重组人粒细胞集落刺激因子缓释微球的研究

目的：研究固体／油／水法制备重组人粒细胞集落刺激因子缓释微球，为开发其缓释剂型进行初步研究。方法：以聚乳酸．聚羟乙酸共聚物（PLGA）为载体材料：用固体／油／水法和水／油／水法制备载rhG-CSF缓释微球；考察粒径大小、外观、包封率等理化性质；用MieroBCA法考察微球的体外释药特性及影响因素；用SEC-HPLC和MTT比色法初步评价了微球制备工艺过程对rhG-CSF稳定性的影响。结果：两种方法制得的微球形态圆整、分散性良好，包封率均超过80％。固／油／水法制得的微球体外释放在2周内可超过90％，而水／油／水法制得的微球在相同的时间内仅释放30％。对于固／油／水法制备过程，SEC-HPLC法测定蛋白无明显聚集体出现，MTT法测定蛋白活性无明显损失。结论：实验证明了固／油／水法制备的PLGA微球可以实现2周以上的体外缓释。

Study on PLAG Microspheres for Sustained Release of Recombinant Human Granulocyte Colony-stimulating Factor

Objective:To prepare sustained released rhG-CSF loaded microspheres by S/O/W method,and to make pre- liminary research on developing a new strategy for delivering rhG-GSF in a sustained manner.Methods:rhG-GSF loaded mi- crospheres were prepared with poly lactic-co-glycolic acid(PLGA)as carrier material by S/O/W and W/O/W methods separately. Physical and chemical characteristics of microspheres(mean diameter,morphology and drug enveloped rate)were evaluated;the release profiles of rhG-GSF from PLGA microspheres made by S/O/W and W/O/W methods were compared,the in vitro release behavior and influencing factors of the microspheres were determined by MicroBGA method;and rhG-GSF stability during en- capsulation was evaluated by SEG-HPLG;the bioactivities of rhG-GSF during the encapsulation process were determined by MTT method.Results:The 2 types of microspheres produced had similar good shape and dispersive quality as wall as a drug en- trapment efficiency of more than 80%.About 90% of encapsulated rhG-GSF prepared by S/O/W method was released out in a sustained manner from PLGA microspheres within 2 weeks,but for rhG-GSF microspheres prepared by W/O/W method,only about 30% of rhG-GSF could be released out during the same period.Size exclusion chromatograms revealed that the structural in- tegrity of released rhG-GSF from microspheres prepared by S/O/W method was nearly intact,compared to that of native rhG- CSF;MTT result revealed that S/O/W method showed good protection to rhG-CSF during producing process.Conclusions:The research investigated a PLGA polymeric microparticulate formulation of rhG-CSF,and exhibited a sustained release profile over an extended period,without showing any significant alterations in structure.Protein encapsulated PLGA microspheres by S/O/W method will be a new promising strategy for delivering therapeutic protein drugs in a sustained manner.