重组人粒细胞集落刺激因子壳聚糖胶囊的制备和体外释药特性

Study on the preparation and the in vitro colon-specific delivery of HPMCP-coated recombinant human granulacyte colony-stimulating factor chitosan capsule

目的 :制备人重组粒细胞集落刺激因子 (rhG CSF)冻干粉剂壳聚糖胶囊 ,并对其体外释药性能进行评价。方法 :将rhG CSF冻干粉剂装入壳聚糖胶囊中 ,再以邻苯二甲酸羟丙基甲基纤维素 (HPMCP)包裹胶囊 ,用氮兰四唑蓝 (MTT)比色法测定其在人工胃液及小肠液中的体外释放性能。将荧光素钠 (FS)作为模型化合物在相同条件下进行实验 ,以激发波长 470nm、发射波长 5 13nm荧光检测FS壳聚糖胶囊在人工大肠液中的体外释放性能。用扫描电镜法评价壳聚糖胶囊在大肠内容物中的降解作用。结果 :在人工大肠液中壳聚糖具有明显降解作用。rhG CSF壳聚糖胶囊在人工胃液 (2h)和人工小肠液 (6h)内累积释药量为 (15 .5± 6 .5 ) % ,n =6。而在人工大肠液中 ,FS壳聚糖胶囊 4h释药基本完全。结论 :用HPMCP包膜的rhG CSF壳聚糖胶囊具有潜在的结肠靶向释药特性。

OBJECTIVE To prepare recombinant human granulocyte colony-stimulating factor (rhG-CSF) chitosan capsules for colon-specific delivery and to evaluate in vitro release of this dosage form. METHODS rhG-CSF lyophilized powder was filled in the chitosan capsule and the capsule then was coated with hydroxypropylmethylcellulose phthalate (HPMCP). The in vitro release of the capsule in artificial gastric juice or in man-made small intestinal juice was carried out with the MTT colorimetry to determine the contents of rhG-CSF. However, due to the difficult determination of rhG-CSF when coexisted with the artificial large intestinal liquid, fluorescein sodium (FS) was chosen as a model compound to observe the release of the capsule in this medium with fluorospectrophotometer to analyze FS. The degradation of the chitosan capsule in the rat cecum medium was evaluated by scanning electron microscope. RESULTS The accumulative release of rhG-CSF chitosan capsule was ( 15.5± 6.5)%, n=6,within 8 h in artificial medium of stomach (2 h) and small intestine (6 h), while the release reached to about 100% for FS chitosan capsule in the case of the large intestinal liquid for 4h, the significant degradation of the chitosan capsule can be observed in the rat cecum content. CONCLUSIONS HMPCP-coated rhG-CSF chitosan capsules have the potential to release the drug in the colon.