在离子介质中通过Nernst-Planck方程表述声电现象
Wei Yi Oon1, Yuchen Tang1, Wei-Ning Lee1,2
1Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong Special Administrative Region of China, People's Republic of China.
Physics in medicine and biology
|November 26, 2025
概括
这项研究引入了一个新的电动力学模型来模拟医疗超声波中的声电现象. 该模型预测了声电相互作用信号和液体连接电位,为超声诱导的电信号提供了更全面的理解.
科学领域:
- 生物物理学的生物物理.
- 医学超声波 医学超声波
- 计算电生理学 计算电生理学
背景情况:
- 声电 (AE) 现象,包括声电相互作用 (AEI),从声波中产生电场.
- 超声波诱导的AEI对刺激性组织的非侵入性电解剖学绘制有希望.
- 传统的AEI信号模拟是有限的,不能捕捉所有并发的AE现象.
研究的目的:
- 通过Nernst-Planck方程 (NPE) 使用离子介导电动学来模拟医学超声波中的AE现象.
- 开发一个有限元模型来计算基于NPE的AE效应.
- 为了更全面地了解实验测量的AE信号.
主要方法:
- 使用COMSOL®开发了一个有限元模型,以基于Nernst-Planck方程计算AE效应.
- 在具有混合离子组成的细胞外流体环境中模拟离子动力学.
- 导出了物种系数 (Q) 作为LJP振幅的离子依赖参数.
主要成果:
- 模拟揭示了两个电位元件:AEI信号和液结电位 (LJPs).
- 发现LJPs在特定的配置和弱电流密度下占主导地位,这对于解释实验AE信号至关重要.
- 模拟的信号幅度与各种角的实验数据有很好的一致性.
结论:
- 拟议的电动学模型准确计算了医学超声波中AE信号背后的离子动力学.
- 该模型预测了电流独立的LJP信号,增强了原始AE信号的解释.
- 这种方法为未来的声电研究和非侵入性组织绘图提供了潜在的指导.
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