Probing local lateral forces of focal adhesions and cell-cell junctions of living cells by torsional force spectroscopy.

The number and strength of mechanical connections of cells to their local environment can be indicative of their migration and invasion potential. Gaining direct access to the mechanical properties of individual connections and bringing them into a relationship with the state of disease, however, is a formidable task. Here, we present a method to directly sense focal adhesions and cell-cell contacts with a force sensor to quantify the lateral forces of their anchoring points.

Torsional and lateral eigenmode oscillations for atomic resolution imaging of HOPG in air under ambient conditions.

Combined in-plane and out-of-plane multifrequency atomic force microscopy techniques have been demonstrated to be important tools to decipher spatial differences of sample surfaces at the atomic scale. The analysis of physical properties perpendicular to the sample surface is routinely achieved from flexural cantilever oscillations, whereas the interpretation of in-plane sample properties via force microscopy is still challenging. Besides the torsional oscillation, there is the additional option to exploit the lateral oscillation of the cantilever for in-plane surface analysis.