智能型高分子水凝胶在药物控释中的应用研究进展

智能型高分子水凝胶因为能感应到外界环境因素的变化,并且发出响应—凝胶的体积或其他性质发生显著变化,从而导致药物可在定点位置,定时、定量的释放,所以近年来受到普遍重视。本文综述了近年来智能型高分子水凝胶中温度敏感型、pH敏感型以及葡萄糖、电场、磁场、光、微波等敏感型水凝胶及其在药物控释中的应用,介绍了其控释作用机理及应用实例,并从如何提高水凝胶的力学强度和快速响应性能角度,总结了高强度及快速响应水凝胶的一些研究成果。最后文章还指出了目前环境刺激响应型水凝胶的不足之处及今后发展研究的方向。     

智能型水凝胶研究现状及改性进展

综述了智能型水凝胶的研究背景、相关理论与实际现状。并从4个主要方面综述了近年来智能型水凝胶改性的研究进展。从各个角度出发，论述了智能型水凝胶的作用、地位和意义，并对它的未来进行了展望。     

智能水凝胶的应用

智能水凝胶对于外界微小的物理化学刺激,如温度、电场、磁场、光、pH、离子强度或压力等能够感知并在响应过程中有显著的溶胀行为或响应性。本文重点介绍了智能水凝胶及与之密切相关的智能型大分子在药物控释、组织工程、活性酶的固定、调光材料等方面的应用。     

磺化纤维素水凝胶电刺激响应行为的研究

以环氧氯丙烷为交联剂,制备了纤维素水凝胶,用浓硫酸对其进行磺酸改性,制备出一种磺化纤维素水凝胶,并研究了该凝胶的溶胀性能、电刺激响应行为。结果表明,该凝胶在NaCl溶液中其平衡溶胀率随NaCl离子强度的增大而减小。在NaCI溶液中于非接触直流电场作用下,凝胶向电场负极弯曲,弯曲速度和应变随外加电压的增加而增大,并随NaCl离子强度的增大于0.03mol／kg处出现最大值、在循环电场作用下,其电刺激响应行为具有良好的可逆性,     

壳聚糖温敏水凝胶研究进展

温敏性水凝胶是一种智能型高分子水凝胶,能在应答外界温度刺激时发生自身相变,具有良好的生物相容性与力学性能,被广泛应用于组织工程、细胞包封、药物传递等方面。壳聚糖是一种在自然界中大量存在的多糖,因具有低细胞毒性与生物相容性,常作为药物缓释体被广泛应用。重点对近几年壳聚糖温敏水凝胶的相关研究进行综述。     

新型高强度智能水凝胶的研究进展

智能型水凝胶是一类具有广泛应用前景的功能高分子材料,但是由于智能水凝胶的机械强度较低,很大程度上限制了其应用,为此近年来许多科学家围绕这一课题开展了大量的研究工作.综述了3种具有不同增强机理的高强度智能水凝胶的研究进展.     

智能型水凝胶材料及其应用

本文综述了智能型水凝胶的制备方法及该凝胶对环境的刺激响应性,重点介绍了它的温敏效应、pH敏效应、压敏效应、光敏效应及电敏效应。最后介绍了它的应用现状。     

聚乙烯吡咯烷酮半互穿网络智能凝胶的合成和电场行为研究

利用化学交联法,制备了由聚乙烯吡咯烷酮(PVP)和丙烯酰胺(Am)、丙烯酸(AA)复合的具有半互穿网络(Semi-IPNs)结构的高分子水凝胶。研究了凝胶在直流电场作用下NaCl溶液中的溶胀、弯曲行为及交联剂含量、PVP含量对水凝胶的溶胀性质、拉伸强度的影响。结果表明凝胶的最大弯曲率随着时间和电场强度的增加而增大,随溶液离子浓度的增加呈现出最大值。增加PVP可以提高拉伸强度降低弯曲度,适当增加交联剂,可以加强拉伸强度108.51%,降低溶胀度68.29%。     

智能水凝胶的研究进展

智能水凝胶是指在外界环境(如温度、pH值、电场等)发生变化时,性质随之发生相应改变的水凝胶,即具有环境响应性。水凝胶尤其是智能水凝胶由于其迷人的性质及潜在的应用引起广大科技工作者的研究兴趣。根据智能水凝胶对环境的响应情况,作者详细介绍了pH敏感性水凝胶、温度敏感性水凝胶、光敏感性水凝胶、电场敏感性水凝胶、磁敏感性水凝胶、盐敏感性水凝胶、化学物质敏感性水凝胶以及多重敏感性水凝胶的研究情况,同时对智能水凝胶的研究方向和应用前景进行了展望。     

智能水凝胶应用研究进展

智能水凝胶是指在外界环境（如温度、pH、电场、溶剂性质、光强度和光波长、压力、离子强度等）发生变化时,性质随之发生相应变化的水凝胶,即具有环境响应性。作者详细介绍了智能水凝胶在药物控制释放、组织工程、物质分离、酶的固载及调光材料5个方面的应用研究情况。并对智能水凝胶未来的研究方向及应用前景进行了展望。     

氧化石墨烯复合水凝胶研究进展

氧化石墨烯（GO）是一种廉价易得、水中易分散、光热性能好的二维纳米材料。将氧化石墨烯与水凝胶结合,可以赋予水凝胶许多纳米材料的优异性能,大大拓展水凝胶的潜在应用。详细介绍了具有力学性能、光热转化性能、自修复性能的氧化石墨烯复合水凝胶及其在智能驱动器、细胞骨架等方面的应用,并对其未来研究方向提出展望和设想。     

电场敏感智能水凝胶的研究进展

水凝胶对于环境微小的物理化学刺激,如温度、pH值,离子强度、电场、磁场,光、压力等能够通过感知和自身作功来响应外界环境变化,因此水凝胶具有"智能凝胶"、"软性机械"之称.在众多外界响应条件中,电场由于易操作易调控等优点使得电场响应水凝胶具有更广阔的应用前景.本文对近年来已见报道的几类典型的电场敏感水凝胶进行了较为详细的综述.同时介绍了静电场、渗透压等电场敏感水凝胶的响应机理及其在人工爬虫、化学阀和仿生驱动器等方面的应用.     

Novel Biodegradable pH/Thermosensitive Hydrogels: Part 1. Preparation and Characterization

A series of biodegradable and pH/thermosensitive hydrogels based on monomethoxyl poly(ethylene glycol) (MPEG), poly(?-caprolactone) (PCL), methylacrylic acid (MAA), and N-Isopropylacrylamide (NIPAAm) were prepared by UV-initiated free radical polymerization method. Swelling behavior and hydrolytic degradable behavior in aqueous medium with different pH values and pH/thermosensitivity of the hydrogels were studied in detail. The prepared biodegradable pH/thermo-sensitive hydrogels based on PCL, MPEG, MAA, and NIPAAm may have great potential application in smart drug delivery system.     

Electrical behavior of chitosan and poly(hydroxyethyl methacrylate) hydrogel in the contact system

Semi‐interpenetrating polymer networks (semi‐IPNs), as polymer hydrogels composed of chitosan and poly(hydroxyethyl methacrylate) (PHEMA), exhibiting electrical‐sensitive behavior, were prepared. The swelling behavior of the chitosan/PHEMA hydrogels was studied by immersing the gels in various concentrations of aqueous NaCl solution. The electrical responses of the semi‐IPN hydrogel, in applied electric fields, were also investigated. When the semi‐IPN hydrogels were swollen, where one electrode was placed in contact with the gel and the other fixed 30 mm apart from one, they exhibited bending behavior on the application of an electric field on a contact system. The electroresponsive behavior of the present semi‐IPN was also affected by the electrolyte concentration of the external solution. The semi‐IPN also showed various degrees of increased bending behavior depending on the electric stimulus. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 915–919, 2004     

环境刺激响应型高强度智能水凝胶研究进展

环境刺激响应型智能水凝胶能够对外界环境因素的变化产生显著的体积或其他特性的变化,且其性质和结构与生物组织类似,有望应用于人工软骨、人造肌肉、组织工程等领域,引起了广泛的关注。提高环境刺激响应型智能水凝胶的力学性能是智能水凝胶应用研究的重要方向之一。本文综述了近年来环境刺激响应型高强度智能水凝胶的研究进展,简述了高强度智能水凝胶的网络结构的构建策略与方法,分析了其具备高力学性能的机理,重点介绍了4类不同结构的高强度智能水凝胶,即超低交联结构水凝胶、纳米颗粒复合水凝胶、拓扑结构水凝胶以及双网络结构水凝胶,最后讨论了环境刺激响应型高强度智能水凝胶在面向应用的研究过程中仍然需要解决的关键科学问题,如智能水凝胶的环境刺激与力学性能的博弈效应以及响应环境刺激前后的力学性能差异等。     

具有快速响应特性的环境响应型智能水凝胶的研究进展

环境响应智能水凝胶应用于化学传感器、化学微阀、人造肌肉、药物控释载体、物质分离等领域时常常需要快速响应特性,提高智能水凝胶的响应速率成为了智能水凝胶研究领域的重要课题之一。本文主要综述了具有快速响应特性的环境响应智能水凝胶的构建策略与方法,重点介绍了3类具有不同结构的快速响应型智能水凝胶,即具有多孔结构的快速响应智能水凝胶、具有梳状结构的快速响应智能水凝胶以及具有微球复合结构的快速响应智能水凝胶。     

Preparation and characterization of PVA films with magnetic nanoparticles: The effect of particle loading on drug release behavior

This article deals with the drug release behavior of theophylline (Th) from poly(vinyl alcohol) (PVA) hydrogels, prepared with magnetic nanoparticles at different particle loadings. These biocompatible matrices were obtained by incorporating different amounts of an aqueous ferrofluid into PVA hydrogels, loaded with Th as a marker for drug‐delivery studies. PVA films with magnetic particles proved to be magnetic field‐responsive materials as the drug release decreased through the application of a relative low and uniform magnetic field for particle concentrations of 0.9% w/w or higher. Moreover, the percentage of restriction of drug release is found to be correlated with particle loading. The in vitro release profiles were analyzed by applying a semiempirical power law to obtain the kinetic parameters. The value of the release exponent was found to be in the range 0.54–0.56 in all experiments, which thus indicates a predominant diffusional mechanism for drug release from these smart magnetic hydrogels. This effect suggests the possibility of modulating the release behavior by controlling the particle content in the preparation of the composites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Preparation of hydrogels composed of poly(vinyl alcohol) and polyethyleneimine and their electrical response

Semi‐ and full‐interpenetrating polymer network (IPN) hydrogels composed of poly(vinyl alcohol) and polyethyleneimine (PEI) were prepared to investigate the bending behavior under the electric response. To find out the characteristics of the hydrogel in the medium, swelling ratio, and rate and water state of the hydrogels were measured. The swelling ratio of the semi‐IPN hydrogels increased with PEI content in the matrix, whereas that of full‐IPN hydrogels dramatically decrease with increase of PEI contents in the hydrogels. In the water state of hydrogel, the bound water and free water of semi‐IPN hydrogels increased with PEI weight ratio. The full‐IPN hydrogels show the lower free water content in comparison with the semi‐IPN hydrogel. The IPN hydrogels exhibited bending angle change in response to external stimulus such as voltage, the bending angle increased with PEI concentration. In addition, the repeated bending behaviors according to the magnitude of the applied electric field revealed that the bending angle is reversible without collapse of formation of hydrogel in all samples. Thus, the hydrogels will be useful as novel modulation systems in the field of artificial organ and matrix for drug delivery. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

智能水凝胶研究进展

作为一种智能高分子材料,智能水凝胶具有良好的应用前景,本文重点介绍了刺激响应型智能水凝胶、高强智能水凝胶及自愈合智能水凝胶的结构特征、性能特点及研究现状,并对智能水凝胶的未来发展进行了展望。     

水凝胶的制备

主要叙述了水凝胶的各种制备方法,包括化学方法和物理方法,不同的高分子原料和不同的制备方法所得到的水凝胶的性质会有所差异,可以满足不同领域的应用需求。