Hall Damien, Foster Adam S
WPI Nano Life Science Institute, Kanazawa University, Kanazawa, Ishikawa 920-1164, Japan.
Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland.
Biophys Physicobiol. 2022 Apr 15;19:1-21. doi: 10.2142/biophysico.bppb-v19.0016. eCollection 2022.
High speed atomic force microscopy (HS-AFM) is, in principle, capable of yielding nanometer level detail about the surface of static structures. However, for highly dynamic samples HS-AFM may struggle with the correct feature assignment both within and between frames. Feature assignment in HS-AFM is dependent on (i) the intrinsic sampling rate, and (ii) the rate of internal redistribution of the sample. Whilst the first quantity (the sampling rate) is defined by the device parameters, the second quantity is frequently unknown, and is often the desired target of the measurement. This work examines how, even in the absence of gross cell morphological change, the rapid dynamics of living cell membranes, may impose an upper spatial limit to the frame-to-frame assignment of cell micro-topography and other related properties (such as local elasticity) whose motion may be described stochastically. Such a practical maximum may prove useful in the setup of HS-AFM experiments involving dynamic surfaces thereby facilitating selection of the most parsimonious relationship between observation size, image pixilation and sampling rates. To assist with performing the described calculations a graphical user interface-based software package called HS-AFM UGOKU is made freely available.
高速原子力显微镜（HS-AFM）原则上能够提供有关静态结构表面的纳米级细节。然而，对于高度动态的样本，HS-AFM在帧内和帧间的正确特征分配方面可能会遇到困难。HS-AFM中的特征分配取决于（i）固有采样率，以及（ii）样本的内部重新分布速率。虽然第一个量（采样率）由设备参数定义，但第二个量通常是未知的，并且常常是测量的期望目标。这项工作研究了即使在没有明显细胞形态变化的情况下，活细胞膜的快速动态变化如何可能对细胞微观形貌和其他相关特性（如局部弹性）的逐帧分配施加空间上限，其运动可能是随机描述的。这样一个实际的最大值在涉及动态表面的HS-AFM实验设置中可能会很有用，从而有助于选择观察尺寸、图像像素化和采样率之间最简约的关系。为了协助进行上述计算，一个名为HS-AFM UGOKU的基于图形用户界面的软件包可免费获取。
