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为减少泊洛沙姆水凝胶的溶胶-凝胶转变温度对浓度的依赖性,以泊洛沙姆(P407)为基材,将己酰化乙二醇壳聚糖(HGC)与泊洛沙姆复合,制备了己酰化乙二醇壳聚糖/泊洛沙姆(HGC/P407)复合水凝胶,利用FTIR、SEM及试管反转法探讨了HGC/P407复合水凝胶的性能,并利用紫外-可见分光光度计(UV-vis)对HGC/P407复合水凝胶的体外药物缓释性能进行表征。结果表明,通过控制HGC的加入量,基于3%泊洛沙姆的HGC/P407复合水凝胶即可发生溶胶-凝胶转变现象,并使HGC/P407复合水凝胶的溶胶-凝胶转变温度处于32~37℃。HGC/P407复合水凝胶具有高度孔隙率,孔隙之间相互连通,孔径大小处于10~90μm的范围之内。HGC/P407复合水凝胶对抗癌药物吉西他滨的释药量达到82.4%~90.6%,缓释时间可达80 h左右。HGC/P407复合水凝胶在可注射药物载体领域具有重要的应用前景。 相似文献
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在壳聚糖存在下采用NaBH4还原AgNO3制备了壳聚糖/银纳米复合物。壳聚糖/银纳米复合物的透射电镜(TEM)照片和紫外-可见光谱揭示了银纳米颗粒的存在。此外,研究了氯离子对纳米银光学性质的影响。结果表明氯离子可以加速银纳米颗粒的团聚,紫外-可见光谱表明纳米银的吸收带发生红移并且在高波长段出现一个新峰,暗示纳米银在壳聚糖上可以生长和团聚。 相似文献
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通过一锅合成法制备了CMK-8粉末,将其与适量的壳聚糖和聚乙烯醇复合制备了壳聚糖/聚乙烯醇/CMK-8复合水凝胶。对其进行扫描电镜(SEM)表征并考察了温度、pH、水凝胶量等因素对该复合水凝胶对双酚A的吸附影响。结果表明:该复合水凝胶表面光滑,内部具有紧密的网络结构,对双酚A具有较大的吸附量。在35.0℃、pH为8.0、水凝胶量为1.0g/L时,该复合水凝胶对双酚A的吸附量达到最大,最大吸附量可以达到75.7mg/g。该复合水凝胶的制作工艺较简单且对双酚A吸附量也很可观,为复合水凝胶在污染物吸附的应用提供了重要的参考价值。 相似文献
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泊洛沙姆(poloxamer)是一种温敏性聚合物,在浓度为15.0%(质量分数,下同)~30.0%时可形成凝胶。为改善泊洛沙姆在体温下的成胶浓度和药物缓释性能,以泊洛沙姆407为基底,与新型温敏性乙酰化乙二醇壳聚糖复合,制得了温敏性乙酰化乙二醇壳聚糖/泊洛沙姆复合水凝胶。通过傅里叶变换红外光谱(FT-IR)、试管倒置法、旋转流变仪、扫描电子显微镜(SEM)和紫外-可见分光光度计(UV-vis)对乙酰化乙二醇壳聚糖/泊洛沙姆的结构、温敏性、力学性能、微观形貌和体外药物释放性能进行表征。结果表明,乙酰化乙二醇壳聚糖/泊洛沙姆溶液具有热可逆温敏性溶胶-凝胶转变行为。通过控制乙酰化乙二醇壳聚糖/泊洛沙姆的质量比,能够使溶胶-凝胶转变温度处于室温与体温(25~37℃)之间,缩短凝胶化时间(382s),降低泊洛沙姆407在体温下的成胶浓度(6%)。乙酰化乙二醇壳聚糖/泊洛沙姆复合水凝胶具有高度孔隙化的三维结构,其孔径大小处于10~60μm范围内,且表现出较高的力学性能。乙酰化乙二醇壳聚糖/泊洛沙姆复合水凝胶对抗癌药物吉西他滨具有缓释作用,载药凝胶的释药时间可达72 h。乙酰化乙二醇壳聚糖/泊洛沙姆复合水凝胶在可注射药物缓释载体方面具有重要的应用前景。 相似文献
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采用聚乙烯醇为基础材料,以季铵盐壳聚糖为抗菌剂,丙三醇为辅料,采用溶液共混法制备聚乙烯醇/季铵盐壳聚糖复合水凝胶作为皮肤烫伤敷料,通过流变实验、抗菌实验、细胞实验以及动物活体实验考察复合水凝胶的综合性能。结果表明,制备的复合水凝胶具有适宜的粘度(22~35Pa·s),涂覆于皮肤表面呈现较好的粘附性能;对大肠杆菌和金黄色葡萄球菌均有良好的抑菌作用,同时具有优良的细胞相容性;复合水凝胶敷料对皮肤刺激极小,昆明鼠深Ⅱ度烫伤修复实验表明,凝胶敷料可有效加快创面愈合速度以及瘢痕的形成,创面愈合从一般的数周缩减至3周左右,大大缩短创面修复时间,且愈后瘢痕组织小。 相似文献
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PVA/HA复合水凝胶的结构和摩擦学性能 总被引:3,自引:0,他引:3
将聚乙烯醇(PVA)和纳米羟基磷灰石(HA)按一定比例共混,采用反复冷冻-融化法制备出PVA/HA复合水凝胶.观察了PVA/HA复合水凝胶的微观结构和晶态结构,并在小牛血清稀释液润滑条件下进行了PVA/HA复合水凝胶与牛膝关节软骨的摩擦磨损试验.结果表明:随着冷冻-融化循环数的增加,PVA/HA复合水凝胶结构中氢键的作用增强,缠结结构链上的交联点增多,复合水凝胶的结晶度也随之提高,微孔结构趋于完整,因而使其压缩刚度增大;PVA/HA复合水凝胶与牛膝关节软骨的摩擦系数、接触变形和磨损量都随着冷冻-融化循环数的增加而显著减小,使复合水凝胶的减摩性和耐磨性提高. 相似文献
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Fabrication of chitosan/poly(ε-caprolactone) composite hydrogels for tissue engineering applications
Zhong X Ji C Chan AK Kazarian SG Ruys A Dehghani F 《Journal of materials science. Materials in medicine》2011,22(2):279-288
The aim of this study was to fabricate three-dimensional (3D) porous chitosan/poly(ε-caprolactone) (PCL) hydrogels with improved
mechanical properties for tissue engineering applications. A modified emulsion lyophilisation technique was developed to produce
3D chitosan/PCL hydrogels. The addition of 25 and 50 wt% of PCL into chitosan substantially enhanced the compressive strength
of composite hydrogel 160 and 290%, respectively, compared to pure chitosan hydrogel. The result of ATR–FTIR imaging corroborated
that PCL and chitosan were well mixed and physically co-existed in the composite structures. The composite hydrogels were
constructed of homogenous structure with average pore size of 59.7 ± 14 μm and finer pores with average size of 4.4 ± 2 μm
on the wall of these larger pores. The SEM and confocal laser scanning microscopy images confirmed that fibroblast cells were
attached and proliferated on the 3D structure of these composite hydrogels. The composite hydrogels acquired in this study
possessed homogeneous porous structure with improved mechanical strength and integrity. They may have a high potential for
the production of 3D hydrogels for tissue engineering applications. 相似文献
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磁性羧甲基化壳聚糖纳米粒子的制备与表征 总被引:1,自引:1,他引:0
以化学共沉淀法制备了Fe3O4纳米粒子,壳聚糖经羧甲基化改性后接枝在Fe3O4颗粒表面,得到了磁性羧甲基化壳聚糖(Fe3O4/CMC)纳米粒子.利用透射电镜(TEM)、X射线衍射(XRD)、傅立叶红外光谱(FT-IR)及磁性测试对产物进行了表征.TEM表明Fe3O4纳米粒子被CMC包覆,粒径约10 nm;XRD分析表明复合纳米粒子中磁性物质为Fe3O4;FT-IR表明壳聚糖发生羧甲基反应以及在Fe3O4表面的接枝反应.Fe3O4/CMC纳米粒子具有超顺磁性,比饱和磁化强度25.73 emu/g,有良好的磁稳定性. 相似文献
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壳聚糖经羧甲基化改性后得到水溶性较高的羧甲基壳聚糖(OCMC),它具有优良的稳定性和抗菌性。对比OCMC在不同溶剂中的溶解度,发现OCMC在2wt%乙酸溶液中的溶解性最好。将OCMC与纳米Ag(AgNPs)复合得到Ag-OCMC复合微粒,采用UV-Vis、FTIR、XPS、TEM、SEM和TG-DTA对Ag-OCMC复合微粒的组成、微观结构和热性能进行表征。以大肠杆菌和金黄色葡萄球菌为模型菌种测试Ag-OCMC复合微粒对革兰氏菌的抗菌性能。结果表明:AgNPs为面心立方晶型,平均粒径为40~50 nm;AgNPs的引入提高了壳聚糖和OCMC的分解温度。Ag-OCMC复合微粒对革兰氏菌的抑菌活性明显高于单一壳聚糖基抗菌剂。 相似文献
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Preparation and characterization of macroporous chitosan/wollastonite composite scaffolds for tissue engineering 总被引:2,自引:0,他引:2
Chitosan/wollastonite composite scaffolds were prepared by a thermally induced phase separation method. The microstructure, mechanical performance and in vitro bioactivity of the composite scaffolds were investigated. The composite scaffolds were macroporous and wollastonite particles were dispersed uniformly on the surface of the pore walls. Scanning electron microscope images of the composite scaffolds demonstrated that the scaffolds had interconnected pores with diameters from 60 to 200 microm. Both the pore size and structure were affected by freezing temperature. The mechanical performance of the composite scaffolds was improved compared to that of pure chitosan scaffolds. The in vitro bioactivity of the scaffolds was evaluated by soaking samples in simulated body fluid and the apatite layer was observed on the surface of the pore walls of the composite scaffolds. Our results suggest that the incorporation of wollastonite into chitosan could enhance both the mechanical strength and the in vitro bioactivity of the resultant composite. The macroporous chitosan/wollastonite scaffolds may be a potential candidate for application in tissue engineering. 相似文献
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选用液相化学还原法,分别在以羧甲基纤维素钠(Carboxymethyl cellulose sodium,CMC)和葡萄糖为还原剂的体系下制备纳米银颗粒,并进行了对比分析。通过紫外分光光度计、X射线衍射和透射电镜等测试手段对其进行了表征。结果表明,用CMC体系制备的纳米银粉末平均粒径为20~30nm,为多晶结构;用葡萄糖体系制备的纳米银粉末平均粒径为25~35nm,为面心结构。利用抑菌圈法对纳米银的抗菌性能进行测试,结果显示2种体系下制备的纳米银对海洋芽孢杆菌都有很好的抑制作用。 相似文献