PEG6000修饰的流感疫苗脂质体的制备和稳定性

Preparation and Stability of Influenza Vaccine Liposomes Modified by PEG6000

目的筛选出PEG6000流感疫苗脂质体的最佳制备工艺并且评价其稳定性。方法将小鼠免疫7 d,通过MTT法确定加入PEG6000的最佳摩尔百分比和最佳制备工艺。采用冻融冻干法制备PEG修饰的流感疫苗脂质体,将样品分别储存于不同温度[4℃、(25±2)℃、(37±2)℃]下,在设定时间取样测定包封率、胸腺指数和抗体滴度,考察其物理和生物稳定性。结果MTT实验结果表明,PEG6000占磷脂摩尔百分比为4%时为最佳用量(P<0.01),最佳工艺为后修饰法。PEG6000修饰的流感疫苗脂质体冻干粉在(37±2)℃条件下放置6个月后,包封率仍在80%以上;在(25±2)℃放置3个月后抗体滴度比>4,表明仍具有较好的免疫效应。结论PEG6000占磷脂摩尔百分比为4%时为最佳用量,采用后修饰法制备为最佳工艺;PEG6000脂质体具有良好的物理稳定性及生物稳定性。

Objective To screen out the best method of PEG6000 modified liposomes for influenza vaccine and evaluate its stability.Methods After 7 d of immunization,the optimal molar percentage of PEG6000 and the optimal preparation method were assumed by MTT method.The PEG-modified influenza vaccine liposomes were prepared by freeze-thaw freeze-drying method.The samples were stored at different temperatures(4℃,25±2℃,37±2℃),and the encapsulation rate and thymus index and antibody titer were measured at a fixed time.So the physical and biological stability of the samples were investigated.Results The MTT experiment showed that PEG6000 was the best dosage when the molar percentage of phospholipid was 4%(P<0.01),and the best process was post-modification method.The entrapment rate of PEG6000 modified liposome for influenza vaccine was still higher than 80%when stocked at 37±2℃for 6 months.At 25±2℃for 3 months,the antibody titer was more than4,indicating that the antibody still had nice immune effection.Conclusions PEG6000 best dosage of phospholipid when the molar percentage of PEG6000 is 4%,and post-modification method is the best preparation process.PEG6000 liposome has nice physical stability and biological stability.