Detection of diffusion anisotropy due to particle asymmetry from single-particle tracking of Brownian motion by the large-deviation principle
Detection of diffusion anisotropy due to particle asymmetry from single-particle tracking of Brownian motion by the large-deviation principle
复制标题
DOI：
10.1103/physreve.85.051134
复制
发表时间：
2012-05-25
影响因子：
2.4
通讯作者：
Isono, Yoshitada
中科院分区：
文献类型：
--
作者：
Hanasaki, Itsuo;Isono, Yoshitada
我们表明，由于粒子的不对称性的扩散各向异性可以从轨迹数据中提取的粒子取向的信息。分析的对象是单粒子跟踪实验中的典型问题，分析的基础是数学中的大偏差原理。我们考虑的模型系统的Langevin方程在两个维度的颗粒扩散显示各向异性取决于一个单一的参数定义的两个扩散系数在垂直方向的框架固定到粒子。我们展示了大偏差量如何依赖于这个参数，以便它可以用于检测的扩散各向异性。我们还说明了如何在SPT和有限的样本数量的抽样间隔的离散性影响的分析结果。
We show that the diffusion anisotropy due to the asymmetry of the particle can be extracted from the trajectory data without the information of the particle orientation. The subject of analysis is typical in single-particle tracking (SPT) experiments, and the analysis is based on the large-deviation principle in mathematics. We consider the model system of Langevin equations in two dimensions where a particle diffusion shows anisotropy depending on a single parameter defined by the two diffusion coefficients in the perpendicular directions of the frame fixed to the particle. We show how the large-deviation quantities depend on this parameter so that it can be used for the detection of the diffusion anisotropy. We also illustrate how the discreteness of the sampling interval in the SPT and the finiteness of the number of samples influence the results of the analysis.