共查询到18条相似文献,搜索用时 78 毫秒
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氨甲喋呤(MTX)脂质体的制备及其稳定性 总被引:1,自引:0,他引:1
本文探讨了提高MTX脂质体包裹率、影响它对热稳定性的因素,并自行设计了简便、迅速、重现性好的测定MTX脂质体的方法。结果表明:采用二次乳化蒸发法制备MTX脂质体,在控制乳化温度及有机相比例的条件下,可获得50%左右较高的包裹率。另外提示,脂质体分散溶媒的离子强度和脂质体中胆固醇的含量是影响MTX脂质体对热稳定性的重要因素。以选用50mM的磷酸盐缓冲液为分散溶媒和PC/CHOL/SA的脂质体组成,则100℃加热30分钟灭菌,所包MTX可滞留90%。且灭菌前后的脂质体经电镜观察形态无明显变化。 相似文献
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卵磷脂质量对甲氨喋呤(MTX)脂质体包裹率的影响 总被引:2,自引:0,他引:2
本文研究了卵磷脂的理化性质与MTX脂质体包裹率的关系。分别测定了两种卵磷脂(大豆卵磷脂、蛋黄卵磷脂)的氧化指数、碘价、紫外吸收光谱及薄层层析,并用具有不同氧化指数的卵磷脂用二次乳化蒸发法制备MTX脂质体,测定它们包裹MTX的百分率。初步表明:卵磷脂对药物包裹率随其氧化指数的升高而降低,同时薄层层析的杂质点亦增多。实验结果提示,用氧化指数在0.2以下,碘价在60左右,以及薄层层析一个点的卵磷脂制备MTX脂质体可以得到较高的包裹率。 相似文献
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三磷酸腺苷脂质体的研究 总被引:5,自引:0,他引:5
本文就提高脂质体的药物包裹率,对质备方法进行了研究,提出了新的制备方法---改良乳化法(IEV),是ATP脂质体的药物包过率达到38.9%,超过文献方法,此法在国内外尚未见报道。选用草果滤技术分离未包裹的药物,用辐射灭菌法达到灭菌。这些方法对脂质体的 工业化生产有潜在的实用价值。 相似文献
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三尖杉酯碱脂质体的制剂研究 总被引:1,自引:0,他引:1
本文探讨三尖杉酯碱脂质体的较佳制备方法。表明用转相蒸发法(REV)制备时影响三尖杉酯碱脂质体包裹率的因素与大多数水溶性药物脂质体的影响因素相同。提出并经实验证实,以稠厚型脂质体贮存可减少内包三尖杉酯碱的渗漏。实验还表明脂质体100℃30分钟灭菌和10℃以下贮存五个月,制品的结构、粒度和包裹率均无明显改变,溶血试验合格。但在40℃加速实验1至3个月制品产生溶血,此溶血与卵磷脂的氧化有明显相关性。 相似文献
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靶向给药系统——青蒿酯脂质体的制备研究 总被引:3,自引:0,他引:3
采用乳化法制备了多层的青蒿酯脂质体,探讨了其制备工艺、荷电性、胆固醇含量及附加剂对青蒿酯脂质体包裹率的影响。结果表明,带正电荷的脂质体其包裹率明显高于中性或带负电荷的脂质体,而类脂中胆固醇含量及附加剂对包裹率均无明显影响,最佳处方组成的包裹率为3.63±0.09%。采用冷冻干燥技术可获得稳定性较好的脂质体冻 相似文献
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药物载体空白脂质体前体的制备及性质的研究 总被引:22,自引:0,他引:22
以蛋黄卵磷脂、胆固醇为膜材,加入适量的高分子表面活性剂,选择合适的支持剂,采用冷冻干燥法制备了空白脂质体前体,并用它作为药物载体,将药物溶液分散在载体中,制成药物脂质体.研究了空白脂质体前体的再分散性及物理稳定性.空白脂质体前体再分散性良好,平均粒径为0.75μm,粒径分布比较集中,在室温下贮存7个月、9个月后再分散其平均粒径分别为081μm、084μm,对5 Fu的包裹率也没有发生显著改变。用5 Fu,阿霉素(ADM)等为模型药物,考察了影响药物脂质体包裹率的因素,并将最优条件固定.研究结果表明:空白脂质体水相的pH值、离子强度、再分散药物溶液的浓度(即药物与磷脂的重量比)对药物包裹率有显著影响. 相似文献
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目的:脂质体前体的制备解决了脂质体分散系的物理不稳定性:如药物的渗漏、粒子的聚集以及磷脂在液态下的氧化、水解,为脂质体在临床上的应用提供了一个行之有效的方法,它使脂质体以固态形式贮存,只是在临用前加入分散介质即可再分散形成脂质体。方法:对近年来国内外脂质体前体的研究情况做文献检索,介绍了各种制备方法及影响新脂质体粒径和药物包裹率的因素。结果:通过适当的方法及选择合适的支持剂,可以制备出稳定性好、包裹率高的脂质体前体。结论:对脂质体前体的进一步研究有一定的意义 相似文献
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采用融熔法制备了氨甲喋吟(MTX)多相脂质体,并进行了抑瘤活性、小鼠急性毒性、家兔亚急性毒性和安全性实验。结果表明多相脂质体剂型显著提高了 MTX 对小鼠 EC 和 L615瘤株的抑瘤活性。急性毒性实验结果表明 MTX 多相脂质体和 MTX 水溶液的 ivLD_(50)值无显著性差异。亚急性毒性实验表明 MTX 多相脂质体大剂量给药时可出现肝细胞变性坏死。安全性实验未见异常反应。 相似文献
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The solubilization of dimyristoylphosphatidylcholine (DMPC) liposomes by the weak electrolyte drug, cefotaxime (CFX), has been studied as a function of pH, DMPC, temperature, presence of cholesterol (CHOL), and method of liposome preparation. At 7.5mMCFX the lag time for solubilization increased, the rate of solubilization decreased, and the minimum turbidity reached increased as a function of DMPC at pH 1.0 and 40C. Solubilization was most pronounced at pHs below the pKa but inhibited at least one pH unit above the pKa. The critical mole ratio of unionized CFX:DMPC, Rec, for solubilization was estimated to be 0.12. Reducing the temperature slowed the rate of solubilization as did the addition of CHOL. Encapsulation of CFX in liposomes did not significantly reduce CFX degradation, k1=0.048h-1 at 40C and a complex of DMPC and a degradation product of CFX precipitated as rectangular crystals. As a result, an increase in the turbidity of solubilized systems was observed from about 20h to 48h depending on the conditions. Liposomes in the gel state or with at least 20% CHOL did not undergo an apparent reversal of solubilization. It is concluded that the inclusion of weak electrolyte drugs existing predominantly as the unionized species in liquid crystalline state liposomes may undergo a slow solubilization process not necessarily recognized during characterization. 相似文献
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《Drug delivery》2013,20(4):257-264
AbstractMultilamellar vesicles (MLV) containing phosphatidyl choline (PC), cholestrol (CHOL), and stearylamine (SA) in the molar ratio of 7:2:0.2 were prepared by the thin film hydration method. Low-molecular-weight heparin (LMWH, MW: 3000) was conjugated with the MLV using carbodiimide (EDC). Infrared, Raman, and nuclear magnetic resonance spectra and DSC of each sample (MLV, LMWH, and MLV-LMWH) were obtained, enabling the authors to determine the chemical changes that occurred in the MLV structure at the end of the conjugation step. In addition, the changes in the chemical structures of the conjugated samples were revealed by the use of elemental analysis. Particle size analysis was used to determine the difference between the sizes of MLV and MLV-LMWH. In order to study the effect of LMWH on the behavior of MLV-LMWH in blood, osmotic fragility (in saline and plasma), hemolytic activity, and plasma recalcification time tests were carried out. These tests showed that it was possible to construct liposomes that would not induce reactions in the blood and would have potentially longer half-lives in the circulation. 相似文献
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紫杉醇是近几年来被广泛应用于临床的新型广谱抗肿瘤药物,但由于其水溶性差,传统注射剂把紫杉醇溶于聚氧乙烯蓖麻油与无水乙醇混合溶媒中增加水溶性,但聚氧乙烯蓖麻油在体内会产生毒副作用。用普通载体或修饰和改性的载体载药可以显著增强紫杉醇的药效或降低毒副作用,也可对紫杉醇进行改性和结构修饰以增加其水溶性,降低紫杉醇的毒副作用。本文对紫杉醇的应用现状、不良反应和紫杉醇新剂型进行综述。 相似文献
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丁卡因脂质体凝胶剂的研究 总被引:1,自引:0,他引:1
目的:研制丁卡因脂质体凝胶剂,为临床新制剂的开发提供参考。方法:以逆相蒸发—超声法等制备丁卡因脂质体凝胶剂;并采用改良Franz扩散池体外经皮渗透实验技术,对丁卡因脂质体凝胶剂及其普通凝胶剂的经皮渗透作用进行了比较。结果:丁卡因脂质体平均粒径为105.5 nm,平均包封率为 63.8%;体外透皮实验中,12 h累积透皮吸收百分率(Q%)为34.6%,明显高于普通凝胶制剂(17.7%);皮内药物滞留百分率(Q_滞%)分别为24.6%,明显高于普通凝胶制剂(0.65%)。结论:丁卡因脂质体凝胶剂有望成为适于临床给药的一种新剂型。 相似文献
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