一个设计用于在水中的pH可切换离子结合的受体
Stephen G Tajc1, Benjamin L Miller
1Department of Biochemistry and Biophysics, University of Rochester, New York 14642, USA.
Journal of the American Chemical Society
|February 24, 2006
概括
研究人员开发了一种具有pH值可切换性质的新型分子. 这种受体在高pH值时结合离子,显示出化学传感应用的潜力.
科学领域:
- 超分子化学 超分子化学
- 化学传感器 化学传感器
- 分子识别分子识别
背景情况:
- 具有可切换性质的分子对于化学传感等应用至关重要.
- 键是设计响应分子的关键结构元素.
- 了解pH值依赖的构造变化对于分子设计至关重要.
研究的目的:
- 合成一种具有pH可切换的形状性质的新型受体分子.
- 为了研究胺化合物在控制分子构成中的作用.
- 评估该分子作为依赖pH值的离子受体的潜力.
主要方法:
- 通过对环素1,3,5-三甲醇与氨酸的 peracylation 合成一种新型受体.
- 核磁共振 (NMR) 光谱,包括质子纵向放松率和NOESY实验,以评估pH依赖的构造变化.
- 紫外线定位和异热定位热量测量 (ITC) 用于研究离子和阴离子结合.
主要成果:
- 合成的受体表现出质子纵向放松率的pH依赖性变化,与相关结构不同.
- NOESY光谱显示了pH值的显著变化,表明pH值诱导的形转换到pH值9.5.5的"关闭"状态.
- 该分子在高pH值下在水溶液中显示出阳离子和阳离子的选择性结合,但在低pH值下却没有.
结论:
- 胺-胺键是一种有效的结构图案,用于创建可切换pH的分子构造.
- 新型受体显示有条件结合特性,仅在更高的pH值下作为离子受体起作用.
- 这项工作为设计用于pH控制化学传感和分子识别的先进分子提供了基础.
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