Cell Palpation System Based on a Force Measurement by Optical Tweezers for Investigation of Local Mechanical Properties of a Cell Membrane

We have developed a cell palpation system, which enables to investigate mechanical properties of a cell in local with an optically manipulated particle. In this system, the particle attached on a cell surface is forced to move back-and-forth in sinusoidal manner by optical tweezers. Position of the particle position is recorded and analyzed to extract force exerted on the particle by using a physical model of the particle. We have demonstrated to measure cell membrane stiffness in local and temporal change of that with the detection limit of the force in pN order.