Choi Seung Ho, Lee Ji-Hwan, Choi Sung-Min, Park Tae Gwan
Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea.
Langmuir. 2006 Feb 14;22(4):1758-62. doi: 10.1021/la052549n.
Novel Pluronic/heparin composite nanocapsules that exhibit a thermally responsible swelling and deswelling behavior were synthesized. Pluronic F-127 preactivated with p-nitrophenyl chloroformate at its two terminal hydroxyl groups was dissolved in a methylene chloride phase. The organic phase was dispersed in an aqueous phase containing heparin. At an organic/aqueous interface, Pluronic-cross-linked heparin nanocapsules were produced. They exhibited a 1000-fold volume transition (ca. 336 nm at 25 degrees C; ca. 32 nm at 37 degrees C), and a reversible swelling and deswelling behavior when the temperature was cycled between 20 and 37 degrees C. The reversible volume transition of Pluronic nanocapsules was caused by micellization and demicellization of cross-linked Pluronic polymer chains within the nanocapsule structure in response to temperature. The morphological characters were investigated with transmission electron microscopy and small angle neutron scattering. Pluronic/heparin nanocapsules had an aqueous fluid-filled hollow interior with a surrounding shell layer below the critical temperature, but they became a collapsed core/shell structure similar to that of Pluronic micelles above it.
合成了具有热响应性溶胀和消溶胀行为的新型普朗尼克/肝素复合纳米胶囊。在其两个末端羟基用氯甲酸对硝基苯酯预活化的普朗尼克F - 127溶解于二氯甲烷相中。有机相分散于含有肝素的水相中。在有机/水界面处，生成了普朗尼克交联肝素纳米胶囊。它们表现出1000倍的体积转变（25℃时约为336nm；37℃时约为32nm），并且当温度在20℃和37℃之间循环时具有可逆的溶胀和消溶胀行为。普朗尼克纳米胶囊的可逆体积转变是由纳米胶囊结构内交联的普朗尼克聚合物链响应温度的胶束化和去胶束化引起的。用透射电子显微镜和小角中子散射研究了形态特征。普朗尼克/肝素纳米胶囊在临界温度以下具有充满水性流体的中空内部以及周围的壳层，但在临界温度以上它们变成了类似于普朗尼克胶束的塌陷核/壳结构。
