Development of micropost force sensor array with culture experiments for determination of cell traction forces.

Cell traction forces (CTFs) are critical for cell motility and cell shape maintenance. As such, they play a fundamental role in many biological processes such as angiogenesis, embryogenesis, inflammation, and wound healing. To determine CTFs at the sub-cellular level with high sensitivity, we have developed high density micropost force sensor array (MFSA), which consists of an array of vertically standing poly(dimethylsiloxane) (PDMS) microposts, 2 microm in diameter and 6 microm in height, with a center-to-center distance of 4 microm. In combination with new image analysis algorithms, the MFSA can achieve a spatial resolution of 40 nm and a force sensitivity of 0.5 nN. Culture experiments with various types of cells showed that this MFSA technology can effectively determine CTFs of cells with different sizes and traction force magnitudes.