蔗糖八硫酸酯三乙胺梯度法制备重酒石酸长春瑞滨脂质体

 目的：制备重酒石酸长春瑞滨脂质体,并对制备工艺进行考察。方法：以蔗糖八硫酸酯三乙胺（triethylammonium sucrose octasulfate,TEA8SOS）梯度法制备重酒石酸长春瑞滨脂质体,以阳离子交换树脂分离脂质体与游离药物;并以紫外分光光度法和激光粒度仪分别测定重酒石酸长春瑞滨脂质体的包封率和粒径。结果：重酒石酸长春瑞滨脂质体包封率约为95%,粒径为129.5 nm。结论：以蔗糖八硫酸酯三乙胺梯度法制备的重酒石酸长春瑞滨脂质体包封率较高,方法可行。     

盐酸伊立替康脂质体的制备及体外释药特性研究

目的:制备盐酸伊立替康脂质体并考察其体外释药特性。方法:采用硫酸铵梯度法,通过正交试验进行盐酸伊立替康脂质体处方筛选和制备工艺研究;采用透析法考察体外释放度。结果:制备的盐酸伊立替康脂质体包封率较高,达到75·4%;通过正交设计确定最佳处方为磷脂与胆固醇质量比为2:1,硫酸铵溶液浓度为0·20mol·mL-1,孵育温度为50℃,药脂比为1:10;脂质体中药物1h释放8·09%,9h释放64·2%。结论:制备的盐酸伊立替康脂质体具有较高包封率和缓释特性。     

盐酸伊立替康脂质体的制备

目的结合脂质体这种新型给药载体的特征将盐酸伊利替康(Irinotecan,OPT-11)制备成脂质体以解决喜树碱类药物在生理条件下其结果中的内酯环易发生水解反应转变为羟酸盐形式,从而失去活性这个难问题.方法以包封率为主要评价指标,比较了传统的脂质体制备方法(薄膜分散法、乙醇注入法、反向蒸发法等)与主动载药方法-硫酸铵梯度法对伊立替康脂质体制备的影响.结果采用硫酸铵梯度法制备伊立替康脂质体可以获得较高的包封率、较大的药酯比.结论硫酸铵溶液的浓度、孵育时间和温度空白脂质体的粒径大小等是影响伊立替康脂质体包封率的主要因素.     

主动载药法制备硫酸卷曲霉素脂质体及其质量评价

目的制备硫酸卷曲霉素脂质体,建立含量和包封率的测定方法,初步考察其体外释放规律。方法采用pH梯度法制备硫酸卷曲霉素脂质体,超滤法分离脂质体与游离药物,RP-HPLC测定脂质体的含量和包封率,透析法考察脂质体的体外释放行为。结果超滤法能很好地将脂质体与游离药物分离,测定硫酸卷曲霉素脂质体的含量为10.27mg/ml,包封率为47.8%,脂质体的体外释放规律符合一级动力学过程。结论pH梯度法适于制备硫酸卷曲霉素脂质体,超滤法可用于硫酸卷曲霉素脂质体包封率的测定,制备的脂质体具有一定的缓释效果。     

盐酸伊立替康脂质体制备的影响因素考察

目的:对盐酸伊立替康的脂质体制备方法进行考察。方法:在预实验的基础上初步确定盐酸伊立替康脂质体的制备方法和处方,然后通过单因素考察初步确定影响脂质体制备的因素。结果:硫酸铵梯度法制备的盐酸伊立替康脂质体包封率较高(75.40%),且能保持药物活性。结论:采用硫酸铵梯度法制备脂质体给药系统,制备工艺简单,重现性好,质量稳定,是一种很有前途的靶向给药系统。     

硫酸铵梯度法制备伊立替康脂质体及稳定性研究

目的：制备盐酸伊立替康脂质体并考察提高脂质体稳定性的方法。方法：采用硫酸铵梯度法制备盐酸伊立替康脂质体。以粒径、外观、颜色、渗漏率作为指标，考察盐酸伊立替康脂质体的物理和化学稳定性。结果：硫酸铵梯度法制备的盐酸伊立替康脂质体呈圆球形，平均粒径为600nm，稳定性较好。结论：盐酸伊立替康脂质体不耐高温，将其制成冻干粉剂可显著提高药物稳定性。     

奥沙利铂脂质体的制备及体外释药研究

目的：制备一种包封率较高的奥沙利铂脂质体,并考察该脂质体的体外性质。方法采用多种方法制备奥沙利铂脂质体,通过单因素试验和正交试验最终确定脂质体处方。采用高效液相色谱法检测脂质体包封率, ZetaPlus 激光粒度分析仪测定脂质体粒径。同时,采用高效液相色谱法、原子吸收光谱法两种方法考察了该脂质体的体外释放情况。结果与薄膜分散法和 pH 梯度法相比,通过逆相蒸发法制备得到的了奥沙利铂脂质体包封率更高;在此基础上进行的处方筛选试验确定了最优处方工艺为药脂比1∶7.5,胆磷比1∶2,超声功率195 W,超声时间3 min;体外释放试验结果表明,通过高效液相色谱法和原子吸收光谱法测定的奥沙利铂脂质体24 h 的累计释放率分别为25.0%和33.6%。结论通过逆相蒸发法制备得到的奥沙利铂脂质体包封率高,且具有较高的稳定性和一定的缓释作用。     

乙二胺四乙酸铵梯度法制备盐酸伊立替康脂质体

目的制备盐酸伊立替康脂质体,考察包封率及粒径的影响因素。方法采用乙二胺四乙酸铵梯度法制备盐酸伊立替康脂质体,以阳离子交换树脂分离脂质体和游离药物,并以紫外分光光度法和激光粒度仪分别测定盐酸伊立替康脂质体的包封率和粒径;考察不同处方和制备工艺对脂质体包封率及粒径的影响。结果通过处方工艺优化,盐酸伊立替康脂质体包封率达到95.73%,粒径为112.8 nm。结论以乙二胺四乙酸铵梯度法制备的盐酸伊立替康脂质体包封率较高,方法可行。     

盐酸伊立替康脂质体的制备及包封率的测定

目的制备盐酸伊立替康脂质体,建立包封率测定方法。方法采用乙二胺四乙酸铵梯度法制备盐酸伊立替康脂质体;以阳离子交换树脂离心法分离脂质体和游离药物;采用紫外可见分光光度法测定脂质体包封率。结果阳离子交换树脂柱对质量浓度为1.0~2.4 g.L-1伊立替康能够完全吸附,且对空白脂质体无吸附,空白脂质体回收率达99.73%;采用紫外可见分光光度法测定盐酸伊立替康含量,在372 nm波长下,空白辅料对药物测定无干扰,盐酸伊立替康质量浓度在2.5~45.0 mg.L-1内线性关系良好(r=0.999 9),精密度和回收率均符合要求;盐酸伊立替康脂质体包封率为95.4%。结论乙二胺四乙酸铵梯度法适用于制备盐酸伊立替康脂质体,所建立的分析方法简单快速,准确可靠,可用于盐酸伊立替康脂质体包封率的测定。     

聚乙二醇对盐酸伊立替康脂质体体外释放及在不同稀释介质中稳定性的影响

目的:考察不同聚乙二醇含量对盐酸伊立替康脂质体体外释放特性及在不同稀释介质中稳定性的影响。方法:采用乙二胺四乙酸铵梯度法,以聚乙二醇2000含量分别为0、8、14、20、26 mg/ml的聚乙二醇2000-二硬脂酰磷脂酰乙醇胺(m PEG2000-DSPE)制备盐酸伊立替康脂质体,测定其包封率和粒径,评价其体外24 h内的累积释放度和在生理氯化钠溶液与5%葡萄糖注射液中的稳定性。结果:随着m PEG2000-DSPE含量的增加,盐酸伊立替康脂质体体外24 h累积释放度逐渐减小;以生理氯化钠溶液及5%葡萄糖注射液稀释后,随着m PEG2000-DSPE含量的增加,盐酸伊立替康脂质体的包封率和粒径变化均减小;当聚乙二醇2000质量浓度增加至20、26 mg/ml时,脂质体包封率和粒径基本不再变化。结论:m PEG2000-DSPE的加入可减慢盐酸伊立替康脂质体的体外释放,提高其在不同稀释介质中的稳定性。     

Novel sulfobutyl ether cyclodextrin gradient leads to highly active liposomal irinotecan formulation

Objectives Liposomal delivery of irinotecan could provide protection against drug hydrolysis, deliver more active lactone form to tumours and prolong irinotecan exposure time. Nevertheless, conventional drug‐loading technologies have typically resulted in undesired drug retention properties. To resolve the problem, a modified gradient loading method was developed and the resulting formulations were evaluated in a systemic manner. Methods Irinotecan was loaded into liposomes using a novel sulfobutyl ether beta‐cyclodextrin (sbe‐CD) gradient. The effect of drug‐to‐lipid ratio (D/L) and polyethylene glycol (PEG) grafting density were investigated. Drug release experiments were performed in ammonium‐containing medium based on the fluorescence dequenching phenomenon of irinotecan. Pharmacokinetic studies were performed in normal balb/c mice treated with different formulations. To compare the anti‐tumour effect of different formulations, an RM‐1 prostate cancer model was used. Acute toxicity studies were performed in healthy female c57 mice. Key findings Irinotecan could be encapsulated into liposomes with > 90% loading efficiency at a high drug‐to‐lipid mass ratio (> 0.5). In‐vitro release experiments revealed that sbe‐CD anion was more able to retain irinotecan than sulfate. Moreover, the elevated D/L ratio elicited decreased drug release kinetics. Both trends had also been observed when the effects of anions and D/L ratio on half‐life of irinotecan were assessed. Pegylated liposomal irinotecan loaded with sbe‐CD/triethylammonium gradient had irinotecan half‐life values ranging from 9.4 to 13.1 h, surpassing vesicles prepared by the triethylammonium sulfate method (～4.5 h). In the RM‐1 tumour model, all the liposomal irinotecan formulations were more therapeutically active than free irinotecan and the formulation with a high D/L ratio was the most efficacious. Moreover, the high D/L formulation might be less toxic than free irinotecan based on acute toxicity studies. Conclusions The novel sbe‐CD gradient could mediate effective irinotecan loading and improve irinotecan retention, thus resulting in highly active liposomal irinotecan formulations. The improvement in drug retention might be associated with the formation of complicated aggregates inside vesicles.     

石杉碱甲脂质体制备及包封率的影响因素

目的建立石杉碱甲脂质体(huperzine A liposome,HUPA-L)的制备方法。方法采用pH梯度、硫酸铵[(NH4)2SO4]梯度、乙二胺四乙酸铵(NH4EDTA)梯度方法制备HUPA-L,以阳离子交换树脂分离脂质体和游离药物,HPLC法测定HUPA-L的包封率,并考察温度、孵化时间及药脂比对HUPA-L包封率的影响。体外释放实验研究HUPA-L的释放行为。结果硫酸铵梯度法制备的HU-PA-L包封率最高,包封率随着硫酸铵浓度和温度的升高而增加,随着药脂比的降低而增大,当药物与磷脂质量比小于1∶100时,HUPA-L包封率可达100.0%;HUPA-L体外释放呈现明显的缓释效果。结论硫酸铵梯度法是制备HUPA-L优选方法,硫酸铵的浓度、温度和药脂比是影响包封率的重要因素。     

粉防己碱脂质体的制备及其稳定性研究

目的:比较粉防己碱脂质体2种制备方法。方法:采用硫酸铵梯度法和薄膜分散法制备粉防己碱脂质体,从渗漏率、粒径大小、磷脂含量3个方面进行稳定性比较,从包封率方面进行质量比较。结果:硫酸铵梯度法制备的粉防己碱脂质体包封率高达81.1%,且稳定性好;薄膜分散法包封率仅为32.9%,且稳定性欠佳。结论:硫酸铵梯度法较薄膜分散法制备粉防己碱脂质体更优。     

In vitro and in vivo evaluation of sanguinarine liposomes prepared by a remote loading method with three different ammonium salts

Sanguinarine liposomes were prepared by a remote loading method using three different ammonium salts. A series of studies, including in vitro release, in vitro and in vivo anti-tumor effects and pharmacokinetics in rats, were conducted. The three liposomes showed pH-sensitive release characteristics in vitro, but there were obvious variations in their release profiles. Among the three liposomes, the liposomes made using ammonium citrate and phosphate possessed better anti-tumor activity in vitro and in vivo, compared with the liposome using ammonium sulfate. Pharmacokinetics test results in rats indicated that sanguinarine liposomes have notably elevated AUC (P<0.05) and markedly lower CL (P<0.05) compared with the solution, but there were no obvious differences between the three liposomes. The present study may be useful for better understanding and better choice of a suitable ammonium salt for the remote loading method.     

苦参碱隐形脂质体的包封率测定和体外释放度研究

目的:研究苦参碱隐形脂质体的包封率测定方法,考察其体外释放度。方法:采用硫酸铵梯度法制备苦参碱隐形脂质体;用葡聚糖凝胶G-100柱分离脂质体和游离药物,并用反相高效液相色谱法测定脂质体的包封率;用《中国药典》中溶出度第二法测定其体外释放度。结果:制得脂质体的包封率为52.40%;苦参碱检测浓度的线性范围为0.005～0.200mg·mL-1(r=0.999 9);平均回收率为98.36%(RSD=0.95%);脂质体的体外释放规律符合Higuchi方程。结论:本方法简单、快速、准确、重现性好,可用于该脂质体的包封率和体外释放度的测定。