Deciphering the scaling of single-molecule interactions using Jarzynski's equality
Deciphering the scaling of single-molecule interactions using Jarzynski's equality
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DOI：
10.1038/ncomms6539
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发表时间：
2014-11-01
影响因子：
16.6
通讯作者：
Valtiner, Markus
中科院分区：
文献类型：
--
作者：
Raman, Sangeetha;Utzig, Thomas;Valtiner, Markus
解开宏观世界的复杂性依赖于理解单分子相互作用向整体宏观相互作用的比例。在这里，我们通过结合宏观表面力装置实验和单分子力谱的协同实验方法来演示单酸-胺相互作用的尺度。这个实验框架非常适合测试著名的雅金斯基等式，该等式将在非平衡条件下所做的功与平衡自由能联系起来。宏观平衡测量结果与界面键数密度成线性关系，酸胺相互作用能为10.9+/-0.2kT。无论单分子实验离平衡态有多远，雅金斯基的自由能都会收敛到11+/-1kT。我们的结果验证了Jarzynski等式的适用性，以揭示非平衡单分子实验在大量分子在平衡时同时相互作用的场景中的比例。开发的缩放策略在单分子测量的基础上预测大规模性质，如粘附性或细胞与细胞的相互作用。
Unravelling the complexity of the macroscopic world relies on understanding the scaling of single-molecule interactions towards integral macroscopic interactions. Here, we demonstrate the scaling of single acid-amine interactions through a synergistic experimental approach combining macroscopic surface forces apparatus experiments and single-molecule force spectroscopy. This experimental framework is ideal for testing the well-renowned Jarzynski's equality, which relates work performed under non-equilibrium conditions with equilibrium free energy. Macroscopic equilibrium measurements scale linearly with the number density of interfacial bonds, providing acid-amine interaction energies of 10.9 +/- 0.2 kT. Irrespective of how far from equilibrium single-molecule experiments are performed, the Jarzynski's free energy converges to 11 +/- 1 kT. Our results validate the applicability of Jarzynski's equality to unravel the scaling of non-equilibrium single-molecule experiments to scenarios where large numbers of molecules interacts simultaneously in equilibrium. The developed scaling strategy predicts large-scale properties such as adhesion or cell-cell interactions on the basis of single-molecule measurements.