灾难性Xe化学转移在绑定的加密子子中发生
E Janette Ruiz1, Devin N Sears, Alexander Pines
1Department of Chemistry, University of California at Berkeley, Berkeley, CA 94720, USA.
Journal of the American Chemical Society
|December 21, 2006
概括
通过使用性分子来使加密细胞具功能,使得-133 (Xe) 能够作为生物传感器. 这项研究使用量子力学来预测Xe NMR信号,有助于从奇拉替代物分配复杂的光谱.
科学领域:
- 超分子化学 超分子化学
- 计算化学计算化学
- 核磁共振光谱法 核磁共振光谱法
背景情况:
- 加密子囊封装了像 (Xe) 这样的原子,使得基于 Xe 的生物传感等应用成为可能.
- 合成的密码常常会产生种族混合物,使分析复杂化.
- 在加密子上的基拉尔替代剂会影响封装Xe的NMR信号.
研究的目的:
- 通过计算来研究合替代剂对Xe NMR信号在功能化的加密-A中的影响.
- 为了预测 diastereomeric cryptophane 系统中封装 Xe 的化学转移.
- 提供一种用于分配复杂的Xe NMR光谱的方法,而不需要对酶体纯合成.
主要方法:
- 量子力学计算Xe核磁屏蔽的量子力学计算.
- 模型化潜能代表外的"r"或"l"替代物.
- 计算Xe屏蔽响应对各种异构体加密-L替代剂组合.
主要成果:
- 计算预测了基于替代品中的性和不对称中心数量的Xe NMR信号分裂模式.
- 可以预测Xe化学转移在二聚体溶液中的相对顺序 (例如,Rl与Ll).
- 该研究表明,基于计算的屏蔽反应,能够在实验性XE NMR光谱中赋予峰值.
结论:
- 在奇拉加密系统中Xe屏蔽的计算建模为光谱分配提供了强大的工具.
- 这种方法简化了用于生物传感器开发的功能化密码体的表征.
- 这些发现促进了 Xe NMR 的使用,用于分析复杂的性超分子系统.
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