层层自组装法制备脂质体为模板的积雪草苷镶囊

Preparation of asiaticoside capsosomes using liposome as template by layer-by-layer self-assembly method

【目的】以天然聚电解质为囊材,以积雪草苷为模型药物,制备以阳离子脂质体为模板的新型脂质体镶囊,探讨处方工艺对新型脂质体镶囊包封率的影响,优化处方工艺。【方法】利用薄膜分散法制备模板脂质体和吸附脂质体,采用层层自组装法(layer-by-layer self-assembly,LbL)制备积雪草苷镶囊。以包封率为指标,对脂质体镶囊的制备工艺进行单因素考察,应用星点设计-效应面法优化处方工艺,考察海藻酸钠和壳聚糖溶液的pH(X_1),反应转速(X_2,kr/min),反应时间(X_3,h)对包封率的影响。多元非线性模型拟合预测最优处方的包封率。【结果】经多元非线性模型拟合得到最优处方为:X_1=7.50、X_2=0.65 kr/min、X_3=0.30 h,拟合方程计算得到的最优处方的包封率为89.47%。验证实验所得积雪草苷脂质体镶囊的包封率为(88.70±0.25)%(n=3),与预测值的偏差为-0.77%。【结论】所得镶囊的包封率较高,重现性良好。

【Objective】To fabricate a novel asiaticoside-loaded capsosomes with a liposomal core, explore the effect of different factors on the encapsulation efficiency of capsosomes and optimize the preparation process.【Methods】The liposomes were prepared by the thin film dispersion method. The asiaticoside-loaded capsosomes were prepared by co-precipitation method and layer-by-layer assembly technique. The central composite design-response surface method was used to optimize the formulary of the asiaticosideloaded liposomes based on the single-factor experiments, and the p H of natural polyelectrolytes（X1）, rotating speed（X2, kr/min） and the reaction time（X3, h） were selected as independent variables. The result was fitted with multivariate nonlinear equation to predict the encapsulation efficiency of optimal formulation.【Results】The optimal prescription obtained by fitting the multivariate nonlinear model was as follows： X1=7.50, X2=0.65 kr/min and X3=0.30 h. The encapsulation efficiency of the optimal prescription fitting equation calculation was 89.47%. The encapsulation efficiency of asiaticoside-loaded capsosomes in the confirmatory experiment was（88.70±0.25） %（n=3） and the deviation from the predicted values was-0.77%.【Conclusion】The encapsulation efficiency of asiaticosideloaded capsosomes is high and the reproducibility is good.