“…The sharp tip is attached to a soft cantilever, and, as the cantilever bends, its deflection is detected by movement of a laser beam reflected from the tip. AFM topographic imaging is widely used in the life sciences, and has provided high-resolution images of biomolecules, membranes and cells in buffer at unprecedented resolution (Dufrêne, 2008a, Dufrêne, 2008bEngel and Gaub, 2008;Müller and Dufrêne, 2011;Müller et al, 2009 (Hinterdorfer and Dufrêne, 2006;Engel and Gaub, 2008;Puchner and Gaub, 2009;Müller et al, 2009;Dufrêne et al, 2011). Here, the tip is brought into proximity of and retracted from the biological sample, and the cantilever deflection measures the interaction force (Fig.…”