一个bis ((adamantyl) 功能化的[4]arene与基于β-cyclodextrin的主体的双价结合:在溶液和自组装单层中对多价结合的实验和理论研究
Alart Mulder1, Tommaso Auletta, Andrea Sartori
1Laboratory of Supramolecular Chemistry & Technology, MESA Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
Journal of the American Chemical Society
|May 27, 2004
概括
一种bis ((adamantyl) 功能化的[4]arene与β-cyclodextrin二元体的结合在黄金表面上明显强于溶液中. 这种差异是由专注于有效度效应的理论模型解释的.
科学领域:
- 超分子化学 超分子化学
- 主机和客人的化学反应
- 表面化学 表面化学
背景情况:
- [4]和环极 (CDs) 是成熟的宿主分子.
- 双胺基) 功能化[4]烯 (1) 和EDTA结合的β-环极素 (CD) 二次体 (2) 设计用于宿主-客人相互作用.
- 了解不同环境中的结合亲和关系对于分子识别应用至关重要.
研究的目的:
- 量化和比较Calix[4]arene 1对溶液中的CD二极体2的双价结合亲和力,与金上的自组装单层 (SAM) 相比.
- 开发和应用一个理论模型来合理化约束常数中观察到的差异.
- 阐明有助于增强表面结合的因素.
主要方法:
- 基于溶液的结合性研究,以确定1和2之间的相互作用的关联常数.
- 表面等离子共振 (SPR) 或类似的技术来测量1与CD SAMs在黄金上的结合.
- 开发一种理论模型,将双价结合解释为连续的单价事件.
主要成果:
- 溶液中的结合常数 (1.2 x 10^7 M^-1) 比在黄金上的CD SAM上 (约. 10^10 M^-1) 的数量.
- 一个理论模型成功地通过考虑两个连续的单价结合事件来合理化结合数据.
- 该模型强调了"有效度"术语对表面内分子结合的重要作用.
结论:
- 与溶液相比,双向宿主-客串结合在表面上显著增强.
- 对表面的增强结合主要归因于由于分子运动受到限制,有效度更高.
- 该理论框架为理解和预测各种超分子系统中的结合亲和关系提供了有价值的工具.
相关概念视频
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