School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore.
J Control Release. 2011 May 10;151(3):229-38. doi: 10.1016/j.jconrel.2011.02.012. Epub 2011 Feb 23.
Double-layered ternary-phase microparticles composed of a poly(D,L-lactide-co-glycolide) (50:50) (PLGA) core and a poly(L-lactide) (PLLA) shell impregnated with poly(caprolactone) (PCL) particulates were loaded with ibuprofen (IBU) and metoclopramide HCl (MCA) through a one-step fabrication process. MCA and IBU were localized in the PLGA core and in the shell, respectively. The aim of this study was to study the drug release profiles of these double-layered ternary-phase microparticles in comparison to binary-phase PLLA(shell)/PLGA(core) microparticles and neat microparticles. The particle morphologies, configurations and drug distributions were determined using scanning electron microscopy (SEM) and Raman mapping. The presence of PCL in the PLLA shell gave rise to an intermediate release rate of MCA between that of neat and binary-phase microparticles. The ternary-phase microparticles were also shown to have better controlled release of IBU than binary-phase microparticles. The drug release rates for MCA and IBU could be altered by changing the polymer mass ratios. Ternary-phase microparticles, therefore, provide more degrees of freedom in preparing microparticles with a variety of release profiles and kinetics.
双层三元相微球由聚（D，L-丙交酯-共-乙交酯）（50：50）（PLGA）核和聚（L-丙交酯）（PLLA）壳组成，壳中浸渍有聚己内酯（PCL）颗粒，通过一步法制备过程载入布洛芬（IBU）和盐酸甲氧氯普胺（MCA）。MCA 和 IBU 分别定位在 PLGA 核和壳中。本研究的目的是研究这些双层三元相微球与二元相 PLLA（壳）/PLGA（核）微球和纯微球的药物释放曲线。使用扫描电子显微镜（SEM）和拉曼映射来确定颗粒形态、结构和药物分布。PLLA 壳中存在 PCL 导致 MCA 的释放速率介于纯微球和二元相微球之间。还表明，三元相微球比二元相微球具有更好的 IBU 控制释放。通过改变聚合物质量比可以改变 MCA 和 IBU 的药物释放速率。因此，三元相微球在制备具有各种释放曲线和动力学特性的微球方面提供了更多的自由度。
