 文章类型: Journal Article
    在乳制品中,添加的透明质酸钠可以与蛋白质形成复合物,从而影响产品性能。在本研究中,在不同温度(25℃,65℃,90℃和121℃)研究了蛋白质/SH比和pH对复合物形成的影响。SH的添加降低了WPI/WPH的粒径,增加了系统中的电位值,随着处理温度的升高而变化较大。研究了配合物的结构性质。与SH的结合降低了游离氨基和游离巯基的含量,以及荧光强度和表面疏水性。FTIR结果和褐变强度测量证明了美拉德反应产物的形成。此外,SH的附着提高了WPI/WPH的热稳定性,降低了其抗原性。
    In dairy products, the added sodium hyaluronate may form complexes with proteins, thereby affecting product properties. In the present study, the interaction between whey protein isolate (WPI)/ whey protein hydrolysate (WPH) and sodium hyaluronate (SH) was characterized under thermal treatment at different temperatures (25 ℃, 65 ℃, 90 ℃ and 121 ℃) after studying effects of protein/SH ratio and pH on complex formation. The addition of SH reduced the particle size of WPI/WPH and increased potential value in the system, with greater variation with increasing treatment temperature. The structural properties of complexes were studied. The binding with SH decreased the contents of free amino group and free thiol group, as well as the fluorescence intensity and surface hydrophobicity. FTIR results and browning intensity measurement demonstrated the formation of Maillard reaction products. Moreover, the attachment of SH improved the thermal stability of WPI/WPH and decreased their antigenicity.
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  • 文章类型: Journal Article
    研究了使用碱性和自由基介导的方法(AM和FRM)结合超声处理合成的乳清-槲皮素和乳清水解物-槲皮素缀合物的结构和功能特性。FTIR显示在3000-3500cm-1(N-H拉伸区域)和具有缀合物的1000-1100cm-1区域的新峰。共轭增加了无规卷曲和α-螺旋含量,同时减少了β-折叠和转弯。它还增加了颗粒尺寸和表面疏水性,其在AM中显著高于(p<0.05)FRM缀合物。与FRM缀合物相比,AM缀合物具有更高的自由基清除活性,但槲皮素含量较低。总的来说,乳清-槲皮素偶联物的功能特性优于乳清水解物-槲皮素偶联物。然而,无论生产方法如何,水解产物缀合物具有显著更高的变性温度。超声处理提高了FRM缀合物的自由基清除活性和槲皮素含量,而AM缀合物的两者均降低。该研究表明,乳清-槲皮素缀合物通常具有比乳清水解物缀合物更好的质量,并且超声处理倾向于进一步改善这些性质。这项研究强调了使用骆驼乳清或乳清水解物-槲皮素结合物来增强食品工业中食品的功能特性的潜力。
    The structural and functional properties of whey-quercetin and whey hydrolysate-quercetin conjugates synthesized using alkaline and free radical-mediated methods (AM and FRM) coupled with sonication were studied. FTIR showed new peaks at 3000-3500 cm-1 (N-H stretching regions) and the 1000-1100 cm-1 region with the conjugates. Conjugation increased the random coils and α-helix content while decreasing the β-sheets and turns. It also increased the particle size and surface hydrophobicity which was significantly (p < 0.05) higher in AM than FRM conjugates. AM conjugates had higher radical scavenging activity but lower quercetin content than FRM conjugates. Overall, the functional properties of whey-quercetin conjugates were better than whey hydrolysate-quercetin conjugates. However, hydrolysate conjugates had significantly higher denaturation temperatures irrespective of the method of production. Sonication improved the radical scavenging activity and quercetin content of FRM conjugates while it decreased both for AM conjugates. This study suggested that whey-quercetin conjugates generally had better quality than whey hydrolysate conjugates and sonication tended to further improve these properties. This study highlights the potential for using camel whey or whey hydrolysate-quercetin conjugates to enhance the functional properties of food products in the food industry.
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  • 文章类型: Journal Article
    在亲水相互作用液相色谱(HILIC)条件下研究了所选化合物的色谱行为。使用高效薄层色谱法系统地检查了流动相组成对不同色谱系统中保留率的影响。选择了不同极性和吸附特性的吸附剂,并将水和各种组成的有机溶剂混合,从纯水到纯有机溶剂用作流动相。增加流动相中的水量导致分离机制的转变,并且保留曲线具有特征“U”形。吸附和分配机制之间的转换很可能是连续的,并且取决于分离物质的化学性质,固定相以及流动相的有机组分。硅胶可以被认为是对测试化合物的色谱行为进行系统研究的最合适的固定相,而乙腈是最合适的溶剂。获得的结果有助于理解主导分离机制,类型,以及分离物质与固定相和流动相之间的相互作用强度。此外,评估了在HILIC条件下获得的亲脂性参数,并将其与计算值相关联。
    The chromatographic behavior of the selected compounds was studied under conditions of hydrophilic interaction liquid chromatography (HILIC). The effect of mobile phase composition on the retention in different chromatographic systems was systematically examined using high-performance thin-layer chromatography. The sorbents of different polarity and adsorption characteristics were selected and mixtures of water and organic solvents of various compositions, from pure water to pure organic solvent were used as mobile phases. Increasing the amount of water in the mobile phase leads to a conversion of the separation mechanism, and the retention curves have a characteristic \"U\" shape. The conversion between the adsorption and partition mechanisms is most likely continuous and depends on the chemical nature of separated substances, the stationary phase as well as on organic component of the mobile phase. Silica gel can be considered the most suitable stationary phase for the systematic investigation of the chromatographic behavior of the test compounds, whereas acetonitrile was the most suitable solvent. The obtained results contribute to the understanding of the dominant separation mechanism, the type, and the intensity of the interactions between separated substances with both stationary and mobile phases. Besides, the lipophilicity parameters obtained under HILIC conditions were evaluated and correlated with the calculated values.
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  • 文章类型: Journal Article
    已经检查了各种IgG抗体的Fc碱基的结构,以了解该区域如何可用于将IgG缀合至纳米颗粒。发现基本结构在一系列物种和亚型中基本一致,包含由亲水残基包围的疏水区,其中一些是在生理条件下充电的。此外,进行了原子分子动力学模拟,以探索模型纳米粒子如何使用中性和带负电荷的金纳米粒子与碱相互作用。两种类型的纳米粒子都容易与碱相互作用,导致抗体基础表面的适应以增强相互作用。此外,这些相互作用使结构域的其余部分在Fc区的底部在结构上完整。这意味着将纳米颗粒与IgG分子的碱基偶联是可行的和合乎需要的。因为它使抗体自由地与其周围环境相互作用,从而可以保留抗原结合功能。因此,这些结果将有助于指导未来开发新的纳米技术,利用抗体和纳米颗粒的独特特性。
    The structures of the Fc base of various IgG antibodies have been examined with a view to understanding how this region can be used to conjugate IgG to nanoparticles. The base structure is found to be largely consistent across a range of species and subtypes, comprising a hydrophobic region surrounded by hydrophilic residues, some of which are charged at physiological conditions. In addition, atomistic Molecular Dynamics simulations were performed to explore how model nanoparticles interact with the base using neutral and negatively charged gold nanoparticles. Both types of nanoparticle interacted readily with the base, leading to an adaptation of the antibody base surface to enhance the interactions. Furthermore, these interactions left the rest of the domain at the base of the Fc region structurally intact. This implies that coupling nanoparticles to the base of an IgG molecule is both feasible and desirable, since it leaves the antibody free to interact with its surroundings so that antigen-binding functionality can be retained. These results will therefore help guide future attempts to develop new nanotechnologies that exploit the unique properties of both antibodies and nanoparticles.
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  • 文章类型: Journal Article
    我们的研究旨在探索使用纳米结构脂质载体(NLCs)来增强β-谷甾醇的局部给药的潜力,难溶于水的生物活性物质。这里,我们利用了立方体作为药物递送系统所具有的独特特性。这些特征包括大的表面积,热稳定性,以及封装疏水分子的能力,两亲性,和亲水性。通过构建中心复合材料设计来优化立方体制剂。最佳分散体的粒径为88.3nm,zeta电位为-43,多分散指数为0.358,药物包封率为95.6%。它由15%w/w的油酸和5%w/w的pluronicF127组成。将优化的立方体分散体掺入海绵制剂中。与长方体分散体相比,优化的长方体海绵实现了更高的药物释放。所选海绵的SEM显微照片表明,它具有低密度和高孔隙率的交织不规则纤维层状结构。体内数据显示,相对于β-谷甾醇产品(Mebo)®,局部施用β-谷甾醇立方体海绵显示出显著更高的伤口闭合百分比。
    Our study aimed to explore the potential of using nanostructured lipid carriers (NLCs) to enhance the topical administration of β-sitosterol, a bioactive that is poorly soluble in water. Here, we have taken advantage of the unique characteristics that cubosomes have to provide as a drug delivery system. These characteristics include a large surface area, thermal stability, and the capacity to encapsulate molecules that are hydrophobic, amphiphilic, and hydrophilic. The cubosomal formulation was optimized by building a central composite design. The optimum dispersion exhibited a particle size of 88.3 nm, a zeta potential of -43, a polydispersity index of 0.358, and drug entrapment of 95.6%. It was composed of 15% w/w oleic acid and 5% w/w pluronic F127. The optimized cubosome dispersion was incorporated into a sponge formulation. The optimized cubosome sponge achieved a higher drug release compared with the cubosome dispersion. The SEM micrograph of the selected sponge showed that it has an interwoven irregular fibrous lamellar structure with low density and high porosity. The in-vivo data revealed that topical application of the β-sitosterol cubosomal sponge showed significant higher wound closure percentage relative to the β-sitosterol product (Mebo)®.
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  • 文章类型: English Abstract
    The surface morphology of titanium metal is an important factor affecting its hydrophilicity and biocompatibility, and exploring the surface treatment strategy of titanium metal is an important way to improve its biocompatibility . In this study , titanium (TA4) was firstly treated by large particle sand blasting and acid etching (SLA) technology, and then the obtained SLA-TA4 was treated by single surface treatments such as alkali-heat, ultraviolet light and plasma bombardment. According to the experimental results, alkali-heat treatment is the best treatment method to improve and maintain surface hydrophilicity of titanium. Then, the nanowire network morphology of titanium surface and its biological property, formed by further surface treatments on the basis of alkali-heat treatment, were investigated. Through the cell adhesion experiment of mouse embryonic osteoblast cells (MC3T3-E1), the ability of titanium material to support cell adhesion and cell spreading was investigated after different surface treatments. The mechanism of biological activity difference of titanium surface formed by different surface treatments was investigated according to the contact angle, pit depth and roughness of the titanium sheet surface. The results showed that the SLA-TA4 titanium sheet after a treatment of alkali heat for 10 h and ultraviolet irradiation for 1 h has the best biological activity and stability. From the perspective of improving surface bioactivity of medical devices, this study has important reference value for relevant researches on surface treatment of titanium implantable medical devices.
    钛金属的表面形貌是影响其亲水性及生物相容性的重要因素,探究钛金属表面处理策略是提高其生物相容性的重要途径。本文先采用大颗粒喷砂酸蚀技术(SLA)处理钛金属A4(TA4),对得到的SLA-TA4进行碱热、紫外光照及等离子体轰击等单一方式表面处理。根据实验结果得出,碱热处理是提高并保持钛金属SLA-TA4亲水性的最佳单一处理方法。随后,在碱热处理的基础上,继续研究多种表面处理方式形成的钛金属表面纳米线网络结构及其生物性能。通过小鼠胚胎成骨前体细胞MC3T3-E1黏附实验,比较了不同方式表面处理后,钛金属材料支持细胞黏附、细胞铺展的能力,并根据不同表面处理方式形成的材料表面接触角、微坑深度及粗糙度等参数,分析探讨多种表面处理方式造成的生物活性差异的机制。结果表明,经碱热处理10 h及紫外照射1 h处理后的SLA-TA4 表现出最佳的生物活性及稳定性。从提高医疗器械表面生物活性的角度考虑,本文研究结果或对钛金属植入性器械的表面处理相关研究提供有价值的参考。.
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  • 文章类型: Journal Article
    通过水热合成开发了ZnO纳米棒无纺布(ZNRN),以促进预防呼吸道病原体的传播。通过响应面法提高了ZNRN的超疏水性和抗菌性能。合成的材料表现出显著的防水性,水接触角为163.9°,因此对大肠杆菌的抗菌率为91.8%(E.大肠杆菌)和79.75%的金黄色葡萄球菌(S.金黄色葡萄球菌)。这表明具有较薄肽聚糖的大肠杆菌可能比金黄色葡萄球菌更容易被杀死。这项研究确定了合成条件对抗菌效果的显着影响,全面的多变量分析阐明了潜在的相关性。此外,通过SEM和XRD分析对ZNRN的ZnO纳米棒结构进行了表征。它赋予超疏水性(从而防止细菌粘附到ZNRN表面)和抗菌能力(从而通过刺穿这些纳米棒破坏细胞)的性质。因此,希望将两个这样的特征对齐,以帮助支持个人防护设备的开发,这有助于避免呼吸道感染的传播。
    ZnO nanorod nonwoven fabrics (ZNRN) were developed through hydrothermal synthesis to facilitate the prevention of the transmission of respiratory pathogens. The superhydrophobicity and antibacterial properties of ZNRN were improved through the response surface methodology. The synthesized material exhibited significant water repellency, indicated by a water contact angle of 163.9°, and thus demonstrated antibacterial rates of 91.8% for Escherichia coli (E. coli) and 79.75% for Staphylococcus aureus (S. aureus). This indicated that E. coli with thinner peptidoglycan may be more easily killed than S. aureus. This study identified significant effects of synthesis conditions on the antibacterial effectiveness, with comprehensive multivariate analyses elucidating the underlying correlations. In addition, the ZnO nanorod structure of ZNRN was characterized through SEM and XRD analyses. It endows the properties of superhydrophobicity (thus preventing bacteria from adhering to the ZNRN surface) and antibacterial capacity (thus damaging cells through the puncturing of these nanorods). Consequently, the alignment of two such features is desired to help support the development of personal protective equipment, which assists in avoiding the spread of respiratory infections.
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