Fast Fluorescence Microrheology

Investigators: Maxine Jonas, Peter So

nic.med.harvard.edu

To gain insight in this field, we choose to monitor the frequency-dependent complex shear modulus G*(w) by a nondestructive method that does not incorporate any foreign body into the cell. This method of laser tracking extracts information from the Brownian motion of individual spherical particles embedded in the viscoelastic cytoskeletal mesh.

We use a differential detection system in a novel laser device to ascertain the trajectory of the particle with sub-nanometer and near-microsecond resolution, information that can be related to G*(w). This technique provides a way to quantify the viscoelastic behavior of the cell with wide bandwidth (five decades of frequencies).

Additionally, incorporating fluorescence in this assay will allow us to discriminate organelles or cellular locations of interest in cardiovascular cells (see figure above).