Determination of viscoelastic cell properties from stress relaxation experiments with AFM

The fourth article on the use of atomic force microscopy to study the mechanical properties of biological materials is out.

  • Experimental set-up, force-time curve
    vergrößern
    a) Experimental set-up with cantilever, laser spot, and cell sample. b) Representation of the force–time curve

In this work we show, taking the advantage of the viscoelastic properties of HeLa cells, how to perform stress relaxation experiments. In particular, we have exposed the cells to several external forces (1, 2, 4, and 8 nN) during different pause times (1, 10, and 60 s). The manuscript discuss which linear viscoelastic models can be used to fit the experimental data, being the best five element Maxwell model. This primer in microscopy serves as an introduction and guide when performing stress relaxation experiments on soft materials using AFM. The work is part of the long-term collaboration of the members of the Institute of Biophysics with Rafael Benitez (Faculty of Economy of the University of Valencia).

 

Authors: Andreas Weber, Rafael Benitez, José Luis Toca-Herrera

Microscopy Research and Technique, 85, October 2022, https://doi.org/10.1002/jemt.24184

 

11.11.2022