聚乳酸载药微球的制备研究

Preparation of drug loaded poly(lactic acid)(PLA) microspheres

聚合物微球的粒径较小,可以很好地越过阻碍物到达患病部位;并且通过控制药物的释放速率,能够实现准确给药,提高药物的利用率。聚乳酸具有良好的生物可降解性,在药物载体领域得到了广泛的应用。通过实验研究影响药物载体性能的各项因素,以硝苯地平为模型药物,采用乳化蒸发法制备载药微球,研究范德华力、药物的形态对微球和药物相容性的影响。结果表明,随着聚乳酸用量的不断加大,微球粒径逐渐增大;药物含量减少时,微球的表面光滑,且分散性较好;基于相容性规则可用于选择和设计适宜的药物载体的聚合物材料。

Polymeric microspheres have smaller diameter,and they could reach the ill site by overcoming the barriers and control the drug release rate to improve the drug bioavailability.Polylactic acid has good biodegradability and it has been widely used as drug carriers.The research work was to study the factors to affect the drug carriers＇ properties,a series of research work was carried out as follows：Nifedipine was used as a model drug,and the drug loaded microspheres were fabricated using O/W emulsion solvent evaporation method.The effects of polymer type,concentration and the initial content of the drug on the microspheres particle size distribution,structure form and the entrapment efficiency were evaluated.Moreover,the influence of different structure release properties of the microspheres was evaluated.Also,the effect of Van der Waals＇ force and the drug state on the biocompatibility was studied.Results showed that with the continuous increase of polylactic acid dosage,microspheres particle size increases gradually.The drug content reduces,the ball surface is smooth,and has good dispersion.Based on compatibility rules can be used to select and design the suitable drug carrier polymer materials.