尼莫地平前体脂质体的制备及其质量评价

目的制备尼莫地平前体脂质体,并进行质量评价,以期得到高效、低毒和稳定的尼莫地平新剂型。方法采用叔丁醇-水共溶剂冻干法制备尼莫地平前体脂质体,考察了影响药物包封率的因素,并对重建脂质体的药物含量、包封率、粒径、Zeta电位、溶血性及稳定性进行考察。结果磷脂浓度、表面电荷是影响尼莫地平脂质体包封率的主要因素。尼莫地平脂质体包封率大于98%,平均粒径为57 nm,Zeta电位小于-20 mV,无溶血性,稳定性好。结论采用叔丁醇水共溶剂冻干法获得了高包封率、粒径均一、无溶血性、稳定的尼莫地平前体脂质体制剂,可用于静脉注射给药。     

齐墩果酸新型前体脂质体大鼠小肠吸收实验研究

目的：考察齐墩果酸新型前体脂质体大鼠小肠吸收情况,探讨制备齐墩果酸新型前体脂质体的可行性。方法：采用新型前体脂质体制备方法制备齐墩果酸前体脂质体,采用大鼠离体外翻肠囊法、高效液相色谱法测定齐墩果酸前体脂质体的大鼠小肠吸收,以齐墩果酸溶液同法考察吸收情况作为对照。结果：齐墩果酸前体脂质体给药后大鼠浆膜侧药物浓度-时间曲线下面积显著大于对照组（P〈0.01）。结论：齐墩果酸前体脂质体可增加齐墩果酸的大鼠小肠吸收,初步表明齐墩果酸前体脂质体这一剂型的可行性。     

喷雾干燥法制备阿霉素前体脂质体的研究

 本文采用喷雾干燥法制备了阿霉素前体脂质体，并对其质量进行了评定。结果表明，这种前体脂质体是由表面附着薄膜的微球组成的具有流动性的粉体，与含阿霉素的水相混合后卯形成类似椭圆状的单室脂质体（阿霉素含量：1mg／ml），算术平均粒径为1．3μm，包封率可达39．9％±4．5％。     

光敏性双亲共聚物在水溶液中的胶束化行为

通过ε-己内酯改性丙烯酸酯(FAa，n=1～4)与肉桂酰氯间的酰化反应合成了一系列光敏性大单体(FAaC)，与甲基丙烯酸(MAA)在溶液中进行自由基聚合，制备了具有光敏性的双素无规共聚物(PMFAaC)。将PMFAaC在选择性溶剂中进行自组装，可以形成纳米结构的聚合物。用动态激光光散射(DLS)研究了聚合物胶束的溶液行为，同时考察了单体含量、聚合物终浓度、聚合物侧链长、pH值、离子强度及温度等因素对胶束粒径的影响。实验结果表明，PMFAaC在选择性溶剂中可自组装成胶束，其粒径及其分布对单体含量、聚合物终浓度、聚合物侧链长、pH值、离子强度等有一定的依赖性，而对温度无依赖性。进一步用紫外光使肉桂酰基发生交联反应。从而制备得到核交联且稳定的纳米胶束。用DIS表征发现交联后的胶束粒径较交联前的小。     

四种前体脂质体制剂的包封率比较及小肠吸收研究

目的:采用一种新型前体脂质体制备方法将4种不同极性的药物分别制成前体脂质体,考察此种制备方法对不同药物的适用性。方法:比较齐墩果酸、水飞蓟素、替加氟、肉苁蓉总苷4种前体脂质体制剂水合后所形成脂质体的包封率,选用齐墩果酸前体脂质体、水飞蓟素前体脂质体水合后进行离体小肠吸收实验,以考察所形成脂质体的吸收情况,从而对体内吸收情况进行预测。结果:4种前体脂质体制剂中,包封率为齐墩果酸>水飞蓟素>替加氟>肉苁蓉总苷;离体小肠吸收实验结果显示:齐墩果酸脂质体、水飞蓟素脂质体与其对照溶液相比,药时曲线下面积增大。结论:前体脂质体制备方法尤其适用于弱极性药物如齐墩果酸,制成的脂质体制剂与对照相比,明显促进了药物的吸收。     

L—门冬酰胺酶前体脂质体对小鼠毒性及对实验性肿瘤作用

目的：研究L－门冬酰胺酶（L－Asparaginase,L-A)前体脂质体（Proliposome,PL)[L-APL]iv对小鼠的毒性及对荷瘤小鼠的抗肿瘤活性。方法：以小鼠的急性毒性和外周血中白细胞数及血小板数为指标观察药物对小鼠的毒性及以荷瘤小鼠的瘤重和生命延和工率观察药物的抗肿瘤活性;结果：L－APL iV对小鼠的急性毒性与L－A相比明显降低,L－APL对正常小鼠外周血中白细胞数,血小板数无明显影响,而相同剂量L－A对小鼠外周血中白细胞数,血小板数明显降低。与对照组相比,L－APL和L－Aip可明显延长腹水型小鼠移瘤L1210,P388的存活天数,与同剂量L－A相比,L－APL高剂量有明显延长腹水型小鼠移植瘤的存活天数作用。L－APL及L－A ip对小鼠移植瘤Heps,EC实体型的肿瘤生长具有明显的抑制作用,两者抑瘤作用相近。结论：L－APL对小鼠的毒性明显小于相同剂量的L－A,L－APL不仅保持了L－A的抗肿瘤活性,而且有明显的增效作用。     

控制多种细胞在同一表面有序黏附的研究进展

体外进行多种细胞共培养体系的建立,为不同种类细胞间相互作用的研究提供了有效的途径.在细胞培养的基底表面运用化学修饰,改变其对蛋白质和细胞的吸附特性,可以良好地控制不同细胞的共培养.结合微流控技术,在同一基底上也可以达到多种细胞的共培养.本文综述这一领域近期的研究进展.     

Chitosan‐coated antifungal formulations for nebulisation

Objectives The aim of this study was to produce and characterise amphotericin B (AmB) containing chitosan‐coated liposomes, and to determine their delivery from an air‐jet nebuliser. Methods Soya phosphatidylcholine : AmB (100 : 1) multilamellar vesicles were generated by dispersing ethanol‐based proliposomes with 0.9% sodium chloride or different concentrations of chitosan chloride. These liposomes were compared with vesicles produced by the film hydration method and micelles. AmB loading, particle size, zeta potential and antifungal activity were determined for formulations, which were delivered into a two‐stage impinger using a jet nebuliser. Key findings AmB incorporation was highest for liposomes produced from proliposomes and was greatest (approximately 80% loading) in chitosan‐coated formulations. Following nebulisation, approximately 60% of the AmB was deposited in the lower stage of the two‐stage impinger for liposomal formulations, for which the mean liposome size was reduced. Although AmB loading in deoxycholate micellar formulations was high (99%), a smaller dose of AmB was delivered to the lower stage of the two‐stage impinger compared to chitosan‐coated liposomes generated from proliposomes. Chitosan‐coated and uncoated liposomes loaded with AmB had antifungal activities against Candida albicans and C. tropicalis similar to AmB deoxycholate micelles, with a minimum inhibitory concentration of 0.5 µg/ml. Conclusions This study has demonstrated that chitosan‐coated liposomes, prepared by an ethanol‐based proliposome method, are a promising carrier system for the delivery of AmB using an air‐jet nebuliser, having a high drug‐loading that is likely to be effectively delivered to the peripheral airways for the treatment of pulmonary fungal infections.     

Functional oligopeptide as a novel strategy for drug delivery

Oligopeptides, a type of short peptide, which consist of 2–20 amino acids, exhibit a variety of biological functions in drug delivery systems, such as specific targeting, cell penetration, self-assembled capacity and responsiveness to the environment. In this review, we aim to highlight the importance of functional oligopeptides for nanomedical applications and put forward the views on the future development direction of oligopeptide medicines. Oligopeptides have gained wide attentions due to their inherent properties, but the lack of understanding the mechanisms of in vivo transport behavior is the biggest problem and challenge at the present stage. Therefore, it is an important direction for the future clinical research to systematically evaluate its metabolic behavior and safety in vivo.     

喷雾干燥法制备丹参酮前体脂质体的研究

目的 提高丹参酮（tanshinone)的生物利用度及其脂质体的稳定性。方法 先采用薄膜法将丹参酮制备成脂质体混悬液，然后采用喷雾干燥法将其制备成前体脂质体。结果 丹参酮前体脂质体为干燥的球形粒子，粒度约5μm；前体脂质体水合而重建的脂质体的粒度分布与喷雾干燥前的脂质体无明显差别，脂质体呈球形或椭球形，无明显团聚现象；脂质体中的丹参酮和大豆磷脂在喷雾干燥过程中均较稳定。结论 喷雾干燥法制备丹参酮前体脂质体是可行的。