Structural and thermal properties of spray-dried methotrexate-loaded biodegradable microparticles
Structural and thermal properties of spray-dried methotrexate-loaded biodegradable microparticles
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DOI：
10.1007/s10973-012-2580-3
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发表时间：
2013-05-01
影响因子：
4.4
通讯作者：
da Silva-Junior, Arnobio Antonio
中科院分区：
文献类型：
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作者：
de Oliveira, Alice Rodrigues;Molina, Eduardo Ferreira;da Silva-Junior, Arnobio Antonio
药物与聚合物的相互作用、可生物降解微粒的结构特性、热行为和稳定性是开发新型聚合物药物释放系统的基础。本研究采用喷雾干燥法成功制备了含甲氨蝶呤（MTX）的聚（d，l-丙交酯-共-乙交酯）（PLGA）微粒。采用扫描电子显微镜、差示扫描量热法（DSC）、热重分析（TG）、X射线衍射（XRD）和载药效率等方法，研究了载MTX PLGA喷雾干燥微球中药物与聚合物比例及其相互作用的影响。对于所使用的不同药物-聚合物比率（9、18和27%m/m），鉴定出高水平的包封效率（约90%）和普遍的球形形状。热分析（DSC和TG）和XRD表明，MTX在聚合物基体中均匀分布，以无定形状态为主，分子分散稳定。因此，使用热分析数据建立了载药PLGA微粒的药物含量和结构-热性质之间的相关性。生物可降解的微粒导致MTX的热稳定性的增加，证实喷雾干燥是用于获得载MTX的PLGA微粒的有效方法。
Drug-polymer interactions, structural properties, thermal behavior, and stability of biodegradable microparticles are fundamental aspects in the developing of new polymeric drug delivery systems. In this study, poly (d,l-lactide-co-glycolide) (PLGA) microparticles containing methotrexate (MTX) were successfully obtained by spray drying. Scanning electronic microscopy, differential scanning calorimetry (DSC), thermogravimetry (TG), X-ray diffraction (XRD), and drug-loading efficiency were used to investigate the effect of drug-polymer ratio and its interactions, in a new MTX-loaded PLGA spray-dried microparticles. High levels of encapsulation efficiency (about 90 %) and a prevalent spherical shape were identified for different drug-polymer ratios used (9, 18, and 27 % m/m). The thermal analyses (DSC and TG) and XRD indicate that MTX is homogeneously distributed in the polymeric matrix, with a prevalent amorphous state in a stable molecular dispersion. Therefore, a correlation between drug content and the structural-thermal properties of drug-loaded PLGA microparticles was established using the thermal analysis data. The biodegradable microparticle leads to an increment of thermal stability of MTX, confirming that spray drying is an efficient process for obtaining MTX-loaded PLGA microparticles.