Figure 1.

Strategy for measuring the BCAM/Lu-laminin binding force at the single-molecule level using AFM. (A) Schematic of the surface chemistry used to functionalize the AFM tip and substrate with LAMA5 and BCAM/Lu. A PEG-linker was attached to an AFM tip terminated with NH₂ groups, and BCAM/Lu was bound to a gold substrate via mercaptoethanesulfonate. (B) Force-distance curves are three representative examples obtained using independent tips and substrates. The uppermost (blue) curve demonstrates zero adhesive interaction, while the middle (red) and bottom (black) curves show rupture forces associated with adhesion events. (C) Dynamics of the BCAM/Lu-laminin interaction. Dependence of the adhesion force on the loading rate applied during retraction, measured between a LAMA5 tip and a BCAM/Lu substrate, while keeping the interaction time (0 s) and loading rate during approach (24000 pN/s) constant. The mean adhesion force does not notably change with the loading rate, indicating the measurements were performed close to thermodynamic equilibrium.