智能水凝胶在药物控释系统的应用及研究进展

简述了智能水凝胶在药物控释系统中的应用及国内外研究进展。重点阐述了高分子水凝胶中的pH敏感、温敏、电场敏感、光敏感水凝胶和小分子水凝胶的结构、性质,以及作为释药载体在给药系统中的研究应用。     

智能水凝胶的制备及其在生物医学中的应用

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。本文介绍了智能水凝胶的分类及其合成方法,同时综述了智能水凝胶在药物控释、医用敷料、组织工程、角膜接触镜材料以及作为组织充填材料方面的应用,并对其发展趋势及应用前景作了简单的评述。     

壳聚糖智能水凝胶在生物材料领域的应用

壳聚糖智能水凝胶对于外界微小的物理化学刺激,如温度、pH、电场等能够感知并在响应过程中有显著的溶胀行为或响应性.介绍了壳聚糖智能水凝胶的制备及其在药物控释、伤口辅料和组织工程等方面的应用,并展望了其未来.     

环糊精水凝胶的研究进展

综述了环糊精水凝胶的合成方法及环糊精单元的引入对水凝胶的包合性能、响应速率及不同药物释放性能的影响。结果表明,将具有包合作用的环糊精单元引入到水凝胶基质中,不仅改善了水凝胶的载药能力,而且改变了药物-聚合物之间的作用力及药物在聚合物基体中的状态,从而改变了药物的控制释放性能。     

冷冻聚合法制备多孔P(NIPAm-Co-AAm)水凝胶及其性能研究

采用冷冻聚合法制备了多孔结构的P(NI-PAm-co-AAm)智能水凝胶,利用扫描电子显微镜和比表面积分析仪对水凝胶的多孔结构和表面形貌进行了测试,并测定了水凝胶的平衡溶胀比、溶胀和退溶胀动力学,研究了不同预冷冻聚合时间对水凝胶温度响应速率的影响,并且与传统方法制备的P(NIPAm-co-AAm)水凝胶进行了响应速率对...     

智能纳米水凝胶的应用研究进展

智能纳米水凝胶既有尺寸小、比表面积大的特点,又有生物相容性好、可响应外界刺激发生体积和亲水—疏水性等物理化学性能变化的特性,还有响应速度比智能水凝胶快得多的优点,因此它在许多领域呈现出诱人的应用前景.该篇文章介绍了智能纳米水凝胶在药物输送与可控释放、医学诊断、生物传感器、生物材料、微反应器、催化剂载体、吸附与分离和水处理等方面的应用研究情况.最后对智能纳米水凝胶未来的应用研究前景提出了一些粗浅的看法.     

快速响应型P(NIPA-co-SA)水凝胶制备及温敏性能

研究具有较高LCST且响应速率快的温敏性水凝胶。以NaCl水溶液为反应介质,采用相分离法合成了多孔水凝胶P(NIPA-co-SA)。利用傅立叶变换红外光谱仪(FT-IR)表征产物结构,并借助扫描电子显微镜、差示扫描量热法(DSC)、浊度法等手段研究了反应介质浓度对产物微观形貌、相变温度和相变响应速率的影响规律。结果表明,P(NIPA-co-SA)水凝胶具有对温度敏感的响应特性,其低临界溶解温度(LCST)可达到75℃。NaCl水溶液浓度不影响产物的LCST,且随着反应中NaCl水溶液浓度的提高,水凝胶表面逐渐出现不连续的浅而封闭的小孔到互相贯穿的开孔,水凝胶相变响应速率在一定范围内逐渐提高,具有快速响应特性。     

多孔P(NIPAm-co-AAm)水凝胶对蛋白质控制释放的研究

采用冷冻聚合法制备了多孔结构的P(NIPAm-co-AAm)智能水凝胶,选用牛血清白蛋白(BSA)为模型药物分子,通过后包裹技术负载蛋白质药物,考察了多孔水凝胶中蛋白质药物的载药量和体外释放行为,研究了不同干燥处理方法对载药后水凝胶的药物控释性能的影响,并且与传统方法制备的P(NIPAmco-AAm)水凝胶进行了药物控释性能对比实验。实验结果表明,在凝胶中引入多孔结构使得P(NIPAm-coAAm)水凝胶的药物载药量和释放量得到了显著的提高。不同的干燥处理方法对多孔P(NIPAm-co-AAm)水凝胶的药物释放影响很大,载药后的凝胶采用冰箱冷冻干燥处理,可使蛋白质药物有较好的缓释效果。     

多孔P(NIPAm-co-AAm)水凝胶对蛋白质控制释放的研究

采用冷冻聚合法制备了多孔结构的P(NI-PAm-co-AAm)智能水凝胶,选用牛血清白蛋白(BSA)为模型药物分子,通过后包裹技术负载蛋白质药物,考察了多孔水凝胶中蛋白质药物的载药量和体外释放行为,研究了不同干燥处理方法对载药后水凝胶的药物控释性能的影响,并且与传统方法制备的P(NIPAm-co-AAm)水凝胶进行了药物控释性能对比实验。实验结果表明,在凝胶中引入多孔结构使得P(NIPAm-co-AAm)水凝胶的药物载药量和释放量得到了显著的提高。不同的干燥处理方法对多孔P(NIPAm-co-AAm)水凝胶的药物释放影响很大,载药后的凝胶采用冰箱冷冻干燥处理,可使蛋白质药物有较好的缓释效果。     

N-异丙基丙烯酰胺类纳米水凝胶在生物识别中的研究进展

智能型纳米水凝胶是一种内部为三维网络结构且能稳定分散在水中形成胶体体系,粒径在1～1 000 nm,能感知外界环境刺激,并对其进行响应的新型高分子材料。其中具有温敏性的N-异丙基丙烯酰胺类纳米水凝胶是目前水凝胶研究的热点之一,它会随着外界温度的改变而发生体积相转变,凭借其良好的生物相容性和灵敏的温度响应性,在给药系统、蛋白质分离、医学诊断、生物传感器、生物材料等生物医学领域受到了广泛的关注。结合本课题组近年来的相关工作,主要综述了基于N-异丙基丙烯酰胺类纳米水凝胶微球在蛋白识别、药物输送与释放、DNA分离等生物识别中的应用研究和发展前景。     

孔隙率对多孔聚乙烯醇缩甲醛凝胶性能的影响

通过成孔剂法制备不同孔隙率的聚乙烯醇缩甲醛凝胶(PVFM),其具有对含水量变化快速响应的特性,研究其在吸水、脱水过程中孔隙率对体积、质量、力学性能变化的影响。研究表明,多孔凝胶的孔隙率越高,其吸水、脱水的速度越快。而其力学性能及随含水量变化的敏感性却相应降低。在流量控制、湿度调节等多孔凝胶驱动控制的系统中．缩短凝胶响应时间的同时,要保证其力学行为随含水量变化的敏感性。     

基于酶响应的智能材料研究

酶响应材料是一种新型智能材料,具有广阔的应用前景,因其优异的生物性能受到人们的广泛关注。综述了近年来的酶响应水凝胶材料,总结归纳了酶响应材料的组成、酶的作用方式、材料的响应机理;重点介绍了酶催化下材料的响应,主要包括自组装的形成、破坏,可逆变化。与其他智能材料相比,酶响应材料生物相容性好,降解可控,是未来智能材料的发展方向之一。     

Click synthesis of the thermo- and pH-sensitive hydrogels containing β-cyclodextrins

Novel intelligent hydrogels containing β-cyclodextrins were prepared by tandem physical and chemical crosslinking method based on Diels–Alder reaction. First, dienophile-functionalized cyclodextrins (HCD–AMI) were synthesized by the coupling reaction of hydroxyethyl-β-cyclodextrins and N-maleoyl alanine (AMI); diene-functionalized polymers (PFMIPA) were synthesized by free radical copolymerization of N-isopropylacrylamide and furfuryl amine maleic acid monoamide, a novel monomer synthesized in our lab. Then, the LCSTs of the PFMIPA were estimated by transmittance measurements of copolymer solutions. After the as-synthesized PFMIPA and HCD–AMI were dissolved separately in water and mixed, the hydrogels with physical crosslinks formed quickly within 10 s at 37 °C. Subsequently, chemical crosslinks came into being gradually due to Diels–Alder reaction. Therefore, there are both physical crosslinks and chemical crosslinks in as-prepared hydrogels, resulting in the improvement of the mechanical strength of the hydrogels. And the in vitro degradation behaviors of the resultant hydrogels were given a pilot study. A general gravimetric method was used to study the swelling behavior of the hydrogels. It was found that the hydrogels showed good pH/temperature-sensitivity. The strategy described here has several advantages for preparing intelligent hydrogels including tunable gelation rate, mild reaction conditions, no initiator or catalyzer, and no organic solvent. We believe that this novel, potentially biocompatible hydrogels could have biomedical applications, especially in the area of tissue engineering and drug-controlled release carriers.     

环境敏感性高分子水凝胶

敏感性高分子水凝胶具有对环境的可响应性,该类物质也被称为"智能凝胶"(Intelligent hydrogels)或"灵巧凝胶"(Smart hydrogels)。目前,对敏感性高分子水凝胶的研究已成为智能高分子材料领域的热点之一,综述了环境敏感性高分子水凝胶的种类与性质、主要应用等方面的研究进展。     

PNIPA/PEG多孔智能水凝胶的辐射合成与性能研究

采用辐射法合成了一系列具有合适相变温度和快速响应性能的PNIPA/PEG多孔智能水凝胶,用红外光谱分析了水凝胶的结构,并测定了水凝胶的溶胀动力学、平衡溶胀率和退溶胀动力学,研究了辐射剂量和成孔剂分子量对凝胶性能的影响.结果表明,PEG分子仅在聚合交联过程中充当成孔剂,不参与反应,反应后被除去;PNIPA/PEG水凝胶的平衡溶胀率(SR)随辐射剂量的升高而减小,其最低临界相转变温度(LCST)在37℃左右,且基本不受辐射剂量的影响;溶胀性能随着PEG分子量的增大而提高.     

可生物降解智能水凝胶的研究进展

可生物降解智能水凝胶因其在生物医学领域有着广泛的应用前景，因而已成为科研工作者研究的热点。详细介绍了可生物降解智能水凝胶的研究现状及其在药物释放体系中的应用，并预测了智能水凝胶可能的发展方向。     

Thermoresponsive hydrogel with rapid response dynamics

Intelligent hydrogels, particularly poly(N-isopropylacrylamide) (PNIPAAm)-based hydrogels, have attracted extensive interest because the soft wet hydrogels can change their shapes in response to the small changes of environmental factors like temperature. In order to fully make use of this unique property of PNIPAAm-based hydrogels, the response rates of the PNIPAAm hydrogels have to be improved since the dynamics property is critical to certain applications of this material. In this paper, the thermo-sensitive PNIPAAm hydrogels were successfully synthesized by carrying out the polymerization of N-isopropylacrylamide monomer in vacuum (–100 kPa) at room temperature (22 °C). The resultant hydrogel has tremendously improved shrinking rate as well as the large volume changes upon temperature stimulation when comparing with the normal PNIPAAm hydrogel. The SEM micrographs revealed that the improved properties were attributed to the macroporous network structure generated during the synthesis under vacuum.     

Preparation,properties, and drug release of thermo- and pH-sensitive poly((2-dimethylamino)ethyl methacrylate)/poly(<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-diethylacrylamide) semi-IPN hydrogels

In this paper, a series of semi-interpenetrating polymer network (semi-IPN) hydrogels based on poly((2-dimethylamino)ethyl methacrylate)/poly (N,N-diethylacrylamide) (PDMAEMA/PDEA) were synthesized by changing the initial PDMAEMA/DEA molar ratio at room temperature. The influence of this additive on the property of resulting PDEA hydrogels was investigated and characterized. The interior morphology by scanning electron microscopy (SEM) revealed that the semi-IPN hydrogels have interconnected porous network structures. The glass transition temperature (T _g) of the semi-IPN hydrogels was observed by differential scanning calorimetry (DSC). Equilibrium swelling ratio (ESR), swelling and deswelling dynamics of the hydrogels responding to temperature and pH were investigated in detail. Compared to PDEA, the semi-IPN hydrogels exhibited excellent mutative values in response to an alternation of the temperature and pH, and showed fast swelling and deswelling rates in response to temperature and pH change. The release behaviors of the model drug, aminophylline, were found dependent on hydrogel compositions and environmental temperature. These results suggest that the stimuli semi-IPN hydrogel have potential application as intelligent drug carriers.     

光响应高分子凝胶的研究与进展

光响应高分子凝胶是智能高分子凝胶中的一种,近年来备受世界各国科学家的重视.综述了近年来光响应智能高分子凝胶材料的最新研究进展,具体介绍了光响应高分子凝胶的光响应机理、种类及目前的应用研究状况,并展望了其未来的应用研究与发展.