磁性水凝胶作为药物载体的应用研究进展

磁性水凝胶是一类同时具有磁性材料、高分子材料及水凝胶的性质特点的无机/有机复合材料。因具有优良的磁学性能及生物相容性,其作为新一代的药物载体可以实现磁响应、磁靶向及磁热疗等功能,在药物控制释放领域具有广阔的应用前景。对磁性水凝胶的制备方法及其在药物载体领域的研究情况进行了综述,详细介绍了磁性水凝胶作为药物载体的两种药物释放机理(ON/OFF模型及热敏释放原理),及其在磁靶向药物控释、磁热疗和磁共振成像方面的应用研究现状。     

聚苯胺/磁性纳米复合材料的制备及应用

聚苯胺/磁性纳米复合材料具有电磁性,有广泛的应用前景,已成为纳米材料研究的热点之一.主要介绍了聚苯胺/磁性纳米复合材料的制备方法与材料性质及其应用,分析了原位聚合、溶胶-凝胶法、自组装技术等制备方法的优缺点,并指出了聚苯胺/磁性纳米复合材料的研究方向.     

磁性气凝胶的研究进展

磁性气凝胶以其优异的性能受到越来越多的关注。目前,磁性气凝胶主要采用先将磁功能化材料分散到溶胶中,经凝胶、老化、超临界干燥等工艺制得。磁功能化材料主要是指具有磁性的纳米材料,其中应用最多的是铁酸类,尤其以超顺磁性Fe_3O_4的使用最为广泛。而磁性气凝胶的结构和性能因磁功能化纳米材料、气凝胶基体的不同而变化。无机磁性气凝胶的基体主要是氧化硅、氧化钛等气凝胶,主要研究磁性颗粒与气凝胶基体的相互作用机理,以及对材料的结构、性能的影响。而有机磁性气凝胶基体主要是石墨烯、碳等柔性气凝胶,主要应用在催化、吸附、生物分离等领域,具有磁性分离,以及使用效率、重复性能优异等特点。综述了上述磁性气凝胶的研究进展,介绍了磁性气凝胶材料常用的制备方法、性能以及应用前景。     

磁诱导高取向水凝胶的构筑及功能

磁诱导制备高取向水凝胶可赋予其各向异性的支持、驱动、传输、结构等特殊功能,从而使得高取向水凝胶成为生物工程材料应用的理想候选者.同时,磁诱导制备方法不受限于材料尺寸且取向方向容易控制,是目前较为简单、有效的制备高取向水凝胶的方法之一.本文主要从各向异性偶极-偶极作用力和磁能角度分析了磁性纳米填料及非磁性材料在磁场作用下的取向机理;阐述了磁诱导取向水凝胶在仿生学领域的最新研究进展;最后,对磁诱导构建取向水凝胶的未来研究和发展进行了展望.     

磁性水凝胶的制备与应用

介绍了国内外磁性水凝胶的制备和应用,并展望了其在涂料行业的应用。     

磁性氧化铁纳米微粒的制备与应用

磁性氧化铁纳米粒是一种多功能材料,在药学、医学、催化化学和磁记录材料等领域具有广泛的应用价值。介绍了目前国内外几种广泛制备磁性氧化铁纳米微粒的方法,包括溶胶-凝胶法、沉淀法、微乳液法、水热法和模板法等,比较了它们各自的优缺点,还介绍了磁性氧化铁纳米微粒近年来的研究与应用情况并展望了其发展方向。     

磁性氧化铁纳米微粒的制备与应用

磁性氧化铁纳米粒是一种多功能材料，在药学、医学、催化化学和磁记录材料等领域具有广泛的应用价值。介绍了目前国内外几种广泛制备磁性氧化铁纳米微粒的方法，包括溶胶-凝胶法、沉淀法、微乳液法、水热法和模板法等，比较了它们各自的优缺点，还介绍了磁性氧化铁纳米微粒近年来的研究与应用情况并展望了其发展方向。     

光交联丝素蛋白水凝胶的制备及生物医学应用

水凝胶是一类物理化学性质接近软组织的先进材料,已有众多聚合物用于水凝胶的制备。丝素蛋白由于具有优异的生物相容性、生物可降解性和易于制备成各种形式的材料等优点,在生物医学领域中具有广泛的应用,其中水凝胶是丝素蛋白在生物医学中应用的重要形式。由于分子的独特结构,丝素蛋白可以通过多种方法形成水凝胶。近年来,光交联水凝胶由于具有制备条件温和、副产物少、反应过程容易控制等优点,逐步成为研究的热点。首先对丝素蛋白的分子结构和特性进行了介绍,总结了丝素蛋白水凝胶的制备方法,重点阐述了光交联丝素蛋白水凝胶的研究现状,并讨论了它们在生物医学领域的应用,最后对光交联丝素蛋白水凝胶未来发展方向进行了展望。     

纳米Fe3O4/聚乙烯醇磁性水凝胶的制备及性能

利用化学方法制得了纳米Fe3 O4粒子,然后将其与聚乙烯醇(PVA)的胶态溶液共混,通过冻融法制备了纳米Fe3O4/PVA磁性水凝胶.采用综合热分析仪、拉伸试验机及ppms-9综合物性检测系统对磁性水凝胶进行了表征和测试.结果表明,纳米Fe3O4粒子的加入会降低磁性水凝胶的热稳定性;磁性水凝胶的力学性能和磁学性能随纳米Fe3O4含量及冻融次数的改变而显著变化.     

水凝胶在医学领域的热点研究及应用

水凝胶是一种具有三维网络结构的新型功能高分子材料.它以其含水量高、溶胀快、柔软、具有橡胶般的粘稠性和良好的生物相容性等而得到广泛应用及研究.主要介绍近几年水凝胶在生物医学领域的研究热点及水凝胶在生物医学领域应用的最新进展.     

壳聚糖水凝胶的制备及其在药物释放中的应用

水凝胶作为性能良好的载体,在药物的控释、组织工程等领域有着广泛的应用。壳聚糖是一类天然的带正电荷的碱性多糖,由其形成的水凝胶具有较好的生物相容性、生物降解性、抗菌和低细胞毒性,因此,壳聚糖水凝胶有着良好的生物应用前景。本文综述了壳聚糖水凝胶的制备方法(包括物理交联法和化学交联法),在物理交联法部分着重介绍了离子化合物及聚电解质分子与壳聚糖通过离子交联形成水凝胶,以及利用分子链间的疏水作用形成壳聚糖水凝胶的方法;而在化学交联法部分介绍了合成壳聚糖水凝胶的化学手段,包括交联剂、光照辐射和酶的使用。继而概述了壳聚糖水凝胶在药物缓释应用方面的研究进展,包括温度、pH值和电场响应的药物控释体系。最后展望了壳聚糖水凝胶未来的发展前景。     

高强度水凝胶的制备及其研究进展

水凝胶因其拥有较高的溶胀比和极高的含水率,被广泛应用于各种领域,但力学性能较弱的缺点限制了其在组织工程、软体机器人、可穿戴电子设备等高负载领域的发展。综述了近年来纳米复合水凝胶、双网络水凝胶、大分子微球复合水凝胶、疏水缔合水凝胶等高强度水凝胶的制备方法及研究进展;讨论了各类型高强水凝胶的特点并指出了目前研究中存在的问题;同时,对高强度水凝胶未来的研究方向进行了展望。     

高强度水凝胶纳米复合材料的研究进展

水凝胶是化学或物理交联而成的具有三维网络结构的高分子材料,其高分子网络中含有大量的水并能保持一定的形状,是一种特殊的半固体材料。水凝胶由于具有许多优异的性质,在工业、农业、生物医学领域得到广泛重视,然而传统水凝胶的力学性能差,限制了其应用。因此提高水凝胶力学强度的研究吸引了国内外众多研究者的关注。总结了近年来几种主要类别的高强度水凝胶纳米复合材料的实验及理论研究工作,重点分析了纳米复合凝胶在力学性能方面的研究结果,并对其未来的发展进行了展望。     

Carbon Dot-Based Hydrogels: Preparations,Properties, and Applications (Small 17/2023)

Hydrogels have extremely high moisture content, which makes it very soft and excellently biocompatible. They have become an important soft material and have a wide range of applications in various fields such as biomedicine, bionic smart material, and electrochemistry. Carbon dot (CD)-based hydrogels are based on carbon dots (CDs) and auxiliary substances, forming a gel material with comprehensive properties of individual components. CDs embedding in hydrogels could not only solve their aggregation-caused quenching (ACQ) effect, but also manipulate the properties of hydrogels and even bring some novel properties, achieving a win–win situation. In this review, the preparation methods, formation mechanism, and properties of CD-based hydrogels, and their applications in biomedicine, sensing, adsorption, energy storage, and catalysis -are summarized. Finally, a brief discussion on future research directions of CD-based hydrogels will be given.     

丝素蛋白水凝胶材料在组织工程中的应用研究进展

组织工程技术是有望从根本上解决组织或器官损伤及实现功能重建的前沿技术,其关键之一是制备具有良好生物相容性和生物降解性的支架材料。水凝胶由于具有众多良好的特性,成为组织工程研究中一种优良的支架材料。丝素蛋白水凝胶由于独特的性质、多样化的成胶方式以及优异的可加工性成为了支架材料研究的热点,备受学者的青睐并涌现出了大量的研究成果。本文在阐明丝素蛋白凝胶原理的基础上,回顾了目前较为成熟的凝胶化方法,随后重点综述了丝素蛋白水凝胶在组织工程中的研究进展,最后进行了总结和展望,以期为相关领域的研究者提供参考和借鉴。     

Hydrogels for Soft Machines

Hydrogels have applications in surgery and drug delivery, but are never considered alongside polymers and composites as materials for mechanical design. This is because synthetic hydrogels are in general very weak. In contrast, many biological gel composites, such as cartilage, are quite strong, and function as tough, shock‐absorbing structural solids. The recent development of strong hydrogels suggests that it may be possible to design new families of strong gels that would allow the design of soft biomimetic machines, which have not previously been possible.     

Non-destructive characterization of hydrogels

Hydrogels have been prepared by a freezing–thawing procedure and investigations made of the effect of both number of freezing–thawing cycles and different content of hyaluronic acid (HA) on the mechanical properties of the PVA-HA hydrogels using non-destructive testing. The bulk elastic modulus K of hydrogels has been determined by pulse-echo measurements. It is noted that hydrogel elastic properties improve with the number of the cycles in PVA-HA 100/0; on the other hand samples with a high HA (1000000 molecular weight) content, beyond the third cycle, seem to be unaffected by the number of cycles. A bulk elastic modulus fall-off is then observed in samples submitted to an additional overnight freezing between two subsequent cycles. K increases in hydrogels with the highest HA content, when samples undergo pulse-echo measurements soon after their preparation. When hydrogels reach equilibrium, after having been kept in deionized water for 12 h, K values are lower, showing a nearly constant behaviour with different PVA-HA ratios and cycles. Furthermore, by means of scanning laser acoustic microscopy (SLAM) defects have been detected in the hydrogels. In samples which have reached equilibrium, SLAM images show that these defects disappear in PVA-HA hydrogels.     

Design and Applications of Photoresponsive Hydrogels

Hydrogels are the most relevant biochemical scaffold due to their tunable properties, inherent biocompatibility, and similarity with tissue and cell environments. Over the past decade, hydrogels have developed from static materials to “smart” responsive materials adapting to various stimuli, such as pH, temperature, chemical, electrical, or light. Light stimulation is particularly interesting for many applications because of the capability of contact‐free remote manipulation of biomaterial properties and inherent spatial and temporal control. Moreover, light can be finely adjusted in its intrinsic properties, such as wavelength and intensity (i.e., the energy of an individual photon as well as the number of photons over time). Water is almost transparent for light in the photochemically relevant range (NIR–UV), thus hydrogels are well‐suited scaffolds for light‐responsive functionality. Hydrogels' chemical and physical variety combined with light responsiveness makes photoresponsive hydrogels ideal candidates for applications in several fields, ranging from biomaterials, medicine to soft robotics. Herein, the progress and new developments in the field of light‐responsive hydrogels are elaborated by first introducing the relevant photochemistries before discussing selected applications in detail.     

Capillary Origami Inspired Fabrication of Complex 3D Hydrogel Constructs

Hydrogels have found broad applications in various engineering and biomedical fields, where the shape and size of hydrogels can profoundly influence their functions. Although numerous methods have been developed to tailor 3D hydrogel structures, it is still challenging to fabricate complex 3D hydrogel constructs. Inspired by the capillary origami phenomenon where surface tension of a droplet on an elastic membrane can induce spontaneous folding of the membrane into 3D structures along with droplet evaporation, a facile strategy is established for the fabrication of complex 3D hydrogel constructs with programmable shapes and sizes by crosslinking hydrogels during the folding process. A mathematical model is further proposed to predict the temporal structure evolution of the folded 3D hydrogel constructs. Using this model, precise control is achieved over the 3D shapes (e.g., pyramid, pentahedron, and cube) and sizes (ranging from hundreds of micrometers to millimeters) through tuning membrane shape, dimensionless parameter of the process (elastocapillary number C_e), and evaporation time. This work would be favorable to multiple areas, such as flexible electronics, tissue regeneration, and drug delivery.     

自愈合水凝胶的制备及其在食品包装中的应用

水凝胶因具有较高的延展性和良好的生物相容性,在食品包装领域受到了越来越多的关注。然而水凝胶作为一种软材料,在运输、搬运和储存过程中容易受到外界因素的影响而造成损坏,对食品安全构成巨大的威胁。自愈合水凝胶是一种在物理损伤后可以恢复到原始结构和功能的智能水凝胶,可以有效地解决上述问题。综述了基于可逆共价交联和可逆非共价交联自愈合水凝胶的修复机制与制备方法,介绍了其在食品包装领域的潜在应用,最后总结了自愈合水凝胶现存的问题和未来发展方向。