Dresden 2020 – wissenschaftliches Programm

Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 13: Cell Mechanics I

BP 13.6: Vortrag

Dienstag, 17. März 2020, 11:30–11:45, SCH A251

Measuring Viscoelasticity of Cells by Atomic Force Microscopy — Sandra Perez Dominguez, Shruti Kulkarnie, Carmela Rianna, Prem Kumar Viji Babu, and •Manfred Radmacher — Universität Bremen

Mechanical properties of cells are important for understanding many cellular processes like cell division, cell migration or wound healing. From a mechanical point of view, the most important component of a (mammalian) cell is the actin cytoskeleton, which is an active polymeric network able to generate internal stresses and external forces. If a local deformation is applied to a cell, e.g. by an AFM tip, the response will be viscoelastic, where the elastic forces are mainly generated by the cytoskeleton, and the viscous forces may stem from the interaction of the cytoskeleton with the highly viscous cytoplasm. There are various experimental methods to determine this viscoelastic response by AFM: the simplest are applying a jump in force or a modulating force. The former measures the creep of the sample, the latter is conceptually related to polymer rheology. We will discuss and compare both methods in AFM to determine the viscoelastic response of different cell types.

We have investigated several cell types, including cancer and normal cells, but also various types of fibroblasts, which are related to wound healing or Dupuytren's disease. In all cases we could quantify differences in the mechanical properties: in the elastic and the loss modulus, and in the power law exponents of these quantities as a function of frequency.