Experimental and numerical studies on the viscoelastic behavior of living cells

Abstract

This thesis focused on the viscoelastic behavior of living cells. One objective was to test the power-law rheology hypothesis for suspended NIH 3T3 fibroblasts using micropipette aspiration. The other was to build a finite element model of cells based on the power-law rheology and to simulate the micropipette aspiration experiments. Through experiments, it was found that larger pipettes are more suitable for probing cell rheology than smaller ones in terms of consistency and reproducibility. The power-law rheology model was found to accurately fit the creep functions of suspended fibroblasts, providing new support to this model for suspended cells. The finite element model based on the power-law rheology could predict the experimental observations quantitatively. It is hoped that the experimental methodology and theoretical model proposed in this thesis will contribute to better understanding of the biological response of cells to mechanical stimuli.