Mechano- and Visco-NPS: An Electronic Method to Measure the Mechanical Properties of Cells: Nano Seminar Series

Seminar | March 1 | 2-3 p.m. | 4 LeConte Hall

 Prof. Lydia Sohn, UC Berkeley, Mechanical Engineering

 Berkeley Nanosciences and Nanoengineering Institute

We have developed an efficient, label-free method of screening cells for their phenotypic profile, which we call Node-Pore Sensing (NPS). NPS involves measuring the modulated current pulse caused by a cell transiting a microfluidic channel that has been segmented by a series of inserted nodes.

Previously, we showed that when segments between the nodes are functionalized with different antibodies corresponding to distinct cell-surface antigens, immunophenotyping can be achieved.

In this talk, I will show how we have significantly advanced NPS by simply inserting between two nodes a “contraction” channel through which cells can squeeze. “Mechano-NPS”, as we now call our method, can simultaneously measure a cell’s size, resistance to deformation, transverse deformation, and ability to recover from deformation. As I will show, mechano-NPS can distinguish malignant from non-malignant epithelial cells and discriminate between sub-lineages and, excitingly, chronological age groups of primary human mammary epithelial cells. By replacing the contraction channel with one that is sinusoidal in shape, we can measure the viscoelastic properties (elasticity and viscosity) of cells. I will show how “visco-NPS” can quantify the mechanical transitions of cells as they traverse the cell cycle or are initiated into an epithelial-mesenchymal transition.

Lydia Sohn did her PhD in Physics at Harvard and postdoc at Bell Labs, then spent a decade on the Princeton Physics faculty before joining UCB Mechanical Engineering in 2003. Awards include the NSF CAREER and several biomedical prizes. She also serves in the joint bioengeneering program with UCSF.