在高电荷的双块联聚合物水凝中,盐的稳定性异常
Andrew P Nowak1, Victor Breedveld, David J Pine
1Departments of Materials and Chemistry, Materials Research Laboratory, University of California, Santa Barbara, CA 93106, USA.
Journal of the American Chemical Society
|December 11, 2003
概括
研究人员从氨基酸N-碳素化物 (NCAs) 开发了新的水凝,这些水凝在各种离子条件下保持稳定. 这些两性共聚合物显示出作为组织再生应用的支架的前景.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 生物医学工程 生物医学工程
背景情况:
- 通过过渡金属介导的氨基酸N-碳素化物 (NCAs) 聚合合成的稀释溶液水凝是两性双块共聚物.
- 这些水凝由含水性,带电的部分 (多聚氨酸HBr) 或多聚氨酸盐) 和疏水螺旋部分 (多聚氨酸) 组成.
研究的目的:
- 研究这些水凝在脱离离子水和各种离子介质中的稳定性和性能.
- 优化共聚合物组成和分子量,以提高水凝强度和可溶性,在各种溶液中.
主要方法:
- 使用氨基酸NCAs的过渡金属介导聚合物合成二块两共聚合物的合成.
- 在脱离离子水,盐溶液 (高达0.5M NaCl),细胞生长介质和不同pH的缓冲剂中,水凝稳定性和性能的表征.
- 调整相对的共聚合物组成和分子量,以达到所需的水凝性能.
主要成果:
- 在低聚合物度 (0.25 wt %) 的脱离离子水中,水凝形成强的凝.
- 在盐或缓冲溶液中的稳定性需要中等较高的聚合物度 (约. 3.0重量百分比).
- 水凝在高离子强度介质中表现出独特的稳定性,而不会崩,尽管它依赖充电的多电解质部分进行凝.
结论:
- 这些新的水凝在各种离子条件下表现出了显著的稳定性.
- 它们的独特特性使得它们非常适合生物医学应用,特别是作为组织再生的支架.
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