functionalization

Functionalization
  • 文章类型: Journal Article
    在环境污染和资源枯竭的情况下,开发和利用生物质资源作为石油的替代品是一个突出的研究重点。在环境保护和可持续发展的推动下,从石油基聚氨酯向生物基聚氨酯的转变是聚氨酯材料发展的主流趋势。生物质来源,如植物油,多糖,木质素在生物基聚氨酯生产中具有广泛的应用前景。这些聚氨酯的功能改性可以进一步扩大其应用范围。本文探讨了各种生物基聚氨酯的制备,它们在不同领域的应用,以及它们预期的未来发展和用途。
    Amid environmental pollution and resource depletion, developing and utilizing biomass resources as alternatives to petroleum is a prominent research focus. Driven by environmental protection and sustainable development, the shift from petroleum-based to bio-based polyurethane is a prevailing trend in polyurethane material development. Biomass sources such as vegetable oil, polysaccharides, and lignin offer extensive application prospects in bio-based polyurethane production. Functional modifications of these polyurethanes can further expand their application range. This article explores the preparation of various bio-based polyurethanes, their applications across different fields, and their anticipated future development and uses.
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  • 文章类型: Journal Article
    具有其模块特性(氨基硫脲+羰基化合物)的硫代氨基脲(TSC)允许在主要R1R2C=N(1)-NH-C(S)-N(4)R3R4核心上最多四个取代基的广泛变化,因此是形成缀合物或纳米颗粒(NP)官能化的有趣工具。在这项工作中,引入二-2-吡啶基酮以配位金属和9-蒽醛以作为R1和R2发光至TSC。改变R3和R4取代基以形成缀合物。在N4位置引入氨基酸以产生[R1R2TSC-间隔区-氨基酸]缀合物。Further,官能团,例如膦酸(R-P(O)(OH)2),D-葡萄糖,邻-氢醌,OH,在N4位置引入硫醇(SH),产生用于直接NP锚定的[R1R2TSC-间隔基-锚定基团]缀合物。苯基,环己基,苄基,乙基和甲基用作间隔单元。作为直接NP锚定的第一个实例,两种苯基膦酸TSC衍生物都结合在TiO2NP上。[R1R2TSC-间隔-端基]缀合物,包括OH,S-Bn(Bn=苄基),NH-Boc(Boc=叔丁氧羰基),COOtBu,C=CH,或N3端基被合成用于通过酰胺与功能分子或官能化NP的潜在共价结合,酯,或三唑功能。从胺开始合成氨基硫脲H2NNH-C(S)-NR3R4,包括氨基酸,SCCl2或CS2,以及肼及其与联吡啶酮和蒽醛的缩合产生了34种新的TSC衍生物。它们在多达六个步骤中合成,总产率在10%至85%之间,并通过核磁共振波谱和质谱的组合进行了表征。UV-vis吸收和光致发光光谱使我们能够轻松地追踪联吡啶亚胺和蒽发色团。
    Thiosemicarbazones (TSCs) with their modular character (thiosemicarbazides + carbonyl compound) allow broad variation of up to four substituents on the main R1R2C=N(1)-NH-C(S)-N(4)R3R4 core and are thus interesting tools for the formation of conjugates or the functionalization of nanoparticles (NPs). In this work, di-2-pyridyl ketone was introduced for the coordination of metals and 9-anthraldehyde for luminescence as R1 and R2 to TSCs. R3 and R4 substituents were varied for the formation of conjugates. Amino acids were introduced at the N4 position to produce [R1R2TSC-spacer-amino acid] conjugates. Further, functions such as phosphonic acid (R-P(O)(OH)2), D-glucose, o-hydroquinone, OH, and thiol (SH) were introduced at the N4 position producing [R1R2TSC-spacer-anchor group] conjugates for direct NP anchoring. Phenyl, cyclohexyl, benzyl, ethyl and methyl were used as spacer units. Both phenyl phosphonic acid TSC derivatives were bound on TiO2 NPs as a first example of direct NP anchoring. [R1R2TSC-spacer-end group] conjugates including OH, S-Bn (Bn = benzyl), NH-Boc (Boc = tert-butyloxycarbonyl), COOtBu, C≡CH, or N3 end groups were synthesized for potential covalent binding to functional molecules or functionalized NPs through amide, ester, or triazole functions. The synthesis of the thiosemicarbazides H2NNH-C(S)-NR3R4 starting from amines, including amino acids, SCCl2 or CS2, and hydrazine and their condensation with dipyridyl ketone and anthraldehyde led to 34 new TSC derivatives. They were synthesized in up to six steps with overall yields ranging from 10 to 85% and were characterized by a combination of nuclear magnetic resonance spectroscopy and mass spectrometry. UV-vis absorption and photoluminescence spectroscopy allowed us to easily trace the dipyridyl imine and anthracene chromophores.
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  • 文章类型: Journal Article
    二氧化硅负载的胺吸收剂,包括通过连接氨基硅烷或灌注聚(乙烯亚胺)生产的材料,代表一类有前途的材料,用于二氧化碳捕集应用,包括直接空气和点源捕获。探索了各种二氧化硅表面处理和官能化策略以增强基于胺的固体吸附剂系统中的稳定性和CO2吸收。这里,介绍了新型乙烯基三甲氧基硅烷处理的SantaBarbara无定形-15(SBA-15)载体的合成和表征,以及与各种基于SBA-15的对照载体相比,CO2吸收的相应增强。使用先前报道的动力学模型探索了这些系统中CO2扩散与胺效率之间的关系。合成的材料用CO2和H2O等温线表征,漫反射红外傅里叶变换光谱,1HT1-T2弛豫相关NMR,和快速热循环实验。新型载体材料被证明能够实现高胺效率,接近标准SBA-15负载胺的四倍改进,同时在潮湿条件下快速循环时表现出优异的稳定性。由于聚(乙烯亚胺)负载量在各种样品中保持恒定,CO2吸收的增强归因于聚(乙烯亚胺)与载体表面相互作用的方式的差异。
    Silica-supported amine absorbents, including materials produced by tethering aminosilanes or infusion of poly(ethyleneimine), represent a promising class of materials for CO2 capture applications, including direct air and point source capture. Various silica surface treatments and functionalization strategies are explored to enhance stability and CO2 uptake in amine-based solid sorbent systems. Here, the synthesis and characterization of novel vinyltrimethoxysilane-treated Santa Barbara Amorphous-15 (SBA-15) supports and the corresponding enhancement in CO2 uptake compared to various SBA-15-based control supports are presented. The relationship between CO2 diffusion and amine efficiency in these systems is explored using a previously reported kinetic model. The synthesized materials are characterized with CO2 and H2O isotherms, diffuse reflectance infrared Fourier transform spectroscopy, 1H T1-T2 relaxation correlation NMR, and rapid thermal cycling experiments. The novel support materials are shown to enable high amine efficiencies, approaching a fourfold improvement over standard SBA-15-supported amines, while simultaneously exhibiting excellent stability when cycled rapidly under humid conditions. As the poly(ethyleneimine) loadings are held constant across the various samples, enhancements in CO2 uptake are attributed to differences in the way the poly(ethyleneimine) interacts with the support surface.
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  • 文章类型: Journal Article
    乙酰丁酚(ACE)通常用于治疗高血压和高血压。大剂量的ACE可能会产生不利影响,并可能危及生命。是的,因此,开发一个简单的,低成本,可靠,和可重复的装置,用于检测生物流体中的ACE。这项研究探索了独特的二维纳米片的潜力,例如三氧化钨(WO3)。由于存在干扰π-共轭结构的含氧官能团,氧化石墨烯(GO)通常表现出比原始石墨烯低的导电性。用单宁酸(TA)官能化GO可以部分恢复π-共轭并限制氧的量,导致导电性增强。超声波技术被用来创建WO3NFs@TA-rGO,并应用了一系列光谱和显微镜方法来检查所得WO3NFs@TA-rGO纳米复合材料的形成。在最优条件下,改进的传感器可降低检测限(0.0055μM)和良好的灵敏度(0.40μAμM-1cm-2)。它们还表现出从0.009到568.6μM的宽线性范围。制造的传感器具有显着的抗干扰性能,具有高特异性和出色的存储稳定性(RSD=4.3%),重现性(RSD=3.9%),重复性(RSD=3.3%)。最终,通过成功检测生物样品中的ACE(回收率为99.1%~99.6%),证实了传感器的功效.最后,这项研究突出了ACE检测的巨大潜力,并扩展了其在生物医学诊断和药物研究中的应用。
    Acebutolol (ACE) is commonly used to treat hypertension and high blood pressure. Large doses of ACE can have adverse effects with potentially life-threatening consequences. It is, therefore, essential to develop a simple, low-cost, reliable, and reproducible device for detecting ACE in biofluids. This study explores the potential of unique two-dimensional nano-flakes, such as tungsten trioxide (WO3). Graphene oxide (GO) typically exhibits lower electrical conductivity than pristine graphene due to the presence of oxygen-containing functional groups that interfere with the π-conjugated structure. Functionalizing GO with tannic acid (TA) can partially reinstate the π-conjugation and limit the amount of oxygen, resulting in enhanced electrical conductivity. Ultrasonic techniques were utilized to create WO3 NFs@TA-rGO, and a range of spectroscopic and microscopic methods were applied to examine the formation of the resulting WO3 NFs@TA-rGO nanocomposites. Under optimal conditions, modified sensors resulted in lower limits of detection (0.0055 μM) and good sensitivity (0.40 μA μM-1 cm-2). They also exhibited a broad linear range spanning from 0.009 to 568.6 μM. Fabricated sensors have significant anti-interference properties with high specificity and excellent storage stability (RSD = 4.3 %), reproducibility (RSD = 3.9 %), and repeatability (RSD = 3.3 %). Ultimately, the sensor\'s efficacy was confirmed through the successful detection of ACE in biological samples (with recoveries ranging from 99.1 to 99.6 %). Lastly, this study highlights the substantial potential of ACE detection and extends its applications in biomedical diagnostics and pharmaceutical research.
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  • 文章类型: Journal Article
    碳纳米纤维是一种新型的碳材料。获得它们的方法之一是碳化聚合物前体。它们在许多领域都很有吸引力,包括医学,由于在宽范围内修改其属性的可能性。例如,碳化过程的条件导致产生具有设计结构和表面参数的材料。在目前的工作中,纳米前体是聚丙烯腈(PAN)纤维。测试了通过在1000°C下碳化PAN前体获得的两种类型的碳纤维。第一个静电纺丝碳纳米纤维(ESCNFs)具有细胞毒性,而第二个ESCNF-f在功能化后具有生物相容性。从拉曼测试获得的参数在测试材料之间没有明显的区别。多波长拉曼研究,使用二维相关光谱法(2D-COS)进行分析,将激光能量视为外部干扰,显示两种纤维结构之间的差异。2D-COS表明结构类似于石墨系统,没有无序的碳形式,是无毒的。
    Carbon nanofibers are a new type of carbon materials. One of the methods of obtaining them is the carbonization of a polymer precursor. They are attractive in many areas, including medicine, due to the possibility of modifying their properties in a wide range. For example, the conditions of the carbonization process result in the creation of materials with designed structures and surface parameters. In the current work, the nanoprecursor was polyacrylonitrile (PAN) fibers. Two types of carbon fibers obtained by carbonization of the PAN precursor at 1000 °C were tested. The first electrospun carbon nanofibers (ESCNFs) were cytotoxic, while the second ESCNF-f were biocompatible after functionalization. The parameters obtained from Raman tests did not clearly discriminate between the tested materials. Multiwavelength Raman studies, analyzed using the two-dimensional correlation spectroscopy (2D-COS), treating the laser energy as an external disturbance, showed a difference between both fibrous structures. 2D-COS indicates that structures resembling graphite systems, devoid of disordered carbon forms, are nontoxic.
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  • 文章类型: Journal Article
    由SARS-CoV-2产生的COVID-19已经严重影响了全球的医疗保健系统。这一流行病凸显了疫苗开发的迫切需要。除了传统的疫苗接种模型,其中包括活减毒,重组蛋白,和灭活疫苗,纳米疫苗为推进疫苗研究和提供方便的替代品提供了一个独特的机会。这篇综述重点介绍了许多广泛使用的纳米颗粒疫苗载体,概述了它们的优点和缺点,并研究了预防SARS-CoV-2的纳米颗粒疫苗的最新进展。它还全面概述了纳米颗粒疫苗的许多优点,包括增强的宿主免疫反应,多价抗原递送,和有效的药物输送。主要目的是为创新抗病毒疫苗的开发提供参考。
    COVID-19, generated by SARS-CoV-2, has significantly affected healthcare systems worldwide. The epidemic has highlighted the urgent need for vaccine development. Besides the conventional vaccination models, which include live-attenuated, recombinant protein, and inactivated vaccines, nanovaccines present a distinct opportunity to progress vaccine research and offer convenient alternatives. This review highlights the many widely used nanoparticle vaccine vectors, outlines their benefits and drawbacks, and examines recent developments in nanoparticle vaccines to prevent SARS-CoV-2. It also offers a thorough overview of the many advantages of nanoparticle vaccines, including an enhanced host immune response, multivalent antigen delivery, and efficient drug delivery. The main objective is to provide a reference for the development of innovative antiviral vaccines.
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  • 文章类型: Journal Article
    老年痴呆症,最常见的神经退行性疾病,影响全世界超过6000万人,这个数字估计到2050年会翻一番。阿尔茨海默病的特点是进行性记忆丧失,行为障碍,和情绪变化,以及病人的日常生活受到干扰。虽然有一些活性分子可以通过阻止疾病的进展而有益,血脑屏障和其他生理屏障阻碍了它们的传递,因此,疾病的适当管理。因此,有效靶向并克服血脑屏障到达目标脑区的药物递送系统将提高治疗效果。脂质体是由磷脂双层结构组成的亲脂性载体,模拟血脑屏障的生理脂质层,并使药物更好地输送到大脑。鉴于纯脂质体可能比功能化脂质体具有更低的靶向亲和力,用乳铁蛋白等基团修饰,聚(乙二醇),和转铁蛋白可以提高特异性。在这个小型审查中,我们总结了使用脂质体治疗阿尔茨海默病的文献,专注于脂质体的官能化部分。此外,还讨论了大脑输送中的挑战。
    Alzheimer\'s disease, the most common neurodegenerative disease, affects more than 60 million people worldwide, a number that is estimated to double by 2050. Alzheimer\'s disease is characterized by progressive memory loss, the impairment of behavior, and mood changes, as well as the disturbed daily routine of the patient. Although there are some active molecules that can be beneficial by halting the progression of the disease, the blood-brain barrier and other physiological barriers hinder their delivery and, consequently, the appropriate management of the disease. Therefore, drug delivery systems that effectively target and overcome the blood-brain barrier to reach the targeted brain area would improve treatment effectiveness. Liposomes are lipophilic carriers that consist of a phospholipid bilayer structure, simulating the physiological lipidic layer of the blood-brain barrier and enabling better delivery of the drug to the brain. Given that pure liposomes may have less targeting affinity than functionalized liposomes, modification with groups such as lactoferrin, poly(ethylene glycol), and transferrin may improve specificity. In this mini-review, we summarize the literature on the use of liposomes for the treatment of Alzheimer\'s disease, focusing on the functionalization moieties of liposomes. In addition, challenges in brain delivery are also discussed.
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  • 文章类型: Journal Article
    以石油为基础的包装已经在上个世纪发展,以运输和保护许多产品,无论应用领域如何(食品,电子,化妆品,休闲,等。).这种保护有利于经济增长,对我们社会的发展非常有用,限制食物浪费和产品变质,从而避免强烈的环境影响。许多国家现在已经考虑到环境问题,颁布了几项立法来避免或限制塑料废物。在这种情况下,纤维素成为包装应用的替代材料,因为它是基于生物的,可生物降解,并且在大多数情况下可以在现有的流中回收。然而,大多数现有的纤维素包装是基于卷对卷的2D产品或胶合盒,不适合在3D形状的包装中替代塑料。最近,由于原材料和工艺的新调整,人们对模塑纤维素的兴趣呈指数级增长。或者,研究小组和公司试图使注塑成型适应纤维素基包装解决方案的生产。本次审查首次详细介绍了该方向的各种流程和近期工作。在提出纤维素的基础知识之后,这项工作的重点是不同类型的模塑纤维素和生产3D纤维素基材料的新策略。
    Petroleum-based packaging have been developed during the last century to transport and protect many products, regardless of the field of applications (food, electronics, cosmetics, leisure, etc.). Such protection has been very useful for the development of our society by favoring economic growth, limiting food waste and product deterioration, and consequently avoiding strong environmental impacts. An environmental concern has now been taken into consideration by numerous countries, with several legislations being promulgated to avoid or limit plastic waste. In this context, cellulose emerges as an alternative material for packaging applications since it is bio-based, biodegradable, and in most cases recyclable in an existing stream. However, most of the existing cellulose packaging is based on roll-to-roll 2D products or plied boxes and is not suitable to substitute plastics in 3D-shaped packaging. Recently, the interest in molded cellulose has increased exponentially thanks to new adaptations of raw materials and processes. Alternatively, research groups and companies try to adapt the injection molding to the production of cellulose-based packaging solutions. This review details for the first time the various processes and recent works in this direction. After proposing the basics of cellulose, this work focuses on the different types of molded cellulose and the novel strategies to produce 3D cellulose-based materials.
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  • 文章类型: Journal Article
    木质素光催化转化为增值化学品,尤其是那些官能化分子代表了可持续和环境友好发展的最重要策略之一。在温和的光催化条件下将木质素中的C-C键裂解以将木质素精制成有用的分子是有意义的但具有挑战性的。同时,在解聚过程中,将各种官能团组装成活性木质素片段具有很大的挑战性。在这里,在可见光照射下使用廉价的铁催化剂,木质素中Cα-Cβ键的高选择性和有效裂解是通过配体到金属的电荷转移(LMCT)和氢原子转移(HAT)过程实现的。所产生的基于木质素片段的自由基中间体的随后的发散官能化使得能够有效地形成不同的官能化分子。该方法对于天然木质素中的Cα-Cβ键的裂解也是有效的,产生两种确定的苯甲醛单体,总收率为8.7wt%。
    The photocatalytic conversion of lignin into value-added chemicals especially those functionalized molecules represent one of the most important strategies for sustainable and environmental-friendly development. Cleavage of C-C bonds in lignin under mild photocatalytic conditions for refining lignin into useful molecules is meaningful but challenging. Meanwhile, the assembly of diverse functional groups into active lignin fragments during the depolymerization is of great challenging. Herein, using cheap iron catalysts under visible light irradiation, the highly selective and efficient cleavage of Cα-Cβ bond in lignin is realized via ligand-to-metal charge transfer (LMCT) and hydrogen atom transfer (HAT) processes. The subsequent divergent functionalization of generated lignin fragment-based radical intermediates enables an efficient formation of diverse functionalized molecules. This method is also effective for cleavage of Cα-Cβ bond in native lignin, yielding two identified benzaldehyde monomers in a total yield of 8.7 wt%.
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  • 文章类型: Journal Article
    具有配体的量子点(QD)和量子棒(QRs)的官能化对于它们跨各种域的进一步实际应用是必不可少的。脱水辅助官能化(DAF)是一种通用方法,适用于对QD和QR表面具有亲和力的各种亲水性配体。这种方法通过有效地将这些配体转移到QD和QRs的表面上,促进了快速的一锅法配体交换和致密修饰。这项研究证明了DAF在制备手性QRs中的功效,工程量子点的表面电荷,利用QR聚合,并将致密DNA缀合到无镉InP/ZnSQD上。因此,DAF提供了适用于各种应用的QD和QR的亲水配体官能化的通用解决方案。
    Functionalization of quantum dots (QDs) and quantum rods (QRs) with ligands is essential for their further practical application across various domains. Dehydration-assisted functionalization (DAF) is a versatile method applicable to a wide range of hydrophilic ligands with an affinity to the surface of QDs and QRs. This approach facilitates rapid one-pot ligand exchange and dense modification by efficiently transferring these ligands onto the surface of QDs and QRs. This study demonstrates the efficacy of DAF in preparing chiral QRs, engineering the surface charge of QDs, utilizing QR aggregates, and conjugating dense DNA onto cadmium-free InP/ZnS QDs. DAF therefore offers a versatile solution for hydrophilic ligand functionalization of QDs and QRs applicable to diverse applications.
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