贝伐单抗多囊脂质体的处方优化及体外释放特性研究

摘要

目的:制备具有缓释作用的贝伐单抗(BEV)多囊脂质体(BEV-MVLs),并对其体外释放特性进行研究.方法:采用复乳法制备BEV-MVLs,以有机相中三油酸甘油酯(TO)的浓度、1,2-二油酰基磷脂酰胆碱(DOPC)-胆固醇(CH)的比值(mol/mol)、外水相中L-赖氨酸的浓度为因素,以包封率为指标,采用Box-Behnken设计-响应面法对处方进行优化.采用倒置荧光显微镜和扫描电镜观察BEV-MVLs的形态,激光粒度仪测定其粒径,高效液相色谱法测定BEV含量并计算其包封率和体外累积释放度.结果:最优处方为有机相中TO 2.72 mmol/L、DOPC-CH比值0.67(mol/mol)、外水相中L-赖氨酸40 mmol/L.所制BEV-MVLs的包封率为(80.65±4.42)%(n=3),与预测值的相对误差为2.54%;脂质体外观呈球形,大小较均匀,为典型的非同心囊泡结构,平均粒径为16.80 μm;30 d的体外累积释放度约为92%.结论:成功制得具有缓释作用的BEV-MVLs,其包封率达到预期效果.%OBJECTIVE:To prepare Bevacizumab(BEV)multivesicular liposomes(BEV-MVLs)with sustained-effect,and to study their in vitro release characteristics. METHODS:BEV-MVLs were prepared by double emulsion method. Box-Behnken design-response surface methodology was used to optimize the prescription with the concentration of glycerol trioleate(TO)in organic phase,ratio of 1,2-dioleoyl-sn-glycero-3-phosphocholine(DOPC)-cholesterol(CH)(mol/mol),the concentration of L-lysine in external water phase as factors,using encapsulation rate as index. The morphology of BEV-MVLs was observed by inverted fluorescence microscope and SEM;particle size was determined by laser particle size analyzer;the BEV content was determined by HPLC and calculate the encapsulation rate and in vitro accumulative release rate.RESULTS:The optimized prescription was as follows as TO of 2.72 mmol/L in organic phase,DOPC-CH ratio of 0.67(mol/mol)and L-lysine of 40 mmol/L in external water phase. The encapsulation rate of BEV-MVLs was(80.65±4.42)%(n=3),and relative error of it to predicted value was 2.54%. The liposomes were spherical in appearance shape and uniform in size,and they were typical non-concentric vesicle structure with average particle size of 16.80 μm. 30 d in vitro accumulative release rate was about 92%. CONCLUSIONS:Prepared BEV-MVLs show sustained-effect,and their encapsulation rate reaches the expected effect.