A general approach for the microrheology of cancer cells by atomic force microscopy

Biran Wang (1) , Pascal Lançon (1) , Céline Bienvenu (2) , Pierre Vierlingb (2) , Christophe Di Giorgio (2) , Georges Bossis (1)

1 LPMC - Laboratoire de physique de la matière condensée
2 LCMBA - Laboratoire de Chimie des Molécules Bioactives et des Arômes

The determination of the viscoelastic properties of cells by atomic force microscopy (AFM) is mainly realized by looking at the relaxation of the force when a constant position of the AFM head is maintained or at the evolution of the indentation when a constant force is maintained. In both cases the analysis rests on the hypothesis that the motion of the probe before the relaxation step is realized in a time which is much smaller than the characteristic relaxation time of the material. In this paper we carry out a more general analysis of the probe motion which contains both the indentation and relaxation steps, allowing a better determination of the rheological parameters. This analysis contains a correction of the Hertz model for large indentation and also the correction due to the finite thickness of the biological material; it can be applied to determine the parameters representing any kind of linear viscoelastic model. This approach is then used to model the rheological behavior of one kind of cancer cell called Hep-G2. For this kind of cell, a power law model does not well describe the low and high frequency modulus contrary to a generalized Maxwell model.

Mots clés: Microrheology; Cancer cell; Atomic force microscopy; Biomechanics and viscoelasticity

Domaines: Matériaux; Science des matériaux [cond-mat.mtrl-sci]; Biophysique [physics.bio-ph]; Interactions cellulaires [q-bio.CB]

Biran Wang, Pascal Lançon, Céline Bienvenu, Pierre Vierlingb, Christophe Di Giorgio, et al.. A general approach for the microrheology of cancer cells by atomic force microscopy. Micron, 2013, 44, pp.287-297. ⟨10.1016/j.micron.2012.07.006⟩. ⟨hal-00759704⟩