Effects of the rate of solvent evaporation on the characteristics of drug loaded PLLA and PDLLA microspheres
Effects of the rate of solvent evaporation on the characteristics of drug loaded PLLA and PDLLA microspheres
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DOI：
10.1016/s0378-5173(00)00574-3
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发表时间：
2001-01-16
影响因子：
5.8
通讯作者：
Liu, YZ
中科院分区：
文献类型：
--
作者：
Chung, TW;Huang, YY;Liu, YZ
研究了固定温度下不同环境压力下溶剂去除率对负载利多卡因的聚-l -乳酸酯（PLLA）和聚- d -l -乳酸酯（PDLLA）微球形貌、粒径、药物包封效率和释放模式的影响。采用快速溶剂蒸发法（FRSE）降低环境压力制备了载药PLLA和PDLLA微球，观察到微球表面光滑。而在正常溶剂蒸发（NRSE）过程中，只有载药PLLA微球表面出现了粗糙度或针孔。与NRSE工艺相比，FRSE工艺制备的PLLA和PDLLA微球粒径更小，药物包封效率更低。在两种材料中，PLLA微球的包封效率均高于pdla微球。尽管无论何种溶剂去除工艺制备的PLLA微球和PDLLA微球都有药物的初始爆发释放，但在药物释放的早期阶段，PLLA微球的药物释放量略低于PDLLA微球。然而，在随后的药物释放阶段，两种材料之间没有差异。结合PLA聚合物及其衍生物的不同结晶特性，可以进一步采用降低环境压力的FRSE工艺制备不同特性的给药微球。(C) 2001 Elsevier Science B.V.版权所有
We investigated the effects of the rate of solvent removal by varying ambient pressure at a fixed temperature on the morphology, particle sizes, drug encapsulation efficiency and releases pattern of lidocaine loaded poly-L-lactatide (PLLA) and poly-D,L-lactatide (PDLLA) microspheres, prepared with O/W emulsion-solvent evaporation process. Prepared in the fast rate of solvent evaporation (FRSE) process by reducing ambient pressure, smoothly morphological surface of drug loaded PLLA and PDLLA microspheres was observed. While in the normal rate of solvent evaporation (NRSE) process, roughness or pinhole surface was only found at drug loaded PLLA microspheres. Fabricated in the FRSE process, both PLLA and PDLLA microspheres showed smaller particle sizes and lower drug encapsulation efficiencies than those prepared in NRSE process. In regard to two materials, PLLA microspheres had higher drug encapsulation efficiencies than PDLLA ones for both processes. Although initial burst releases of drug were observed for both PLLA and PDLLA microspheres prepared in whatever solvent removal process, drug release for PLLA microspheres was slightly less than that for PDLLA ones in the earlier stage of drug release. However, in the subsequent stage of drug release, there was no difference between two materials. In corporation with different crystalline characteristics of PLA polymer and its derivatives, FRSE process by reducing ambient pressure could be further applied to produce different characteristics of microspheres for drug delivery. (C) 2001 Elsevier Science B.V. All rights reserved.