The number distribution of complex shear modulus of single cells measured by atomic force microscopy.
The viscoelastic properties of a large number of mouse fibroblast NIH3T3 cells (n approximately 130) were investigated by combining atomic force microscopy (AFM) with a microarray technique. In the experiments, the cells were arranged and cultured in the wells of a microarray substrate, and a force modulation mode experiment was used to measure the complex shear modulus, G*, of individual cells in a frequency range 0.5-200Hz. The frequency dependence of G* of the cells exhibited a power-law behavior and similar frequency dependencies have been observed in several cell types cultured on flat substrates. This indicated that the NIH3T3 cells cultured in the wells of a microarray have analogous structural organization to those cells cultured on flat substrates. The number distribution of both the storage and loss moduli of G* fitted well to a log-normal distribution function, whereas the power-law exponent estimated by a power-law structural damping model showed a normal distribution function. These results showed that combining AFM with a microarray technique was a suitable approach for investigating the statistics of rheological properties of living cells without the requirement of cell surface modification.
Graduate School of Information Science and Technology, Hokkaido University, Kita-ku N14 W9, Sapporo 060-0814, Japan.
Shinichiro
S
Hiratsuka
Yusuke
Y
Mizutani
Masahiro
M
Tsuchiya
Koichi
K
Kawahara
Hiroshi
H
Tokumoto
Takaharu
T
Okajima
D016475:3T3 Cells; D000818:Animals; D002448:Cell Adhesion; D004548:Elasticity; D005347:Fibroblasts / Q000502:physiology*; D051379:Mice; D018625:Microscopy, Atomic Force / Q000379:methods*; D013314:Stress, Mechanical