Cross-linking and multilayer adsorption of mussel adhesive proteins

The adhesive power of the mussel is the reason that mussel adhesive proteins have been studied as a (model) system for a possible medical adhesive. After oxidation, the Dopa groups of the blue mussel (Mytilus edulis) foot protein Mefp-1 form Dopa-Dopa-quinone cross-links, which leads to the formation of aggregates. By assuming multilayer adsorption, in which the adsorbed aggregates have to deform before the second layer can adsorb on top of them, we are able to describe the adsorption kinetics of the Mefp-1 aggregates. The rate of conformational change after adsorption and the sticking probability for the formation of the second layer increase with increasing Mefp-1 bulk concentrations. We conclude that the rate of aggregation in solution has a significant effect on the compliance of the formed aggregates as well as on the structure of the adsorbed layers. The formation of an adsorbed layer from highly cross-linked aggregates is expected to affect the performance as an adhesive layer.