Poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)/poly(ε-caprolactone) (PCL) amphiphilic block copolymeric nanospheres -: II.: Thermo-responsive drug release behaviors
Poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)/poly(ε-caprolactone) (PCL) amphiphilic block copolymeric nanospheres -: II.: Thermo-responsive drug release behaviors
复制标题
DOI：
10.1016/s0168-3659(99)00207-2
复制
发表时间：
2000-04-03
影响因子：
10.8
通讯作者：
Lee, YM
中科院分区：
文献类型：
--
作者：
Kim, SY;Ha, JC;Lee, YM
在PEO-PPO-PEO嵌段共聚物存在下，以辛酸亚锡为催化剂，通过ε-己内酯开环聚合，合成了由相对亲水的PEO-PPO-PEO嵌段共聚物（Pluronic）和具有疏水性的聚ε-己内酯组成的两亲性嵌段共聚物。采用透析法制备了具有核壳结构的Pluronic/PCL嵌段共聚物纳米微球。根据共聚物的类型，它们显示出116-196 nm的平均直径。所有的纳米球样品表现出窄的尺寸分布。荧光光谱法测定的Pluronic/PCL两亲性嵌段共聚物的临界胶束浓度低于普通低分子表面活性剂的临界胶束浓度。通过核磁共振氢谱证实了它们的核壳结构。Pluronic/PCL嵌段共聚物纳米微球的尺寸随温度的变化呈现可逆性变化。吲哚美辛从Pluronic/PCL嵌段共聚物纳米球中的释放行为也表现出温度依赖性和缓释模式。MTT法细胞毒性实验结果表明，与未负载吲哚美辛相比，负载吲哚美辛的Pluronic/PCL纳米微球可显著减轻细胞损伤。(C)2000 Elsevier Science B. V.保留所有权利。
Amphiphilic block copolymers composed of relatively hydrophilic PEO-PPO-PEO block copolymer (Pluronic) and poly(epsilon-caprolactone) with hydrophobic character were synthesized by ring-opening polymerization of epsilon-caprolactone in the presence of PEO-PPO-PEO block copolymer using stannous octoate as a catalyst. Pluronic/PCL block copolymeric nanospheres with core-shell structure were prepared by dialysis method. They showed the average diameter of 116-196 nm depending on the type of copolymer. All the nanosphere samples exhibited a narrow size distribution. The critical micelle concentrations of Pluronic/PCL amphiphilic block copolymers determined by fluorescence spectroscopy were lower than that of the common low molecular weight surfactant. Their core-shell structure was confirmed by H-1 NMR spectroscopy. Pluronic/PCL block copolymeric nanospheres exhibited the reversible change of size depending on the temperature. Release behaviors of indomethacin from Pluronic/PCL block copolymeric nanospheres also showed temperature dependence and a sustained release pattern. In addition, cytotoxicity test using an MTT assay method revealed that these indomethacin-loaded Pluronic/PCL nanospheres could remarkably reduce the cell damage compared with the unloaded free indomethacin. (C) 2000 Elsevier Science B.V. All rights reserved.