Figure 5.

Role of fibronectin (FN) in friction and wear of sheared mimLUB-coated surfaces across phosphate-buffered saline (PBS). Friction force $F_{\parallel }$ as a function of normal force $F_{\perp }$ measured across PBS between (A) mica surfaces incubated with mimLUB and (B) FN-coated mica surfaces incubated with mimLUB. The surfaces were sheared in PBS at sliding velocities of V = 0.3 µm/s (black circles), V = 3 µm/s (red triangles), and V = 30 µm/s (blue squares). Open symbols indicate measurements after the occurrence of wear in the sheared junction.