The number distribution of complex shear modulus of single cells measured by atomic force microscopy

Ultramicroscopy. 2009 Jul;109(8):937-41. doi: 10.1016/j.ultramic.2009.03.008. Epub 2009 Mar 19.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3 Cells
  • Animals
  • Cell Adhesion
  • Elasticity*
  • Fibroblasts / physiology*
  • Mice
  • Microscopy, Atomic Force / methods*
  • Stress, Mechanical