Figure 4.

High-resolution elastic modulus mapping of cells. AFM height images were overlaid with elastic modulus maps to determine localized mechanical properties for single cells and cell-cell interfaces. These 128×128 pt. scans were collected within six minutes using a scan rate of 2 Hz and demonstrate the possible applications of the force scanning technique. The single ASC exhibited lower moduli (0.5–1 kPa) over the nucleus and perinuclear region and higher moduli near its edges (3–10 kPa) (a–c). The interface between two NIH3T3 fibroblasts is difficult to discern using either phase contrast microscopy (d) or AFM height images (e). However, by mapping mechanical properties to the height image, a clearer distinction between the cells can be detected (f). In this case, the filopodia of adjacent cells exhibited variable elastic moduli depending on their immediate, underlying material (i.e. glass, 6–10 kPa or cell, 3–4 kPa).