Zaghloul A A
Department of Pharmaceutics, Faculty of Pharmacy, Kuwait University, Safat.
Pharmazie. 2006 Sep;61(9):775-9.
The purpose of this work was to study the effect of organic solvent and surfactant type on the in vitro release behavior in general and on the burst release in particular of beta-estradiol from PLA/PLGA microspheres. Also the effect of these variables on the encapsulation efficiency was investigated. The microspheres were prepared by solvent evaporation technique using dichloromethane (DCM), ethyl acetate (EtAc), tetrahydrofuran (THF), chloroform (CHCl3) or acetone (AC) as organic solvent and polyvinyl alcohol (PVA), Tween 80, sodium lauryl sulfate (SLS) or benzalkonium chloride (BKCI) as surfactant. The obtained microspheres were tested for encapsulation efficiency and in vitro drug release using 50% methanol/buffer pH 7.4 as dissolution medium. EtAC and PVA formulations showed the highest encapsulation efficiency and the lowest burst release. These microspheres were further characterized for particle size distribution, SEM and zeta potential. The results suggested that these materials could be starting materials to prepare a beta-estradiol biodegradable controlled delivery system.
本研究旨在探讨有机溶剂和表面活性剂类型对聚乳酸/聚乳酸-羟基乙酸共聚物（PLA/PLGA）微球中β-雌二醇体外释放行为的总体影响，特别是对突释的影响。同时还研究了这些变量对包封率的影响。采用溶剂挥发法，以二氯甲烷（DCM）、乙酸乙酯（EtAc）、四氢呋喃（THF）、氯仿（CHCl3）或丙酮（AC）为有机溶剂，聚乙烯醇（PVA）、吐温80、十二烷基硫酸钠（SLS）或苯扎氯铵（BKCI）为表面活性剂，制备了微球。以50%甲醇/ pH 7.4缓冲液为溶出介质，对所得微球进行包封率和体外药物释放测试。EtAC和PVA配方显示出最高的包封率和最低的突释。对这些微球的粒径分布、扫描电子显微镜（SEM）和zeta电位进行了进一步表征。结果表明，这些材料可作为制备β-雌二醇可生物降解控释系统的起始材料。
