Kang Yunqing, Yin Guangfu, Ouyang Ping, Huang Zhongbing, Yao Yadong, Liao Xiaoming, Chen Aizheng, Pu Ximing
College of Materials Science and Engineering, Sichuan University, Chengdu, Sichuan 610064, China.
J Colloid Interface Sci. 2008 Jun 1;322(1):87-94. doi: 10.1016/j.jcis.2008.02.031. Epub 2008 Apr 9.
In this work, poly(L-lactic acid)/poly(lactide-co-glycolide) (PLLA/PLGA) microparticles were prepared using the technique of solution-enhanced dispersion by supercritical fluids (SEDS). For comparison, separate PLLA and PLGA microparticles were also produced by the same SEDS process. The produced microparticles were characterized by scanning electron microscopy, laser particle size analyzer, X-ray diffraction, differential scanning calorimetry, Fourier transform infrared spectroscopy, and gas chromatography. Results indicate that PLLA/PLGA microparticles possess sphere-like shapes with smooth surfaces. The mean particle size of PLLA/PLGA microparticles ranges from 1.76 to 2.15 microm, depending on the feeding ratio of PLLA to PLGA used in the SEDS process. The crystallinity of PLLA/PLGA microparticles decreases after the SEDS processing, so that the produced microparticles are in an amorphous state. Pure PLGA was hard to precipitate in small, fine microparticle form without the presence of PLLA. A model drug, paclitaxel, was encapsulated into PLLA/PLGA microparticles by the same SEDS process, and the in vitro release rate of paclitaxel from these PLLA/PLGA composites could be modulated by variation of the mixing ratio PLLA:PLGA. The prepared microparticles have negligible residual organic solvent. Drug-loaded PLLA/PLGA microparticles produced by SEDS have potential as an advanced colloidal suspension for pharmaceutical applications.
在本研究中,采用超临界流体增强溶液分散技术(SEDS)制备了聚(L-乳酸)/聚(丙交酯-乙交酯)(PLLA/PLGA)微粒。为作比较,还通过相同的SEDS工艺分别制备了PLLA和PLGA微粒。通过扫描电子显微镜、激光粒度分析仪、X射线衍射、差示扫描量热法、傅里叶变换红外光谱和气相色谱对所制备的微粒进行了表征。结果表明,PLLA/PLGA微粒呈表面光滑的球形。PLLA/PLGA微粒的平均粒径在1.76至2.15微米之间,这取决于SEDS工艺中使用的PLLA与PLGA的进料比。经过SEDS处理后,PLLA/PLGA微粒的结晶度降低,因此所制备的微粒处于非晶态。在没有PLLA存在的情况下,纯PLGA很难以细小的微粒形式沉淀。采用相同的SEDS工艺将模型药物紫杉醇包封到PLLA/PLGA微粒中,通过改变PLLA:PLGA的混合比例可以调节紫杉醇从这些PLLA/PLGA复合材料中的体外释放速率。所制备的微粒残留有机溶剂可忽略不计。通过SEDS制备的载药PLLA/PLGA微粒具有作为药物应用的先进胶体悬浮液的潜力。