siRNA的PEG化脂质体的制备及处方的筛选  

Preparation of PEGylated cationic liposome for siRNA delivery and formulation optimization

作　　者：张梦甜 韩剑锋[1] 吴称玉 孙逊[1] 

机构地区：[1]四川大学华西药学院 靶向药物与释药系统教育部重点实验室,四川成都610041

出　　处：《华西药学杂志》2014年第4期364-367,共4页West China Journal of Pharmaceutical Sciences

摘　　要：目的制备一种递送siRNA的PEG化脂质体,通过改变处方中PEG的比例来优化处方。方法采用前体脂质体的方法制备不同PEG含量的阳离子脂质体;用超速离心法分离脂质体siRNA复合物和游离siRNA;用荧光标记法检测siRNA,求得各处方脂质体对SiRNA的包封率;考察不同处方脂质体在血清中的稳定性;测定不同处方脂质体在A549细胞上的毒性和摄取效率;筛选最终脂质体处方并测定其粒径、电位,观察形状。结果选定5%PEG含量的脂质体为最终的处方,其在50%血清中的稳定性良好,在A549细胞上的摄取效率较高且无细胞毒性,siRNA与其的包封率为72.43%,siRNA形成复合物后的形态电镜结果显示良好。结论选定和制备了具有良好体外理化性质的PEG化脂质体递送siRNA。OBJECTIVE To prepare a PEGylated liposome for siRNA delivery by particulate - based method, and optimize the PEG ratio in cationic liposomes according to their physieochemical proporties. METHODS The PEGylated cationic liposomes were prepared with particulate - based method, and free siRNA and liposome/siRNA complexes were separated by uhracentrifugation ; encapsulation efficiency of the complexes was determined by measuring free FAM - siRNA through fluorospectrophotometer, the serum stability of cationic liposomes with different PEG ratios was also investigated. The cytotoxicity and cellular uptake efficacy of the complexes were detected on A549 cells. The average diameter, Zeta potential and morphology of PEGylated liposomes were observed. RESULTS 5% PEGylated cationic liposome was selected as the optimal formulation ,whose encapsulation efficiency of 5% PEGylated liposome/ siRNA complexes was above 70%, and both the cellular uptake and the serum stability results revealed that the 5% PEGylated cationic liposomes was better than the others in this study. Meanwhile,it showed low toxicity in A549 cells. CONCLUSION The selected 5% PEGylated cationic liposomes might be a potential vehicle for the delivery of siRNA.

关 键 词：前体脂质体 PEG化阳离子脂质体 SIRNA 处方筛选 

分 类 号：R94[医药卫生—药剂学]