共查询到19条相似文献,搜索用时 125 毫秒
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应用SDS梯度聚丙烯酸胶凝胶电泳法、淋巴细胞增殖法和显微血凝法对三批提纯人IL-2样品中的残留PHA作了检测·结果表明我们提纯工艺对去除PHA效果较好,PHA残留浓度低于25μg/ml,PHA总量从提纯前的600mg降为0.75mg以下.去除率达99%以上,另外,我们还对三种检测方法进行了比较,认为显微血凝法是一种简便、特异、灵敏的方法。 相似文献
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聚羟基脂肪酸酯的合成和应用研究进展 总被引:2,自引:0,他引:2
介绍了聚羟基脂肪酸酯(PHA)的合成方法,重点讨论了微生物合成法、碳源、化学合成、分离方法及降低PHA生产成本的方法,介绍了PHA的性能及其改性研究,论述了PHA在生物医学、农业、电子、食品包装等领域的应用。 相似文献
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聚羟基脂肪酸酯(PHA)具有优异的力学性能、生物相容性和阻隔性能,作为一种生物降解高分子材料在包装材料、组织工程和电学等领域得到广泛应用。结晶速率慢和韧性差限制了PHA应用领域的拓展。通过熔融混合的方法制备了一系列不同聚碳酸丁二酯(PBC)含量的PHA聚合物合金。采用差示扫描量热仪、热重分析仪、万能试验机、扫描电子显微镜和接触角测量仪等表征手段重点考察了PBC含量对PHA/PBC合金结晶、热分解、力学和亲疏水等性能的影响。结果表明,PBC的加入可以提高PHA/PBC合金的结晶峰温度,少量PBC均匀分散在PHA基体中可为成核中心,PBC质量分数为10%的PHA/PBC合金具有最高的结晶度。随着PBC含量的增加,PHA/PBC合金由脆性断裂向韧性断裂转变,PBC质量分数为90%的PHA/PBC合金的断裂伸长率分别是PHA和PBC的143倍和1.6倍,主要因为三柠檬酸三丁酯(TBC)对合金的增塑作用。另外,通过改变PBC含量还可以调控PHA/PBC合金热稳定性和亲疏水性。 相似文献
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《应用化工》2022,(4):1011-1018
采用不同的技术来进行甲烷减量成为当前全球的研究热点。甲烷可以作为电子供体被甲烷氧化菌利用,且在营养限制的条件下合成聚羟基脂肪酸酯(PHA)。利用甲烷氧化菌将甲烷转化为PHA,既可以增加污水中资源的回收,又有助于缓解气候变化问题。大量研究者对纯种甲烷氧化菌进行了研究,证明了其具有PHA积累的能力。然而,工艺参数的优化、反应器的设计、合成PHA的种类单一等问题仍限制着利用甲烷合成PHA。就PHA的性质及应用展开阐述,综述了关于甲烷氧化菌合成PHA的生物代谢途径的研究,并强调了不同环境因素对甲烷氧化菌利用甲烷合成PHA的影响以及未来研究的重点。 相似文献
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通过熔融共混的方法分别制备了聚氯乙烯/邻苯二甲酸二辛酯/聚羟基烷酸酯(PVC/DOP/PHA)和PVC/PHA共混物。研究了PHA逐步代替DOP对共混物力学性能和熔体流动性能的影响规律,利用扫描电子显微镜对所制备的试样进行微观结构分析。结果表明,随着共混体系中PHA用量的增加和DOP的等量减少,与PVC/DOP共混物相比,PVC/DOP/PHA共混物的拉伸强度由21 MPa提高至42 MPa,断裂伸长率先增加而后降低,在PHA含量为10.7 %(质量分数,下同)时出现极大值(350 %);在PVC/PHA体系中,PHA含量增加,PVC/PHA共混物的力学性能及熔体流动速率都显著提高,说明PHA可以作为PVC的一种有效的绿色增塑剂和增韧剂。 相似文献
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聚羟基脂肪酸酯(PHA)具有可生物降解性和生物相容性,是潜在的医学材料。对聚羟基脂肪酸酯进行改性,可提高其应用范围.采用以苯戊酸和蔗糖为混合碳源培养基培养Pseudomonas putida KT2442,对其细胞内合成的聚羟基脂肪酸酯进行生物改性,并利用核磁共振、红外色谱和气相色谱分析方法表征了改性的PHA分子结构。结果表明合成的聚羟基脂肪酸酯为含有3-羟基苯戊酸单体的中长链聚羟基脂肪酸酯(PHPhA),该单体在PHA链中含量为1.04%,为进一步的研究打下基础。 相似文献
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介绍了超细滑石粉在一种可降解塑料聚羟基烷酸酯(PHA)/聚乳酸(PLA)合金材料中的应用情况。滑石粉加入量在合金材料的12%以下时,在添加量为8%时,合金的冲击强度有所降低。同时它能起成核作用,能有效地提高合金材料的结晶速率。对PHA/PLA合金的一些性能,如成型收缩率、力学性能、热变形温度及加工工艺均有明显的改善。 相似文献
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PHA具有很好的生物降解性能,随着聚羟基脂肪酸酯(PHA)的研究及发展,新一代全生物降解塑料聚3-羟基丁酸酯4-羟基丁酸酯(P3HB4HB)是一种综合性能优异的生物塑料,力学性能与通用塑料PP和PE相近,并可以在传统塑料加工设备上加工成型,新一代生物塑料问世较晚,相应的开发研究和应用还需进一步挖掘。 相似文献
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介绍了2种主要的可生物降解聚酯PBS和PHA的原料、生产、性能及应用。指出生物降解聚酯的应用瓶颈正在打破,从可再生资源生产聚合物的技术进步将使全球生物聚酯应用不断升温。 相似文献
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新型生物材料多聚羟基烷酸的开发与应用 总被引:4,自引:0,他引:4
综述了新型生物材料多聚羟基烷酸开发研究的历史与现状,重点介绍了多聚羟基烷酸生产和应用中取得的成果与存在的问题,并展望了这一新材料的发展趋势与应用前景。 相似文献
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Nootchanartch Panith Apinya Assavanig Sittiwat Lertsiri Magnus Bergkvist Rudee Surarit Nuttawee Niamsiri 《应用聚合物科学杂志》2016,133(42)
This article was aimed at preparation and characterization of drug delivery carriers made from biodegradable polyhydroxyalkanoates (PHAs) for slow release of tetracycline (TC) for periodontal treatment. Four PHA variants; polyhydroxybutyrate (PHB), poly(hydroxybutyrate‐co‐hydroxyvalerate) with 5, 12, and 50% hydroxyvalerate were used to formulate TC‐loaded PHA microspheres by double emulsion‐solvent evaporation method. We also compared the effect of different molecular weight (Mw) of polyvinyl alcohol (PVA) acting as surface stabilizer on particle size, drug loading, encapsulation efficiency, and drug release profile. The TC‐loaded PHA microspheres exhibited microscale and nanoscale spherical morphology under scanning electron microscopy. Among formulations, TC‐loaded PHB:low Mw PVA demonstrated the highest TC loading with slow release behavior. Our results showed that the release rate from PHA microspheres was influenced by both the type of PHA and Mw of PVA stabilizer. Lastly, TC‐loaded PHB microspheres showed efficient killing activity against periodontitis‐causing bacteria, suggesting its potential application for treating periodontal disease. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44128. 相似文献
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Cardiovascular diseases are a leading cause of mortality in the world today. Vascular tissue engineering is an important and attractive research issue for the repair and regeneration of blood vessels. Two bio-based polymers, poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), which both belong to the polyhydroxyalkanoate (PHA) family, were used in this study. The aim of this study is to assess the potential application of PHB and PHBV to serve as a scaffold that is seeded with human umbilical vein endothelial cells (HUVECs) or endothelial progenitor cells (EPCs) for vascular tissue engineering. PHA films with various surface characteristics were prepared by solution-casting (surface roughness) and electrospinning (mesh-like structure). First, the mechanical and physical properties of various types of PHA films were analyzed. Then, the PHAs films were examined for cytotoxicity, biocompatibility and proliferation ability using cell lines (3 T3 and L929) and primary cells (HUVECs and EPCs). The cell morphology cultured on the PHA films was observed by fluorescence microscope and scanning electron microscopy. In addition, cultured EPCs on various types of PHA films were analyzed for whether the cells maintained the abilities of Ac-LDL uptake and UEA-1 lectin binding and exhibited specific gene expressions, including VEGFR-2, vWF, CD31, CD34 and CD133. Importantly, the cell retention rate and anti-coagulation ability of HUVECs or EPCs cultured on the various types of PHA films were also evaluated at the indicated time points. Our results showed that PHA films that were prepared using electrospinning methods (Ele-PHB and Ele-PHBV) had good mechanical and physical properties. HUVECs and EPCs can attach and grow on Ele-PHB and Ele-PHBV films without showing cytotoxicity. After a one-week culture, expanded HUVECs or EPCs maintained the correct cell morphologies and exhibited correct cell functions, such as high cell attachment rate and anti-coagulation ability. Taken together, Ele-PHB and Ele-PHBV films were ideal bio-based polymers to combine with HUVECs or EPCs for vascular tissue engineering. 相似文献