Power-law rheology analysis of cells undergoing micropipette aspiration
- 456 Downloads
Accurate quantification of the mechanical properties of living cells requires the combined use of experimental techniques and theoretical models. In this paper, we investigate the viscoelastic response of suspended NIH 3T3 fibroblasts undergoing micropipette aspiration using power-law rheology model. As an important first step, we examine the pipette size effect on cell deformation and find that pipettes larger than ~7 μm are more suitable for bulk rheological measurements than smaller ones and the cell can be treated as effectively continuum. When the large pipettes are used to apply a constant pressure to a cell, the creep deformation is better fitted with the power-law rheology model than with the liquid drop or spring-dashpot models; magnetic twisting cytometry measurement on the rounded cell confirms the power-law behavior. This finding is further extended to suspended cells treated with drugs targeting their cytoskeleton. As such, our results suggest that the application of relatively large pipettes can provide more effective assessment of the bulk material properties as well as support application of power-law rheology to cells in suspension.
KeywordsCell mechanics Cytoskeleton Deformability Soft glassy rheology Viscoelasticity Optical magnetic twisting cytometry
Unable to display preview. Download preview PDF.
- Danowski BA (1989) Fibroblast contractility and actin organization are stimulated by microtubule inhibitors. J Cell Sci 93(Pt 2): 255–266Google Scholar
- Fabry B, Maksym GN, Shore SA, Moore PE, Panettieri RA Jr, Butler JP, Fredberg JJ (2001b) Selected contribution: time course and heterogeneity of contractile responses in cultured human airway smooth muscle cells. J Appl Physiol 91(2): 986–994Google Scholar
- Fabry B, Maksym GN, Butler JP, Glogauer M, Navajas D, Taback NA, Millet EJ, Fredberg JJ (2003) Time scale and other invariants of integrative mechanical behavior in living cells. Phys Rev E Stat Nonlin Soft Matter Phys 68(4 Pt 1): 041914Google Scholar
- Flugge W (1967) Viscoelasticity. Blaisdell Publishing Company, WalthamGoogle Scholar
- Guck J, Schinkinger S, Lincoln B, Wottawah F, Ebert S, Romeyke M, Lenz D, Erickson HM, Ananthakrishnan R, Mitchell D, Kas J, Ulvick S, Bilby C (2005) Optical deformability as an inherent cell marker for testing malignant transformation and metastatic competence. Biophys J 88(5): 3689–3698CrossRefGoogle Scholar
- Mijailovich SM, Kojic M, Zivkovic M, Fabry B, Fredberg JJ (2002) A finite element model of cell deformation during magnetic bead twisting. J Appl Physiol 93(4): 1429–1436Google Scholar
- Nash GB, Obrien E, Gordonsmith EC, Dormandy JA (1989) Abnormalities in the mechanical-properties of red blood-cells caused by plasmodium-falciparum. Blood 74(2): 855–861Google Scholar
- Price LS, Leng J, Schwartz MA, Bokoch GM (1998) Activation of Rac and Cdc42 by integrins mediates cell spreading. Mol Biol Cell 9(7): 1863–1871Google Scholar
- Wang N, Tolic-Norrelykke IM, Chen J, Mijailovich SM, Butler JP, Fredberg JJ, Stamenovic D (2002) Cell prestress. I. Stiffness and prestress are closely associated in adherent contractile cells. Am J Physiol Cell Physiol 282(3): C606–C616Google Scholar
- Zhou EH (2006) PhD thesis: experimental and numerical studies on the viscoelastic behavior of living cells. Department of Civil Engineering. National University of Singapore, SingaporeGoogle Scholar
- Zhou EH, Quek ST, Lim CT (2010) Finite element simulation of micropipette aspiration based on power-law rheology (in preparation)Google Scholar