Stress relaxation of HepG2 cells measured by atomic force microscopy
Stress relaxation of HepG2 cells measured by atomic force microscopy
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DOI：
10.1088/0957-4484/18/8/084010
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发表时间：
2007-01
期刊：
影响因子：
3.5
通讯作者：
T. Okajima;M. Tanaka;S. Tsukiyama;T. Kadowaki;S. Yamamoto;M. Shimomura;H. Tokumoto
中科院分区：
文献类型：
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作者：
T. Okajima;M. Tanaka;S. Tsukiyama;T. Kadowaki;S. Yamamoto;M. Shimomura;H. Tokumoto
用原子力显微镜 (AFM) 检查 HepG2 细胞的应力松弛。在测量中，通过AFM尖端向单元施加负载力，并在悬臂基座位移的固定位置处测量悬臂偏转信号的时间序列。在 HepG2 细胞上可以清楚地观察到加载力的松弛，并且非常适合称为 Kohlrausch-Williams-Watts (KWW) 函数的拉伸指数函数，该函数根据经验用于表示系统的分散过程。松弛时间和拉伸指数参数估计分别为~0.5 s和0.4-0.6。后者表明在 HepG2 细胞中观察到的弛豫由多个弛豫过程组成。此外，发现松弛过程的特征与细胞的弹性特性没有很强的相关性。
Stress relaxation of HepG2 cells was examined with an atomic force microscope (AFM). In the measurement, a loading force was applied to the cell by an AFM tip, and a time series of the cantilever deflection signal was measured at a fixed position of the cantilever base displacement. The relaxation of the loading force was clearly observed on the HepG2 cells, and was well fitted to a stretched exponential function known as the Kohlrausch–Williams–Watts (KWW) function, which is empirically employed to represent dispersion processes of the system. The relaxation time and the stretching exponent parameter were estimated to be ∼0.5 s and 0.4–0.6, respectively. The latter indicated that the relaxation observed in HepG2 cells consisted of multiple relaxation processes. Moreover, it was found that the characteristic feature of the relaxation process was not strongly correlated with the elastic properties of the cells.