用AFM力光谱测量水中的线性基之间的对交互
Chad Ray1, Jason R Brown, Andrea Kirkpatrick
1Department of Chemistry, Duke University, Durham, North Carolina 27708, USA.
Journal of the American Chemical Society
|July 4, 2008
概括
单分子力谱学揭示了水中的n-alkane相互作用. 一个双键断裂模型准确地描述了断裂力,表明基因在二元化时崩,影响菌形成.
科学领域:
- 物理化学 物理化学
- 生物物理学的生物物理.
- 表面科学是一门学科.
背景情况:
- 了解疏水性相互作用对于分子自我组装和生物过程至关重要.
- 以前的分子破裂力模型往往简化了纽带动力学.
- n-基作为研究水溶液中疏水效应的模型系统.
研究的目的:
- 通过单分子力光谱学研究水中的n-基 (十至十) 之间的双对相互作用.
- 开发和验证一个理论模型,准确地描述在这些相互作用中观察到的断裂力的分布.
- 探索二元化过程的热力学和动力学方面及其对疏水性相互作用的影响.
主要方法:
- 单分子力光谱法 (SMFS) 用于测量n-之间的断裂力.
- 分子被绑定到一个原子力显微镜探头和基板使用水溶性链接器.
- 分析模型考虑两个债券几乎同时破裂,并使用最可能的力分析来解释数据.
主要成果:
- 实验破裂力分布被一个具有一致动力参数的双键破裂模型描述得很好.
- 最可能的力分析产生了不同的参数,表明其在此应用的局限性.
- 对基解离的测量激活能与腔模型保持一致,但与链条长度不一致地增加.
- 确定了大约0.6nm的过渡状态屏障距离.
结论:
- 与更简单的模型相比,双键断裂模型提供了对水中的n-alkane相互作用的优越描述.
- 阿尔干二元化可能涉及到向崩状态的构造过渡,偏离了简单的扩展模型.
- 这种形状变化提供了关于表面活性剂微粒自我组装的动力学的见解.
相关概念视频
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