新型温敏羟丙基纤维素微凝胶的合成  

SYNTHESIS OF NEW THERMOSENSITIVE MICROGEL FROM HYDROXYPROPYL CELLULOSE

作　　者：吕丹崖[1] 王润雨[1] 关英[1] 张拥军[1] 

机构地区：[1]南开大学化学学院高分子化学研究所,功能高分子材料教育部重点实验室,天津300071

出　　处：《离子交换与吸附》2012年第2期97-103,共7页Ion Exchange and Adsorption

基　　金：南开大学本科生创新科研项目(BX8-066);天津市科技计划项目(10JCYBJC02000);科技部国际科技合作项目(2007DFA50760)

摘　　要：天然高分子具有良好的生物相容性和生物可降解性,因此用天然高分子制备的微凝胶更适合于生物医学领域的应用。羟丙基纤维素(HPC)是一种具有温度敏感性的纤维素衍生物,可通过不同的方法制备为微凝胶,然而现有方法制备的HPC微凝胶都不能完全降解。我们采用一种新方法制备HPC微凝胶。首先通过NaIO4处理将醛基引入HPC。红外光谱检测证明了醛基的生成。氧化后的HPC仍具温敏性,其最低临界溶解温度(LCST)保持不变;当加热到LCST以上时,HPC分子通过疏水相互作用聚集成纳米小球;再加入交联剂己二酸二酰肼,通过醛基与胺基之间的反应,使纳米小球共价交联得到HPC微凝胶。电镜研究表明HPC微凝胶呈球形,粒径在100～300nm之间。浊度和光散射研究表明HPC微凝胶仍具温敏性。细胞毒性实验表明我们制备的微凝胶几乎没有细胞毒性。由于HPC及交联剂己二酸二酰肼均可生物降解,预期我们制备的微凝胶也能很好地降解,并有望应用于生物医学领域。Due to their better biocompatibility and biodegradability, microgels from natural polymers are preferable for applications in biomedical areas. Microgels have been synthesized from hydroxypropylcellulose （HPC）, a thermosensitive cellulose ether, via various methods, however, none of the resultant products can be degraded completely, posing barriers for in vivo applications. Here a new method was developed to synthesize HPC microgel. HPC was first partially oxidized with sodium periodate to generate aldehyde functionalities. The introduction of aldehyde groups was confirmed by FTIR spectra. The oxidized HPC remains thermosensitive and its lower critical solution temperature （LCST） remained unchanged. When heated above the LCST, HPC chains aggregated into nanoparticles through hydrophobic interaction. The nanoparticles were then covalently crosslinked with adipic dihydrazide, as a result of the reaction between the aldehyde groups in HPC and the amino groups in the crosslinker. TEM study showed the microgel particles were round in shape with a size ranging from 100nm to 300rim. The microgel was thermosensitive, as indicated by its shrunken size and increased turbidity upon heating. Preliminary in vitro cytotoxicity assay showed no changes in cell viability and morphology in the presence of HPC microgel, suggesting the microgel synthesized here was not cytotoxinic. As both HPC and adipic dihydrazide were biodegradable, the new microgel was also expected to be biodegradable and may find applications in biomedical areas.

关 键 词：微凝胶 羟丙基纤维素 交联 温度敏感 

分 类 号：O648.17[理学—物理化学]