Séminaire

Vendredi 21 Février 2020 à 11h00.

Unpacking the Mechanical Correlates of Brillouin Microscopy

''Jeremie Margueritatde l'équipe Luminescence invite Darryl Overby
Abstract: Brillouin microscopy provides a non-invasive optical method to map the mechanical properties of cells and tissues at confocal resolution. The technique relies on measuring a frequency shift vB in scattered light that is proportional to the speed of acoustic waves within a material. Acoustic wave speed is related to the longitudinal elastic modulus M, which is a measure of compressibility. However, recent studies have shown that in cells, tissues and hydrogels M measured by Brillouin microscopy correlates with Young’s modulus E, which is a measure of deformability. In hydrated biological materials, M is typically many orders of magnitude larger than E. So, it is not obvious how changes in E of the order of kPa could result in changes in vB equivalent to changes in M of the order of GPa. This seminar will explore why vB and E appear to be correlated in hydrated biological materials, and to determine whether this correlation is related to water content that may affect both M and E.''