Poly(N-isopropylacrylamide-co-Poly(ethylene glycol))-acrylate simultaneously physically and chemically gelling polymer systems
Poly(N-isopropylacrylamide-co-Poly(ethylene glycol))-acrylate simultaneously physically and chemically gelling polymer systems
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DOI：
10.1002/app.26760
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发表时间：
2007-10-15
影响因子：
3
通讯作者：
Vernon, Brent L.
中科院分区：
文献类型：
--
作者：
Cheng, Vicki;Lee, Bae Hoon;Vernon, Brent L.
在努力创建用于体内应用的原位物理和化学交联的水凝胶中，N-异丙基丙烯酰胺（NIPAAm）与聚（乙二醇）-单丙烯酸酯（PEG-单丙烯酸酯）共聚，然后用丙烯酰氯进一步修饰PEG的羟基末端以形成具有丙烯酸酯封端的侧基的聚（NI-PAAm-co-PEG）。除了随温度变化而物理胶凝之外，当在pH 7.4的磷酸盐缓冲盐水溶液中与多硫醇化合物如季戊四醇四（3-巯基丙酸酯）（QT）混合时，该聚合物通过迈克尔型加成反应形成化学凝胶。聚合物的化学凝胶化时间受混合时间的影响;共聚物溶液的溶胀是温度依赖性的。由于其独特的凝胶化特性，这种材料可能比其他热敏物理凝胶更适合长期功能替代应用。此外，该材料的PEG含量可以使其比先前同时化学和物理胶凝材料中的类似的基于HEMA的前体更具生物相容性。由于其机械强度和生物相容性的改善，该材料有可能作为热凝胶可注射生物材料应用于动脉瘤或动静脉畸形（AVM）闭塞。(C)2007 Wiley Periodicals，Inc.
In an effort to create an in situ physically and chemically cross-linked hydrogel for in vivo applications, N-isopropylacrylamide (NIPAAm) was copolymerized with poly(ethylene glycol)-monoacrylate (PEG-monoacrylate) and then the hydroxyl terminus of the PEG was further modified with acryloyl chloride to form poly(NI-PAAm-co-PEG) with acrylate terminated pendant groups. In addition to physically gelling with temperature changes, when mixed with a multi-thiol compound such as pentaerythritol tetrakis 3-mercaptopropionate (QT) in phosphate buffer saline solution of pH 7.4, this polymer formed a chemical gel via a Michael-type addition reaction. The chemical gelation time of the polymer was affected by mixing time; swelling of the copolymer solutions was temperature dependant. Because of its unique gelation properties, this material may be better suited for long-term functional replacement applications than other thermo-sensitive physical gels. Also, the PEG content of this material may render it more biocompatible than similar HEMA-based precursors in previous simultaneous chemically and physically gelling materials. With its improved mechanical strength and biocompatibility, this material could potentially be applied as a thermally gelling injectable biomaterial for aneurysm or arteriovenous malformation (AVM) occlusion. (C) 2007 Wiley Periodicals, Inc.