Figure 7.

Schematic of the proposed wear protection mechanism. Coacervates, condensed by numerous transient electrostatic interactions between lysine and carboxylate moieties (purple asterisk), (a) isotropically distribute in the bulk solution and (b) distribute asymmetrically under compressive shear with mfp-1 (yellow) preferentiality bound to the surface. Adding Dopa to mfp-1 increases adhesion to mica (red asterisk) and increases wear protection by shifting the slip-plane away from the mica and into the intervening layer enriched with HA (green).