肝素化胶原/丝素共混膜的制备及其抗凝血性能

将肝素化胶原与丝素溶液共混,制备了肝素化胶原/丝素共混膜,并采用戊二醛作为交联剂,以提高共混膜的机械性能.共混物的体外抗凝血活性采用部分凝血活酶时间(APTT)、凝血活酶时间(PT)、凝血酶时间(TT)来评价.当戊二醛的质量浓度为5g/L时,肝素的结合率为56%,共混膜的断裂强度为45MPa.APTT、TT、PT凝血时间实验证明,共混膜的APTT、TT、PT分别超过150、200和50s.     

丝素改性胶原膜的低温等离子体改性及体外抗凝血性研究

选用SO2、NH3、CO2三种工作气体，采用低温等离子体技术对丝素改性胶原膜进行了表面改性。运用X光电子能谱分析了材料的表面性质。材料的体外抗凝血性能由体外凝血时间——凝血酶原时间(PT)、部分凝血活酶时间(APTT)、凝血酶时间(TT)作为评价标准。结果表明，SO2、CO2等离子体处理可分别在材料表面引入磺酸和酸酸基团，材料的体外抗凝血性得到很大的改善。NH3等离子体处理可以增加材料表面的氨基的数目，它对材料的抗凝血性没有贡献。     

丝素蛋白膜上vWf抗体的固定化及其体外抗凝血性能

用凝血因子的抗体对生物材料进行表面改性以提高其抗凝血性能。以丝素蛋白膜为基质，利用等离子体处理辅助的共价交联方法对vWf因子（von Wilebrand factor)抗体进行了固定化。用酶联免疫法和抗体过剩法对固定化效果进行了评价，固定化抗体的活性采用体外凝血时间（APPT，TT和PT）测定进行检测。结果显示，通过这种方法可以有效地将vWf抗体固定化，丝素蛋白膜固定化vWf抗体后，其抗凝血性能有了一定的改善。本研究结果拓宽了抗体固定化技术的应用范围，同时为抗凝血材料的设计提供了一种新的思路。     

抗凝血丝素蛋白材料的研究进展

综述了作为抗凝血材料的丝素蛋白的改性方法,重点讨论了用s-羧甲基还原角蛋白、硫酸、二氧化硫和vWf(Von Willebrand fator)因子的抗体等对丝素蛋白的改性,并分析了改性材料的抗凝血机理和抗凝血性能.     

利用胶原-肝素自组装多层膜改善纯钛表面血液相容性的研究

为了改善钛表面的血液相容?用层层自组装技术将抗凝药物肝素和细胞外基质成分之一的胶原层层交替吸附到钛表面,形成多层薄膜,使具有良好的抗凝血功能.钛通过氢氧化钠处理表面带负电,在聚赖氨酸溶液中会吸附一层带正电的聚赖氨酸,然后将其交替浸泡于带负电的肝素和带正电的胶原中形成自组装薄膜.通过傅立叶红外漫反射(FTIR)检测材料表面基团的变化,通过测水接触角的方法跟踪组装过程,通过扫描电子显微镜(SEM)观察材料表面形貌的变化.血小板黏附实验显示钛改性后表面血小板黏附量明显减少,且反映血小板激活程度的P-selectin的表达量结果也显示,钛改性后表面血小板激活程度显著降低,活化部分凝血活酶时间(APTT)和外源性凝血系统的凝血酶原时间(PT)的实验显示钛改性后表面凝血时间延长,血液相容性得到改善.研究说明这种方法对于心血管材料钛的改性有重要价值.     

丝素抗凝血材料的研究进展

综述了丝素材料在抗凝血方面的研究进展,主要从材料表面肝素化、硫酸化、低温等离子体接枝改性、材料表面内皮化或者几种方法协同作用等展开,对比评述了其优缺点,阐述了对丝素材料表面进行抗凝血改性的研究进展.     

肝素化聚醚砜抗凝血材料的研究

进行了聚醚砜表面共价键合肝素的研究,定性定量检测了改性材料中的肝素,并探讨其力学性能和体外凝血时间,结果表明:肝素共价键合到了聚醚砜表面,表面肝素化改性后的聚醚砜材料基本保持了聚醚砜的力学性能,同时抗凝血性能大大提高。     

全身肝素化聚醚砜抗凝血生物材料的研究

对聚醚砜材料进行了全面共价键合肝素的研究,并以表面肝素化聚醚砜材料对照,定性定量检测了改性后新材料中的肝素,并探讨其力学性能和体外凝血时间,结果表明:肝素与聚醚砜以共价键结合在一起,全身肝素化改性后的聚醚砜材料基本保持了聚醚砜的力学性能,同时抗凝血性能大大提高,更适用于医疗器械领域,特别是微型化医疗器械领域.     

丝素蛋白膜表面的等离子体磺酸化及体外抗凝血性能

从蚕丝中提取的丝素蛋白（Silk fibroin）制备成薄膜,首次采用二氧化硫等离子体处理在材料表现引入了磺酸基因;同时丝素蛋白膜用氨气等离子体处理后在表面接入氨基,利用1,3－丙磺酸内酯与氨基的反应在材料表面接枝磺酸。采用X光电子能谱和全反射红光谱分析材料的表面性质。材料的体外抗弟血性能由外凝血时间;凝血酶原时间（PT）、部分凝血活酶时间（APTT）和凝血酶时间（TT）作为评价标准。结果表明两种处理方法均能在丝素蛋白膜表面有效地接枝磺酸基因,而且材料的抗凝血性能有显著提高。     

血液接触高分子膜材料的“类肝素”改性

改善血液接触高分子膜材料的抗凝血性能是当前非常受重视的热点问题。在当前众多的抗凝血高分子膜材料的研究中,笔者课题组通过模拟肝素官能团结构而提出的"类肝素"改性是一种简便高效的方法。文中对接触血液的高分子膜材料的"肝素化"和"类肝素"改性进行了简要的综述。     

Improvements of anticoagulant activities of silk fibroin films with fucoidan

Fucoidan (FC), an effective anticoagulant constituent extracted from brown algae, was introduced into silk fibroin (SF) for improving its blood compatibility. The SF and SF/FC blend films were characterized by attenuated total reflectance Fourier-transform infrared (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and dynamic contact angle determinator (CA). The in vitro anticoagulant activities of the films were evaluated by activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT) measurements. The endothelial cell attachment and proliferation viability on the film were assessed by micropipette aspiration technique and MTT assay, respectively. The testing results indicated that the introduction of FC increased the roughness, hydrophilicity and sulfate component of the film surface without impeding the formation of ?-sheet conformation in SF. More important, FC brought excellent anticoagulant activity and better endothelial cell affinity to SF. The SF/FC blend film was hopeful to be used as blood-contacting biomaterials.     

Improvements of anticoagulant activities of silk fibroin films with fucoidan

Fucoidan (FC), an effective anticoagulant constituent extracted from brown algae, was introduced into silk fibroin (SF) for improving its blood compatibility. The SF and SF/FC blend films were characterized by attenuated total reflectance Fourier-transform infrared (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and dynamic contact angle determinator (CA). The in vitro anticoagulant activities of the films were evaluated by activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT) measurements. The endothelial cell attachment and proliferation viability on the film were assessed by micropipette aspiration technique and MTT assay, respectively. The testing results indicated that the introduction of FC increased the roughness, hydrophilicity and sulfate component of the film surface without impeding the formation of β-sheet conformation in SF. More important, FC brought excellent anticoagulant activity and better endothelial cell affinity to SF. The SF/FC blend film was hopeful to be used as blood-contacting biomaterials.     

氟树脂改性漆酚复合涂料的老化性能研究

采用氟树脂对漆酚进行改性,对改性后漆酚涂膜进行了自然老化和人工加速老化测试。通过傅立叶红外光谱(FTIR)、紫外光谱(UV)及扫描电镜(SEM)等手段对老化后的样品进行表征。结果表明,氟树脂含量在30%～90%(wt)时改性样品经过人工加速老化试验后表面出现破坏的时间大于漆酚涂膜,且经模拟太阳光照射120h后,失光率较小;暴露在自然环境中2880h后,表面仍未出现破坏现象。而漆酚涂膜在自然环境中暴露2544h后,表面已被破坏。研究表明,改性漆酚涂膜的耐老化性能较漆酚涂膜有大幅提高。     

聚乳酸/茶多酚抗氧化膜的制备及其性能研究

以聚乳酸（PLA）为基材,茶多酚（TP）为抗氧化剂,通过流延法制备了具抗氧化活性的可降解PLA/TP共混膜,并研究了茶多酚添加量对共混膜包装性能及抗氧化性能的影响。研究结果表明：茶多酚与聚乳酸基质间发生了相互作用,茶多酚在聚乳酸基质中具有较好的分散性。天然抗氧化物茶多酚的添加使共混膜的拉伸强度、断裂伸长率以及透光率降低,但显著提高了共混膜的热封强度、透湿系数、透氧系数、溶解度和自由基清除率。当茶多酚的质量分数为0.9%时,共混膜的热封强度为3.31 N/(15 mm),透湿系数和透氧系数分别是纯PLA膜的1.68倍和6倍,透光率为88.1%,自由基清除率为89.18%,是一种具有应用潜力的环境友好型食品活性包装材料。     

环化SBS吸氧共混物的制备及其性能研究

目的 制备环化SBS吸氧共混物并对其性能进行研究。方法 以苯乙烯-丁二烯共聚物（SBS）为原料, 在对甲苯磺酸的催化作用下, 制备苯乙烯-丁二烯共聚物环化物 （环化SBS）。将环化SBS与引发剂、 过渡金属催化剂共混制备环化SBS吸氧共混物, 经紫外光照射引发吸氧反应从而吸收氧气。研究环化SBS吸氧共混物的吸氧性能, 以及吸氧反应对吸氧共混物结构与性能的影响。结果 吸氧共混物的吸氧量在第4天时就达到30.7 mL/g, 随着时间的延长, 吸氧量继续增加, 在第10天时基本达到平衡,最大吸氧量为40.2 mL/g。环化SBS经紫外光照射引发吸氧后生成醇类物质, 吸氧后环化SBS吸氧共混物的拉伸强度与断裂伸长率均略有降低, 但是变化不显著。结论 试验制备的环化SBS吸氧共混物具有良好的吸氧性能, 可用于制备单层/多层吸氧薄膜。     

Evaluation of two polymeric blends (EVA/PLA and EVA/PEG) as coating film materials for paclitaxel-eluting stent application

The ethylene vinyl acetate copolymer (EVA)/Poly (lactic acid) (PLA) blend and EVA/Poly (ethylene glycol) (PEG) blend were applied as the drug carrier materials for a bi-layer drug-loaded stent coating film, which consisted of a paclitaxel (PTX)-loaded layer and a drug-free EVA layer. The changes of weight and appearance of the drug-free polymeric blend films with increasing time were examined by X-ray diffraction analysis (XRD), gel permeation chromatography (GPC) tests and scanning electronic microscopy (SEM), and the results showed the degradation of PLA and the leaching of PEG from the films. The effects of PLA, PEG and drug contents on in vitro drug release were investigated, and the results demonstrated that the addition of PLA promoted the drug release while the addition of PEG almost did not. Franz cells diffusion test results indicated that the bi-layer structure successfully endowed the stent coating with the release of drug in a unidirectional fashion. The release profiles of films incorporated PTX and the mechanical performance of the film could be customized by readily adjusting the contents of the blend components. Therefore, the polymeric blends could be useful drug carrier materials for drug-loaded stent coating capable of releasing drug in a highly tunable manner.     

Study on poly(vinyl alcohol)/carboxymethyl-chitosan blend film as local drug delivery system

The distinguishable films composed of poly(vinyl alcohol) (PVA) and carboxymethyl-chitosan (CMCS) were prepared by blending/casting method, and loaded with ornidazole (OD) as local drug delivery system. In vitro test, the blend films showed pH-responsive swelling behavior and moderate drug release action, and also exhibited a little antimicrobial activity against E. coli and S. aureus strains. Those characteristics of CMCS/PVA blend films were essentially governed by the weight ratio of CMCS and PVA. Increasing the content of PVA in blend film would decrease swelling and decelerated the drug release. However, increasing the content of CMCS would enhance the antimicrobial activity. The biocompatibility and bioactivity of the blend film were also evaluated using rabbit blood and Wister rats. This blend drug system was of no hemolysis, no toxicity to rat periodontia and no cytotoxicity to the rat muscle. After subcutaneously implanting the blend drug films in Wister rat, the systems kept a good retention at the application site and maintained high drug concentration in long time (5 days) which was longer than the period of drug released in vitro (160 min).     

聚乙烯/硅橡胶共混膜的制备及其透气性能

为了提高聚乙烯薄膜的透气性能,采用挤出吹塑的方法制备了硅橡胶（聚二甲基硅氧烷,PDMS）含量为1%~5%的聚乙烯（PE）/硅橡胶共混薄膜,用扫描电镜研究了硅橡胶在聚乙烯中的分布,测试了共混膜的透气性能。结果表明,由于吹膜过程中的拉伸作用,硅橡胶颗粒呈细长型分布于聚乙烯基体中,硅橡胶的加入并不能明显改善聚乙烯的透气性能。...     

HECS-g-PDLLA共聚物的微波合成及与聚乳酸的相容性

在微波作用下,以辛酸亚锡为催化剂,羟乙基壳聚糖（HECS）为大分子引发剂引发D,L-丙交酯（D,L-LA）开环聚合制备羟乙基壳聚糖-g-聚乳酸（HECS-g-PDLLA）,通过红外（IR）、元素分析（EA）、氢核磁共振（1H-NMR）、X射线衍射（XRD）和差示扫描量热分析（DSC）对产物进行了表征。然后采用溶液共混法...