化妆品用果酸脂质体的制备研究

用反相蒸发法制得平均粒径为 164nm的果酸脂质体。研究了果酸的质量浓度对包封率的影响 ,脂质体溶液的质量浓度和温度对泄漏率的影响 ,稳定剂丙二醇的较佳质量浓度。结果表明 ,当果酸质量浓度是0 3mg/mL时可以得到 2 8%的包封率 ,丙二醇的较佳质量浓度是 5g·L-1～ 15g·L-1,温度升高使脂质体的泄漏率增加。     

乳化法制备聚乙烯醇修饰的果酸脂质体

采用乳化法制备聚乙烯醇修饰的包封果酸的脂质体,考察脂质体的微观形态,测定包封率、粒径和Zeta电位,对其稳定性进行研究,并与大豆卵磷脂脂质体的性质进行了比较。电镜照片显示两种脂质体为圆球状,实验结果表明聚乙烯醇的掺入使脂质体的包封率和粒径增加,Zeta电位的绝对值降低,这说明聚乙烯醇包覆在脂质体的表面。在酸性环境下,相比较于大豆卵磷脂脂质体,聚乙烯醇修饰的脂质体能够更加缓慢释放包封的果酸,其泄漏率随着pH的减小和储存时间的增加而增加,并且具有较好的稳定性。     

聚乙烯醇包覆的果酸脂质体的制备及性质研究

用聚乙烯醇(PVA)包覆脂质体来提高脂质体的稳定性。先用反相蒸发法制备果酸脂质体，然后将PVA溶液与果酸脂质体混合即可制得PVA包覆的脂质体。电镜照片与粒径证明PVA在脂质体外形成了一层膜。相比较于未包覆的脂质体，PVA包覆的脂质体的包封率和粒径都有所增加，泄漏率降低，其包封率随果酸质量浓度的增加而增加，泄漏率随时间和果酸／脂质体质量比的增加而增加，但低于未包覆的脂质体。通过测定粒径和泄漏率的变化说明包覆PVA的脂质体要比未包覆的稳定。     

复乳法制备聚乙烯醇修饰果酸脂质体

采用复乳法制备聚乙烯醇修饰的包封果酸的脂质体。研究了乳化温度、乳化时间、聚乙烯醇的浓度以及溶剂去除温度对脂质体包封率的影响,探讨了提高包封率的方法。实验结果表明,在25℃下,ρ(PVA)=3 g.L-1,初乳乳化7 min,复乳乳化15 min,并且溶剂在25℃下去除有利于提高脂质体的包封率,经实验条件优化后得脂质体的包封率为58.32%。     

α-硫辛酸脂质体的制备及质量评价

以大豆磷脂和胆固醇为膜材,采用薄膜-超声乳化分散法制备了α-硫辛酸脂质体。研究了配方中不同组分的比例对包封率的影响,并对脂质体的结构和形态、稳定性、表面电位、存贮条件进行了考察。结果表明,在大豆磷脂、胆固醇、α-硫辛酸的质量比为5∶1.5∶0.08时,制备的脂质体包封率为80.9%。该方法制备的α-硫辛酸脂质体为球形的单室结构,平均粒径为237 nm左右,表面电位为负,脂质体乳液的pH=6.5,适宜的贮存条件是3～5℃冰箱冷藏。     

维生素C脂质体的制备与研究

采用改进薄膜法制备维生素C脂质体，以卵磷脂：胆固醇=6：1制成空白脂质体，以空白脂质体：维生素C=9：2，超声处理3min，并经稳定化处理后得到维生素C脂质体，包封率最高可达18．09％；电子显微镜下观察结果显示产品为单室脂质体，粒径集中在20～50nm之间；低温贮存环境有利于脂质体的稳定。     

干扰素脂质体的制备及理化性质分析

目的　制备干扰素α2b脂质体 ,分析其理化性质。方法　采用旋转逆相蒸发法制备干扰素α2b脂质体 ,通过正交试验进行制备条件的优选 ,电镜观察其粒径大小 ,酶联免疫分析法测定包封率 ,并观察脂质体的稳定性。结果　干扰素α2b脂质体平均粒径为 98. 6nm ,最高包封率为 78 .2 3% ,脂质体存放于 4℃及 - 2 0℃稳定性良好。结论　本试验方法制备的脂质体包封率高 ,理化性质较稳定。     

维生素C脂质体的制备与研究

采用改进薄膜法制备维生素C脂质体,以卵磷脂:胆固醇=6:1制成空白脂质体,以空白脂质体:维生素C=9:2,超声处理3min,并经稳定化处理后得到维生素C脂质体,包封率最高可达18.09%;电子显微镜下观察结果显示产品为单室脂质体,粒径集中在20～50nm之间;低温贮存环境有利于脂质体的稳定.     

格列齐特脂质体的制备及质量评价

采用薄膜分散法制备格列齐特脂质体,以粒径和包封率为考核指标,通过单因素实验和正交实验优化制备条件,测定最优条件制备格列齐特脂质体的平均粒径和包封率。确定最优制备条件为:药脂比1∶10(g∶g)、超声时间10min、成膜温度60℃、缓冲液pH值6。所制备脂质体的平均粒径为(108.3±12.4)nm、包封率为(72.19±3.6)%、平均Zeta电位为(-40.8±2.3)mV,且在4℃下保存稳定性好。电镜照片显示,所制备脂质体圆整度好、粒径均一、无粘连。表明采用薄膜分散法制备格列齐特脂质体工艺稳定,质量可控。     

脱氧氟尿苷脂质体的制备

目的建立脱氧氟尿苷(DFUR)脂质体的制备工艺。方法采用逆向蒸发法制备DFUR脂质体,并以包封率为参考指标,进行正交试验优化该脂质体的配方。以优化的配方制备脂质体,观察其微观形态,测定粒径、包封率及稳定性,并进行体外释药实验。结果制备DFUR脂质体的最佳配方为:卵磷脂/胆固醇(摩尔比)为2∶1,有机相/水相(体积比)为5∶1,DFUR浓度为2mg/ml,磷酸盐缓冲液pH值为7.0。以此配方制备,脂质体包封率可达52.15%。3批DFUR混悬液,粒径小于220nm的粒子比率均在70%以上,显微镜下观察可见,脂质体呈球形或椭圆形,粒径范围在0.15μm～1.00μm之间。4℃保存49d,脂质体的稳定性良好。其累积释放率远低于原料药浓度。结论已建立了DFUR脂质体的制备工艺,该工艺操作简便可靠,所需设备简单,稳定性较好,可用于包埋水溶性药物。     

禽传染性支气管炎病毒脂质体核酸疫苗的制备

目的制备禽传染性支气管炎病毒脂质体核酸疫苗,并优化其制备工艺。方法采用逆向蒸发法制备禽传染性支气管炎病毒脂质体核酸疫苗,通过正交试验进行制备条件的优化,用荧光法测定脂质体的包封率。筛选制备高包封率脂质体核酸疫苗的最佳条件,测定脂质体粒径,并对疫苗免疫效果进行检测。结果制备高包封率的禽传染性支气管炎病毒脂质体核酸疫苗的工艺为:卵磷脂、胆固醇的比例为2∶1(摩尔比),转速为150r/min,温度为45℃,包封率可达80.31%。脂质体粒径平均为149nm,脂质体核酸疫苗显著提高了疫苗的免疫效果。结论按本工艺制备的禽传染性支气管炎病毒脂质体核酸疫苗包封率高,脂质体粒径均一,免疫效果良好。     

冻干茶多酚脂质体的制备及其质量

目的制备冻干茶多酚脂质体,并进行质量评价。方法采用不同种类及浓度的冻干保护剂制备冻干茶多酚脂质体,检测其包封率和有效粒径,筛选最佳冻干保护剂及其最适浓度,并对冻干茶多酚脂质体的形态、结构、粒径分布、Zeta电位和稳定性等性质进行观察。结果最佳冻干保护剂为15%(w/v)的蔗糖。所制备的冻干茶多酚脂质体再分散性良好;呈圆球形或椭球形,结构为大单室脂质体;有效粒径为(170.4±3.7)nm;Zeta电位为-60.5mV;在4℃条件下稳定性良好。结论已成功制备冻干茶多酚脂质体,其各项质量指标良好。     

人用狂犬病毒脂质体疫苗的制备及性质

目的制备人用狂犬病毒脂质体疫苗,并考察其制剂学及毒理学性质。方法以氢化大豆磷脂、胆固醇、十八胺为原料,采用反相蒸发法(REV)制备脂质体,加入纯化狂犬病毒抗原,以冻干重建法(DRV)制备狂犬病毒脂质体疫苗。在电镜下观察其形态,测定其包封率和体外释放率,用激光衍射粒度分析仪测定其粒径分布及平均粒径,并进行局部刺激性、过敏反应及异常毒性试验。结果所制备的狂犬病毒脂质体疫苗形态呈圆形或椭圆形,粒径分布均匀,平均粒径为12.25μm左右,包封率在60%以上。无刺激性,无异常毒性,过敏反应检测合格。结论所制备的狂犬病毒脂质体疫苗性质稳定,可作进一步研究。     

Liposome Microencapsulation for the Surface Modification and Improved Entrapment of Cytochrome c for Targeted Delivery

In this study, we established a procedure based on the microencapsulation vesicle (MCV) method for preparing surface‐modified liposomes, using polyethylene glycol (PEG) and a site‐directed ligand, with high entrapment efficiency of cytochrome c (Cyt c). For preparing a water‐in‐oil (W/O) emulsion, egg phosphatidylcholine and cholesterol were dissolved in organic solvents (O phase) and emulsified by sonication with aqueous solution of Cyt c (W₁). Although the dispersion stability of the W₁/O emulsion was low when n‐hexane was used to dissolve the lipids in the O phase, it was substantially improved by using mixed solvents consisting of n‐hexane and other organic solvents, such as ethanol and dichloromethane (DCM). The W₁/O emulsion was then added to another water phase (W₂) to prepare the W₁/O/W₂ emulsion. PEG‐ and/or ligand‐modified lipids were introduced into the W₂ phase as external emulsifiers not only for stabilizing the W₁/O/W₂ emulsion but also for modifying the surface of liposomes obtained later. After solvent evaporation and extrusion for downsizing the liposomes, approximately 50% of Cyt c was encapsulated in the liposomes when the mixed solvent consisting of n‐hexane and DCM at a volume ratio of 75/25 was used in the O phase. Finally, the fluorescence‐labeled liposomes, with a peptide ligand having affinity to the vasculature in adipose tissue, were prepared by the MCV method and intravenously injected into mice. Confocal microscopy showed the substantial accumulation of these liposomes in the adipose tissue vessels. Taken together, the MCV technique, along with solvent optimization, could be useful for generating surface‐modified liposomes with high drug entrapment efficiency for targeted delivery.     

Preparation of liposomes using the supercritical anti-solvent (SAS) process and comparison with a conventional method

Two methods to produce liposomes encapsulating a fluorescent marker were compared: the supercritical anti-solvent (SAS) method and a conventional one (Bangham). Liposome size and encapsulation efficiency were measured to assess the methods. Micronized lecithin produced by the SAS process was characterized in terms of particle size, morphology and residual solvent content in order to investigate the influence of experimental parameters (pressure, CO₂/solvent molar ratio and solute concentration). It appears that when the lecithin concentration increases from 15 to 25 wt.%, at 9 MPa and 308 K, larger (20-60 μm) and less aggregated lecithin particles are formed. As concerns liposomes formed from SAS processed lecithin, size distribution curves are mainly bimodal, spreading in the range of 0.1-100 μm. Liposome encapsulation efficiencies are including between 10 and 20%. As concerns the Bangham method, more dispersed liposomes were formed; encapsulation efficiencies were about 20%, and problems of reproducibility have been raised.     

花粉化妆品的应用和前景

本文论述了花粉化妆品的国内外发展现状和花粉有效成分组成 ,浅析花粉护肤美容机理 ,指出花粉化妆品新世纪的发展前景。     

黄芩苷脂质体制备及包封率测定

采用逆相蒸发法,利用卵磷脂制备黄芩苷脂质体,以紫外法测定黄芩苷浓度,透析法测定黄芩苷包封率。结果表明：卵磷脂：胆固醇（m／m）为4：1,有机相：水相为3：1,黄芩苷浓度1．5mg／mL,所制得黄芩苷脂质体粒径均匀、制备量大,包封率达40．4％。