Cell Manipulation System Based on a Self-Calibrating Silicon Micro Force Sensor Providing Capillary Status Monitoring

In this paper, a system for cell manipulation is presented. A two axis stage is arranged on an inverted microscope to place cells in focus. Cell manipulation can thereby be observed while the system automatically runs force controlled measurements. A high precision linear motor moves a force sensor, which has been equipped with a stimulation tool, e.g., a micro capillary for cell injection. The sensor is made up of silicon and consists of a membrane with a boss structure, which enables measurements as low as 120μ N. For the first tests, an injection capillary is mounted on the topside, while the backside is fixed to a printed circuit board with an integrated air pressure connection. Air pressure was applied under the membrane because the glass capillaries with outer diameters of at least 1μ mdo not allow calibration via other force sensors. This setup provides a self-calibration of the mounted sensor system, before the measurements of the occurred forces on the cells during the penetration of the capillary. Using the 3-D force measurement capability of the sensor, the system features a unique end-effector status monitoring.