脂双细胞与它们的正常水平平行于磁场的平行线,与磁场平行线对齐
Chibing Tan1, B M Fung, Gyoujin Cho
1Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019-3051, USA.
Journal of the American Chemical Society
|September 26, 2002
概括
与DBBPC和DHPC形成的新型脂双细胞 (双层小细胞) 在磁场中对齐. 这些双细胞表现出明显的头组构造和相位行为,在更高的温度下与同位素微细胞共存.
科学领域:
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
- 生物物理学的生物物理.
背景情况:
- 脂双细胞是双层状结构,用于各种应用.
- 之前的研究报告了具有阳性磁感性异性质的双细胞.
- 双细胞合成的改进对于先进的应用至关重要.
研究的目的:
- 为了合成和表征一种新的脂,DBBPC.
- 研究由DBBPC和DHPC组成的双细胞的形成和特性.
- 探索这些新双细胞在磁场中的相位行为和对齐.
主要方法:
- 合成的1-多德卡诺伊尔-2-(4-(4-双) 布他诺伊尔) -sn-糖-3-胆 (DBBPC).
- 通过在特定比例中将DBBPC与DHPC混合,形成双细胞.
- 核磁共振 (NMR) 光谱学 ((31) P, (2) H, (23) Na, (1) H-(13) C) 用于表征和阶段行为分析.
- 磁场对齐研究.磁场对齐研究.
主要成果:
- 在水性介质中,DBBPC/DHPC双细胞在定义的比例 (5.1:1到6.5:1) 中成功形成.
- (31) P NMR 证实了在广泛的温度范围内,双细胞与主要轴平行于磁场的对齐.
- 阶段行为研究揭示了从双细胞阶段过渡到在更高温度 (54-75°C) 上与同位素菌共存.
- 通过 (31) P的化学变化,可以推测出不同的极地头组构造.
- 观察到马尔托里奥斯的部分对齐,并分析了 (1) H- ((13) C双极合常量.
结论:
- 新的DBBPC/DHPC双在磁场中表现出稳定的对齐.
- 这些双细胞表现出独特的相位行为,在升高的温度下转变为同otropic micelles.
- 这些发现有助于理解NMR和材料科学中的潜在应用的双细胞结构,动力学和磁对齐特性.
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