The noise is the signal: exploring physico-chemical fluctuations with multiscale experimental models

噪音就是信号：用多尺度实验模型探索物理化学波动

• 批准号: EP/X02492X/1
• 负责人: Alice Thorneywork
• 金额: $ 157.28万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FX02492X%2F1
• 关键词: noise; signal; exploring; physico; chemical

Noise is a universal aspect of experimental science, usually considered detrimental. Yet fluctuations contain significant information, as famously proposed by Onsager. Such links between microscopic fluctuations and macroscopic transport are heavily exploited by simulation studies, but their relevance to physico-chemical experiments is only now emerging as data at the single-particle level becomes available. While many important transport phenomena are amenable to fluctuation analysis, interpreting data from molecular experiments is extremely challenging, due to the short time and length scales and inherent complexity of these systems. This project aims to uncover the origins of physico-chemical noise, and thereby develop the tools required to extract and interpret microscopic information from molecular data, by exploring fluctuations in a unique combination of highly controlled mesoscale and nanoscale experimental models that can be driven out of equilibrium. I will first consider how confinement and interactions modify fluctuations in currents of colloidal particles driven through microfluidic channels. Quantifying fluctuations via direct observation of trajectories and calculation of the power spectral density will allow me to address long-standing questions surrounding 'coloured' noise signatures. Secondly, I will use flexible, model polymers to probe the complex interplay between conformational fluctuations, entropy and hydrodynamic interactions that modulate confined polymer transport. Finally, I will build on these findings to study, analyse and interpret fluctuations in the ionic currents associated with transport through flexible DNA nanostructures. My combined results will provide unprecedented insights into physico-chemical noise at a fundamental level, while the analysis tools developed will facilitate research into diverse phenomena; from transport through biological membranes, to flow in lab-on-a-chip devices and sensing with functionalised nanopores.

噪声是实验科学的一个普遍方面，通常被认为是有害的。然而，正如Onsager著名的提议那样，波动包含着重要的信息。微观波动和宏观输运之间的这种联系被模拟研究大量利用，但它们与物理化学实验的相关性直到现在才随着单粒子水平的数据变得可用而出现。虽然许多重要的输运现象适合于涨落分析，但由于这些系统的短时间和短长度尺度以及固有的复杂性，解释来自分子实验的数据是非常具有挑战性的。该项目旨在揭示物理化学噪声的起源，从而开发从分子数据中提取和解释微观信息所需的工具，方法是探索高度受控的中尺度和纳米尺度实验模型的独特组合中的波动，这些模型可以打破平衡。我将首先考虑限制和相互作用如何改变通过微流控通道驱动的胶体颗粒电流的波动。通过直接观察运动轨迹和计算功率谱密度来量化波动，将使我能够解决围绕“有色”噪声特征的长期存在的问题。其次，我将使用灵活的模型聚合物来探索构象波动、熵和流体动力相互作用之间的复杂相互作用，这些相互作用调节受限的聚合物运输。最后，我将在这些发现的基础上，研究、分析和解释与柔性DNA纳米结构传输相关的离子电流的波动。我的综合结果将在基本层面上提供对物理化学噪声的前所未有的洞察，而开发的分析工具将促进对各种现象的研究；从通过生物膜的传输，到流入芯片实验室设备，以及使用功能化纳米孔进行传感。