Micromachined force sensors for the study of cell mechanics

A technique using micromachined mechanical force sensors to measure the force response of living cells is introduced. The force sensors consist of a probe and flexible beams. The probe is used to indent and stretch the cells, and the flexible beams are used to measure the cell force response. The stiffness of the sensors is designed at several nanonewtons per micrometer, but can be varied over a wide range. The sensors are fabricated by the SCREAM process. The deformation of the cells and the deflection of flexible beams are measured by an optical microscope coupled with a charge-coupled device camera. Experimental demonstrations show the feasibility, simplicity, and versatility of this technique. It addresses several disadvantages of existing related techniques, and is complementary to many of them. We expect that this new technique will attract significant attention and be employed much more in the study of cell mechanics.