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阿司匹林壳聚糖纳米缓释微球的制备及体外释放性能的研究 总被引:5,自引:0,他引:5
以自制阿司匹林为药物,壳聚糖为载体,采用乳化-化学交联法制备了阿司匹林-壳聚糖载药微球,确定了阿司匹林-壳聚糖载药微球的制备工艺条件,探讨搅拌速度、阿司匹林/壳聚糖质量比、交联剂戊二醛、乳化剂Span-80用量对微球的药物包封率、载药量和释药性能的影响。研究结果表明,室温条件下,以液体石蜡为介质,选用3%的壳聚糖冰醋酸溶液、按阿司匹林∶壳聚糖=1.5∶1、4%的戊二醛为交联剂、Span-80用量为体积比6%、中等搅拌速度制备出的微球药物包封率可达79%,微球粒径最小可达20 nm,制得的载药微球在16 h内对药物有良好的缓释作用,在25 h之内仍存在缓药效果。 相似文献
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羟丙基壳聚糖微球的制备与性能 总被引:2,自引:1,他引:2
以壳聚糖、环氧丙烷为原料合成羟丙基壳聚糖,以此为壳材,以胰岛素为芯材,制备微球,并考察微球的性能.单凝聚法制备微球.通过IR、XRD和DSC表征微球的化学结构,采用光学显微镜和扫描电镜观察微球的形貌,并考察微球稳定性.搅拌速度为400 r/min、交联荆用量为0.15 mL、HPCS浓度为8%,得到的微球形状规整,包埋率为63%,粒径大小适中,分布范围窄;各种环境下稳定性合适.羟丙基壳聚糖包覆胰岛素微球各种性能研究表明:此载药微球满足药用需要. 相似文献
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以壳聚糖(CS)和海藻酸钠(ALG)为包封材料,以阿维菌素(AVM)为芯材,采用锐孔法制备了阿维菌素-海藻酸钠-壳聚糖微球,考察了海藻酸钠质量分数、壳聚糖质量分数、氯化钙质量分数和芯壁体积比(质量分数1%的阿维菌素乳液与质量分数3%海藻酸钠溶液的体积比)对微球形态及包埋率的影响,利用SEM、FTIR等对微球结构及性质进行了表征,并考察了其在土壤中的缓释性能和释药机制。结果表明,经优化的制备条件为:海藻酸钠、壳聚糖及氯化钙的质量分数分别为3%、0.6%及5%,芯壁体积比为1∶2,制备的载药微球形状规整,成球性良好,粒径约0.7 mm,载药量31.65%,包埋率83.81%;红外光谱分析显示,芯壁材料之间除氢键外,没有发生化学作用。所制备的阿维菌素微球在土壤中具有缓释特性,42 h累积释药率达到82.06%,之后药物释放减缓。药物释放特性符合Riger-Peppas模型,释放机理为Fick扩散。 相似文献
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利用毛细管共挤出技术结合静电吸附和仿生硅化的方法,制备了海藻酸钙-壳聚糖/精蛋白/二氧化硅(ACPSi)复合微胶囊。ACPSi复合微胶囊的平均粒径约3.18 mm,单分散性好,囊壁最外层的二氧化硅层可抑制其在肠液pH环境中的溶胀,增强囊的机械稳定性。将羟丙甲基纤维素邻苯二甲酸酯(HPMCP)肠溶微球作为释药“微阀门”,嵌入囊壁可以更好地控制微胶囊的释药行为。以吲哚美辛为模型药物,当药物浓度为22.5 mg/ml时,ACPSi载药微胶囊在pH 2.5模拟胃液中3 h时累计释药率仅为0.33%,而转移至pH 6.8模拟肠液中19 h时累计释药率为77.78%;囊壁嵌入HPMCP微球后,22 h时累计释药率可提高约4%。因此,该复合微胶囊具有良好的肠靶向作用和控释特性,作为口服肠靶向缓控释制剂具有良好的应用前景。 相似文献
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为了制备具有蛋白药物结肠靶向释放性能的新型药物载体,采用了水相溶液滴定反应法,分别以牛血清白蛋白(BSA)和乳铁蛋白(LF)为模型蛋白质药物,制得壳聚糖/纤维素磷酸钠(NaCS)/三聚磷酸钠(TPP)载药微球。利用电镜SEM和显微镜观测拍照,对微球的表面和截面形貌进行了表征,发现微球球形规则且颗粒大小均一。同时进行了体外药物模拟释放试验,考察了载药微球先后经过模拟胃液、模拟小肠液和模拟结肠液时的释药性能,及不同的释放条件和制造条件对于微球释药性能的影响,尤其考察了不同蛋白药物和不同干燥方式的影响。结果表明由临界点干燥法制得的负载乳铁蛋白(LF)微球在模拟胃液和小肠液释放量中5 h内只释放出不到20%的蛋白药物,而后在结肠模拟液中4 h内释放出蛋白药物80%以上。这些结果表明,壳聚糖/NaCS/TPP体系具有一定的作为结肠靶向药物释放载体的应用潜力。 相似文献
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采用聚(乳酸-羟基乙酸)共聚物(PLGA)纳微球装载紫杉醇,并用壳聚糖季铵盐(HTCC)对PLGA微球表面进行镀层修饰,比较了修饰前后载药微球的形貌、粒径、电位、载药率、释药行为和细胞杀伤效果. 结果表明,修饰后微球表面圆整光滑,平均粒径为882 nm,载药率可达5.15%,包埋率达70.46%,体外释药22 d累积释药率为70.17%,与修饰前没有显著性差异;但修饰后微球表面电荷由修饰前的-14.8 mV翻转为+36.7 mV,肿瘤细胞对PLGA和HTCC-PLGA载药微球的内吞量分别是Taxol?的5.6和9.7倍,且HTCC-PLGA载药微球对细胞杀伤效果显著,是一种有潜力的难溶性药物递送系统. 相似文献
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载胰岛素壳聚糖微球口服降血糖作用的研究 总被引:3,自引:0,他引:3
为了研制一种生物利用度高且具有缓释作用的口服胰岛素制剂,采用静电液滴工艺制备载胰岛素壳聚糖-海藻酸钙微球,以四氧嘧啶为诱导剂建立糖尿病小鼠模型,采用葡萄糖氧化酶法测定小鼠血糖含量,对载药微球的口服药效学进行评价。结果表明:载胰岛素微球平均粒径48μm,药物包封率94.1%,胰岛素相对活性71.7%;药效学研究表明,口服高(4.8 IU/kg)、中(3.6 IU/kg)、低(2.4 IU/kg)3种剂量胰岛素微球,糖尿病小鼠相对血糖值口服6 h时降至最低,分别为42.69%,59.8%,76.13%,药理相对生物利用度为41.20%,37.76%,35.81%。口服载胰岛素壳聚糖-海藻酸钠微球具有降血糖作用和显著的缓释作用,药理相对生物利用度高。 相似文献
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采用溶液浇铸法制备了聚己内酯⁃姜黄素(PCL⁃CUR)多孔支架,通过冷场发射扫描电子显微镜(SEM)和热重分析仪(TG)等对支架材料的孔隙率、载药量及缓释性等进行了表征,并分析了其体外释药模型。结果表明,CUR在支架材料中含量为2 %(质量分数,下同),PCL在醋酸中浓度为10 %,壳聚糖在支架材料中含量为2.86 %时,其释药模型符合1级方程,支架材料的孔隙率达95 %以上,载药量达到1.63 %,在PBS缓冲液中90 h内CUR累计释放率为76.2 %;其他配方的支架材料孔隙率均为95 %以上,90 h内CUR累计缓释率在60 %~87 %之间,表明制得的支架材料具有较理想的孔隙率和明显的CUR药物缓释作用,在组织工程领域有较好的应用前景。 相似文献
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Homogeneous ZnSe hollow microspheres were synthesized on a large scale through an EDTA-assisted mixed solvothermal strategy without any surfactants and templates. The as-synthesized ZnSe microspheres were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and UV–vis absorption spectroscopy. The results of photodegradation of methylene blue (MB) indicate that the hollow microspheres exhibit a visible-light-responsive photocatalytic behavior. As compared with the bulk ZnSe, the photocatalytic efficiency for the hollow microspheres was enhanced remarkably, which might be related with the hollow aggregates of ZnSe nanocrystallites. 相似文献
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Tengfei Fan Jianguo Feng Chao Ma Chi Yu Jing Li Xuemin Wu 《Journal of Porous Materials》2014,21(1):113-119
Porous microspheres with different sizes were prepared through solvent evaporation method with ethylcellulose as a matrix material and abamectin as a core material. The abamectin-loaded microspheres were characterized through scanning electron microscopy (SEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The chemical structure of the microspheres was determined through FTIR. DLS analysis showed that the diameter of the microspheres range from 10 to 100 μm. SEM analysis revealed that the inner structure of the microspheres is characterized by a porous network. TGA revealed that the microspheres are thermally stable below 125 °C. The controlled release of abamectin from the microspheres into water and soil was also investigated. Abamectin was released from microspheres into water through diffusion. The release of abamectin into soil was mainly caused by erosion, a result that was verified through SEM. 相似文献
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Yongjun He 《Powder Technology》2005,155(1):1-4
Nanostructured CeO2 microspheres with an average diameter of 11 μm were prepared by a novel surfactant-free emulsion for the first time. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunauer-Emmet-Teller (BET) measurements were used to characterize the products. The images of SEM showed that the CeO2 microspheres consisted of petal-like nanostructures with petal thickness in a range of 60 nm to 100 nm. The BET measurements showed the specific surface area of the CeO2 microspheres exceeded 43 m2/g. The XRD analysis indicated the nanostructured CeO2 microspheres were of cubic lattice. A possible mechanism of an interfacial precipitation reaction with the droplets of solid-stabilized emulsion as templates was proposed. 相似文献
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Berberine hydrochloride is a natural medicine with wide clinical application. In this article, berberine hydrochloride was entrapped into alginate microspheres via an emulsification/gelation method. The size distribution of the microspheres was determined by a laser particle sizer. Drug distribution within the microspheres was determined by confocal laser scanning microscopy. Those drug‐loaded microspheres were further entrapped into carboxymethyl chitosan (CMC) hydrogel to form a new drug‐delivery system (DDS). The surface morphology of the DDS was observed using metallographic microscopy and scanning electron microscopy (SEM). The compression strength of the DDSs with alginate microspheres was found significantly higher than that of the pure hydrogel. The drug‐release performances of the DDS in phosphate buffer solution (PBS, pH 7.4), saline solution (pH 6.3), and hydrochloric acid solution (HAS, pH 1.2) were also studied. Decay of the DDS in PBS within 72–80 h results in a faster release; however, the steady release in saline solution could last for all the testing period without cleavage of the DDS. In HAS, because of the shrinkage of the DDS, release is fast in the first period and remains steady later. The DDS exhibits prospective in controlled steady release of drugs. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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Edith Mathiowitz Howard Bernstein Steve Giannos Phillip Dor Tom Turek Robert Langer 《应用聚合物科学杂志》1992,45(1):125-134
The morphology of bioerodible polyanhydride microspheres produced by spray drying is described. Microspheres prepared from a variety of homo- and copolymers were studied and characterized using X-ray powder diffraction, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Crystalline polymers, such as poly(sebacic anhydride) (P(SA)) and poly(fumaric acid) (P(FA)), yielded microspheres with a crenelated and porous surface, as judged by SEM. Polymers, with lower crystallinity, such as copolymers of carboxyphenoxypropane and sebacic acid P(CPP-SA), yielded microspheres with a smooth external surface. Polymer crystallinity decreased after spray drying, for both blank and drug loaded microspheres. 相似文献
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Poly(divinylbenzene) (PDVB) hollow microspheres with pyridyl group located on their interior surface were prepared by a facile route with the aid of the vinyl groups on the surface of poly(methacrylic acid) (PMAA) microspheres, which were incorporated through the hydrogen-bonding interaction between the carboxylic acid group and pyridyl group of 4-vinylpyridine (VPy). Poly(methacrylic acid)@polydivinylbenzene (PMAA@PDVB) core-shell structure microspheres with PMAA as core and PDVB as shell were synthesized by a two-stage distillation-precipitation polymerization technique through the capture of the DVB monomer from solution of the reactive vinyl groups on pyridyl-functionalized PMAA microspheres based on a seeded-nucleation mechanism during the second-stage polymerization. The PDVB hollow microspheres with different shell thicknesses were developed after the PMAA core particles were removed by selective dissolution under basic condition in ethanol, during which the pyridyl group was left on the interior surface of the shell layer in PDVB hollow microspheres. The resultant core-shell and hollow microspheres were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), dynamic light scattering (DLS), Fourier transform infrared spectra (FT-IR) and elemental analysis. 相似文献
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Yttrium–aluminum–garnet (YAG, Y3 Al5 O12 ) hollow microspheres were synthesized by reverse-emulsion (w/o) technique starting with aqua-based precursors of oxides. The non-ionic surfactant was used as the emulsifying agent. The gel powders were calcined at 700°–1200°C. The synthesized powders were characterized by differential thermal analysis (DTA), thermogravimetry, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The appearance of an exothermic peak at 932°C in the DTA curve revealed the crystallization of YAG, which was further confirmed by XRD and FTIR studies. SEM confirmed the formation of hollow microspheres. 相似文献
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在液相反应条件下,采用微波加热,在室温离子液体1-甲基-3-丁基咪唑四氟硼酸盐中成功地制备出SnO2微球。采用X射线衍射仪、扫描电子显微镜、透射电子显微镜、N2物理吸附仪、热重分析仪对所制备的样品进行了结构表征。结果表明,制备的SnO2是平均直径为2~3μm的实心小球,具有四方金红石结构且含有介孔孔道结构性质。 相似文献
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采用氨催化水解正硅酸乙酯制备了单分散二氧化硅微球,通过透射电子显微镜观察微球的粒径及其单分散性。利用垂直沉积法制备二氧化硅胶体晶体,通过扫描电子显微镜观察其形貌,利用紫外-可见光分光光度计对其带隙结构进行表征。结合模板技术,采用无皂乳液聚合制得三维有序聚苯乙烯大孔材料,通过扫描电子显微镜观察结构的有序度。结果表明:聚苯乙烯大孔材料结构高度有序,形成开放的三维通道网络,为聚合物大孔材料在诸多领域的潜在应用提供了可能。 相似文献