聚乳酸聚乙醇酸微球体外突释的影响因素的研究

Study on Influence Factors for Burst Release of PLGA Microspheres in vitro

目的考察几种影响干扰素α-2b聚乳酸聚乙醇酸（PLGA）微球体外释放突释的主要因素。方法在复乳法的基础上结合海藻酸钠与钙离子螯合形成缓释凝胶的原理制备微球,研究海藻酸钠种类和浓度、PLGA黏度和浓度对微球突释的影响。结果制备的微球形态圆整,结构致密,平均粒径范围为25~55μm。微球的突释随着PLGA黏度或浓度的增高而降低,随着海藻酸钠浓度的增大而增大。结论在诸多体外释放突释影响因素中,PLGA黏度及PLGA浓度的影响最为显著。

Objective To study the main influence factors on the burst release of the interferon α-2b Poly（lactide-co-glycolide）（PLGA）microspheres in vitro.Methods Microspheres were prepared by a new method which integrated the principal that sodium alginate produces ionic interaction with calcium ion to form a kind of sustained-release gel into the normal double-emulsion method.Three factors were tested to find out how they affected the burst release of microspheres.The factors included the viscosity,concentration of PLGA and the type and concentration of sodium alginate（Sa）.Results Microspheres were spherical with compact structure in their morphology and their average size ranged from 25~55 μm.The burst release of microspheres decreased with the increase of either viscosity or concentration of PLGA,and increased with the concentration increase of Sa.Conclusion The viscosity and concentration of PLGA among the influence factors of burst release played the most significant roles.