Institute for Personalized Medicine, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China.
Nanoscale. 2018 Mar 15;10(11):5133-5139. doi: 10.1039/c7nr09483c.
Cellular membranes are important biomaterials with highly dynamic structures. Membrane dynamics plays an important role in numerous cellular processes, but precise tracking it is challenging due to the lack of tools with a highly sensitive and fast detection capability. Here we demonstrate a broad bandwidth optical imaging technique to measure cellular membrane displacements in the normal direction at sub-nm level detection limits and 20 μs temporal resolution (1 Hz-50 kHz). This capability allows us to study the intrinsic cellular membrane dynamics over a broad temporal and spatial spectrum. We measured the nanometer-scale stochastic fluctuations of the plasma membrane of HEK-293 cells, and found them to be highly dependent on the cytoskeletal structure of the cells. By analyzing the fluctuations, we further determine the mechanical properties of the cellular membranes. We anticipate that the method will contribute to the understanding of the basic cellular processes, and applications, such as mechanical phenotyping of cells at the single-cell level.
细胞膜是具有高度动态结构的重要生物材料。膜动力学在许多细胞过程中起着重要作用，但由于缺乏具有高度灵敏和快速检测能力的工具，因此精确跟踪它具有挑战性。在这里，我们展示了一种宽带光学成像技术，可在亚纳米级检测极限和 20 μs 时间分辨率（1 Hz-50 kHz）下测量细胞膜在法向方向上的位移。这种能力使我们能够在广泛的时间和空间范围内研究细胞膜的固有动力学。我们测量了 HEK-293 细胞质膜的纳米级随机波动，发现它们高度依赖于细胞的细胞骨架结构。通过分析波动，我们进一步确定了细胞膜的力学性质。我们预计该方法将有助于理解基本的细胞过程，并在单细胞水平上对细胞的机械表型进行应用。
