Synthesis and characterization of novel thermo-responsive F68 block copolymers with cell-adhesive RGD peptide
Synthesis and characterization of novel thermo-responsive F68 block copolymers with cell-adhesive RGD peptide
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DOI：
10.1016/j.jcis.2011.04.041
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发表时间：
2011-08-01
影响因子：
9.9
通讯作者：
Han, Dong Keun
中科院分区：
文献类型：
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作者：
Cha, Myoung-Hwa;Choi, Jiyeon;Han, Dong Keun
合成了含疏水基团、低聚乳酸(寡乳酸)或低聚己内酯(低聚己内酯)、2-甲基和RGD为侧基的热敏性聚氧乙烷-聚环氧丙烷-聚环氧乙烷(PEO-PPO-PEO)三嵌段共聚物Pluronic F68，并用核磁共振、红外光谱和元素分析对其进行了表征。当聚合物浓度高于临界胶束浓度(CMC)时，随着温度从10℃升高到70℃，它们的水溶液表现出特殊的凝胶-溶胶-凝胶相变行为。用倒管法、流变仪和动态光散射法研究了凝胶-溶胶相图。在此基础上，考察了取代基组成、低聚L-LA或低聚β-CL的链长、聚合物溶液浓度等因素对改性F68凝胶性能的影响。由PPO嵌段核和PEO嵌段壳组成的改性F68三嵌段共聚物在水溶液中观察到了独特的温度相变行为。用核磁共振氢谱数据解释了这一现象；疏水相互作用和链运动性的改变导致了透明凝胶的形成，凝胶-溶胶共存，以及不透明凝胶。这些水凝胶可能在药物输送和组织工程中有用。(C)2011 Elsevier Inc.保留所有权利。
Thermosensitive poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymer, Pluronic F68, containing a hydrophobic unit, oligo-(lactic acid)(oligo-LA) or oligo-caprolactone (oligo-CL), 2-META and RGD as side groups was successfully synthesized and characterized by H-1 NMR, FTIR, and elemental analysis. Their aqueous solution displayed special gel-sol-gel phase transition behavior with increasing temperature from 10 to 70 degrees C, when the polymer concentration was above critical micelle concentration (CMC). The gel-sol phase diagram was investigated using tube inversion method, rheological measurement, and dynamic light scattering. Based on these results, the gelation properties of modified F68 were affected by several factors such as the composition of the substituents, chain length of oligo L-LA or oligo epsilon-CL, and the concentration of the polymer solutions. The unique phase transition behavior with temperature was observed by modified F68 triblock copolymer, composed of the PPO blocks core and the PEO blocks shell in aqueous solution. This phenomenon was elucidated using H-1 NMR data; the alteration of hydrophobic interaction and chain mobility led to the formation of transparent gel, coexistence of gel-sol, and opaque gel. These hydrogels may be useful in drug delivery and tissue engineering. (C) 2011 Elsevier Inc. All rights reserved.