Cell Force Sensing with Piezoresistive Micropillars

Biological cell force has been demonstrated to be an indicator of tissue health and disease. Current methods to measure cell force such as traction force microscopy or micro-pillar deflection correlate optically measured displacements to calculated forces. Although these methods have high force sensitivity, they have low throughput due to the need to analyze optical images before and after cell application.

Recent research seeks to overcome the throughput issue by the use of a sensor that can convert cell force to an electrical signal in real time as a cell exerts force. The work demonstrates a pillar deflection coupled with a silicon based piezoresistor with force resolution down to 70 nN.

This work was reported by Isha Lodhi, Durga Gajula, Devin Brown, Nikolas Roeske, David Myers, Wilbur A. Lam, Azadeh Ansari, Oliver Brand in a collaborative effort from the Georgia Tech School of Electrical & Computer Engineering, Georgia Institute of Technology, The Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, and Emory University.

The work was performed in part using an STS-Elionix ELS-G100 electron beam lithography system at the Georgia Tech Institute of Electronics and Nanotechnology (IEN).

For more information see https://lnkd.in/e-XNH5uR

peizoresistor_pillar image

Images (courtesy Isha Lodhi): (Left image) SEM image of a 300 nm by 1 micron length n-doped silicon piezoresistor. (Right Image) SEM image of a piezoresistor with a 6.7 micron diameter by 36 micron tall polymer pillar on top made with a Nanoscribe Photonic Professional GT2 system.