Dependence of aggrecan self-adhesion on surface dwell time and bath IS. (a) Maximum adhesion forces, Fad (open symbols), and (b) total adhesion energy, Ead (closed symbols), as a function of surface dwell time, t, between an OH-SAM- and an aggrecan-functionalized planar substrate; (c) Fad (open symbols) and (d) Ead (closed symbols) as a function of surface dwell time, t, between two opposing aggrecan end-grafted layers (c and d) in 0.001–1.0 M NaCl, pH ∼5.6 (Fmax ≈ 45 nN, z ≈ 4 μm/s; mean ± SE, n ≥ 30 for each surface dwell time, t, at each IS). Statistically significant differences were observed for Fad and Ead at different surface dwell times, t, and different IS values measured by both OH-SAM and aggrecan probe tips (two-way ANOVA, pt < 0.0001, pIS < 0.0001).