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51.
Preparation and Characterization of Biodegradable Polylactide(PLA) Microspheres Encapsulating Ginsenoside Rg3 总被引:1,自引:0,他引:1
LIU Cheng-bai ZHANG Di LI De-guan JIANG Dan CHEN Xia 《高等学校化学研究》2008,24(5):588-591
In this study, the process of a biodegradable polylactide(PLA) microsphere encapsulating ginsenoside Rg3 was first studied by the emulsion solvent evaporation method, for enhancing solubility and stability of ginsenoside Rg3. Alabum was also first used as a modifier in this method. The mean diameter of the prepared PLA microspheres containing Rg3 was 40 μm. Ginsenoside Rg3 released from the microspheres was studied by HPLC and detected by UV. It was found that the drug release curve fitted the Model Heller-Baker best. 相似文献
52.
The effect of polylactic acid (PLA), cellulose microfibers (CEL), and calcium carbonate (CaCO3) on the equilibrium moisture content (EMC), density and flexural mechanical properties of starch-based bio-foams was studied using a full factorial design 23. Also, a moisture aging study was carried out. The results show the three factors studied changed the bio-foams morphology, contribute to density increment, enhance dimensional stability and improve both the moisture resistance and the mechanical flexural properties. The moisture aging studies show that, although the flexural mechanical properties decrease with increasing humidity, the bio-foams exceed the mechanical properties of commercial expanded polystyrene (EPS) trays. These findings suggest the bio-composites could be used in regions where the humidity conditions are moderate to very humid, guaranteeing their dimensional stability and functional properties. Thus, these new bio-foams are an attractive and sustainable option to replace the non-biodegradable EPS commercial trays. 相似文献
53.
利用静电纺丝技术制备了一种具有抗菌性能的氧化锌(ZnO)/聚乳酸(PLA)/聚己内酯(PCL)载药微纳米纤维膜,并通过扫描电子显微镜(SEM)、X射线衍射(XRD)和傅里叶变换红外光谱(FTIR)分别对复合膜的表面形态、元素组成和化学结构进行表征。通过抗菌实验评价了复合膜的抗菌性能,用紫外分光光度计测试复合膜在体外的药物释放行为。结果显示,以物理共混的方式将ZnO和氢溴酸高乌甲素(LAH)成功载入复合微纳米纤维;与PLA/PCL复合微纳米纤维膜相比,ZnO/PLA/PCL复合微纳米纤维膜表现出更好的抗菌效率。当ZnO含量为10%(wt)时,复合微纳米纤维膜具有最佳的抗菌性能;药物释放性能结果表明,ZnO/PLA/PCL复合微纳米纤维膜具有良好的药物缓释性能。 相似文献
54.
55.
功能化聚乳酸微球改性聚乳酸膜片表面及其细胞相容性 总被引:3,自引:0,他引:3
以两亲三嵌段共聚物PEO PPO PEO及其氨基酸、多肽RGD衍生物作为微球制备过程中的表面稳定剂 ,低分子量的聚乳酸作为成核材料 ,采用o w乳液溶剂挥发法制备得到表面含不同氨基酸的聚乳酸微球 ,荧光标记手段证明了氨基酸存在于微球的表面 ;利用溶胀嵌入固定法将微球固定到具有生物惰性聚乳酸膜片表面 ,制备得到了具有良好稳定性的微球改性聚乳酸生物惰性膜片 ;成骨细胞相容性测试表明 ,氨基酸尤其是多肽RGD在生物惰性聚乳酸表面的引入能较大程度地提高聚乳酸生物惰性表面的细胞相容性 ,能较好地诱导细胞行为如细胞粘附、增殖等过程的发生 ,为实现对细胞行为的诱导控制提供了一种新途径 . 相似文献
56.
N.S. Oliveira C.M. Gonalves J.A.P. Coutinho A. Ferreira J. Dorgan I.M. Marrucho 《Fluid Phase Equilibria》2006,250(1-2):116-124
The objective of this work is to study the gas/vapor sorption in poly(lactic acid) (PLA) with a 98:2 (l:d) ratio using a quartz crystal microbalance (QCM). For that purpose, the sorption of carbon dioxide, ethylene and water vapor in poly(lactic acid) (PLA) with a 98:2 (l:d) ratio, in temperature range from 283 to 313 K and up to atmospheric pressure was measured. The measured isotherms indicate that the sorption mechanism is sorbate dependent, since carbon dioxide and ethylene seem to have predominantly a Langmuir type of mechanism while water is predominantly Henry controlled. Two temperature protocols were used and only ethylene sorption is affected by them. Comparisons with previously measured gas sorption data in PLA 80:20 using the same temperature protocol indicate that the l:d ratio plays a dominant role in gas/vapor sorption in PLA. 相似文献
57.
Effect of dyeing on melting behavior of poly(lactic acid) fabric 总被引:5,自引:0,他引:5
The effect of the dyeing on the melting behavior of poly(lactic acid) fabrics was investigated by differential scanning calorimeter.
The DSC melting peaks at 10°C min-1 of the untreated poly(lactic acid) fabric were observed at a temperature higher than those of the dyed fabrics. The restricting
force from the extended tie molecules along the fiber axis seems to decrease in the dyeing process. When the sample was rapidly
heated, the crystallites melted at lower temperatures since recrystallization was restricted. It was estimated, based on the
heating-rate dependency of melting behavior, that the original crystallites of the untreated sample melted at 146.1°C and
those of the dyed samples melted at higher temperatures, suggesting that their crystallites are grown to be more perfect in
the dyeing process.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
58.
《Macromolecular bioscience》2018,18(6)
Local application of anticancer agents prolongs the presence time and increases the concentration of drug in the target place and therefore may reduce serious side effects compared to drug systemic administration. The preparation of fibrous materials of polylactide (PLA) and polyethylene glycol (PEG) loaded with paclitaxel (PTX, 1 or 10 wt%) is presented. Scanning electron microscopy proves that PTX is homogeneously incorporated into the fibers. The addition of PEG of various molecular weights (6, 20, or 35 kDa) ensures the release of significantly higher amounts of hydrophobic PTX in a prolonged release time compared to the fibers containing PTX only. Present PLA‐PEG fibrous carriers can serve as a drug depot for PTX since they exhibit significant toxicity for cancer cell lines in several‐day experiment. They are promising for local recurrence therapy, where the initial release is efficient to kill tumor cells and continued release can prevent their subsequent proliferation. 相似文献
59.
Ging‐Ho Hsiue Chun‐Liang Lo Ching‐Hao Cheng Che‐Ping Lin Chun‐Kai Huang Hung‐Hao Chen 《Journal of polymer science. Part A, Polymer chemistry》2007,45(4):688-698
A poly(D,L ‐lactide)–bromine macroinitiator was synthesized for use in the preparation of a novel biocompatible polymer. This amphiphilic diblock copolymer consisted of biodegradable poly(D,L ‐lactide) and 2‐methacryloyloxyethyl phosphorylcholine and was formed by atom transfer radical polymerization. Polymeric nanoparticles were prepared by a dialysis process in a select solvent. The shape and structure of the polymeric nanoparticles were determined by 1H NMR, atomic force microscopy, and ζ‐potential measurements. The results of cytotoxicity tests showed the good cytocompatibility of the lipid‐like diblock copolymer poly(2‐methacryloyloxyethyl phosphorylcholine)‐block‐poly(D,L ‐lactide). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 688–698, 2007 相似文献
60.
HU Yushan BAI Dongren ZHANG Zhengpu WANG Yongmei HE Binglin 《Chinese Journal of Reactive Polymers》1999,(Z1)
1INTRODUCTIONSinceKulk~ietallllshowedthathighmolecularweightpolylactide(PLA)weredegradableinvivoandthusofinterestforbiomedicalapplications,PLAhasbeenstUdiedextensivelywithrespecttopotentialusesinsurgeryandinphannacology['l,suchasbonefractUrefixation,surgicalsut'Ureandcontrolledrelease.BecauseofitSbiocompatibility,itSdegradability,themetabolizationofdegradationbyproductsandthepossibilityofmodificationbytakingadvantageofcopolymerizationandblending,PLAispresentlyconsideredasthemostattra… 相似文献