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Mussel proteins have long been known to produce components that are both strong and flexible, something that artificial materials have long struggled to combine. Mussel foot protein 1 (mfp-1) is found to be present in varying concentrations in the byssal threads of Mytilus Californianus, forming a cuticle about the soft core composed of harder granules surrounded by a more flexible matrix. The granules appear to contain a higher concentration of mfp-1 to the surrounding matrix, raising the question whether the concentration of mfp-1 present changes its adhesive properties and therefore the properties of the components it makes up. The adhesive properties were investigated using a Surface Forces Apparatus (SFA) which records the forces generated when two surfaces are put in contact and then separated, making it ideal for the study of adhesion. Three concentrations of mfp-1 were tested: 10, 50 & 100 μg/ml in solution. Either one surface was treated with protein (adhesion between proteins and surface) or both (cohesion between opposite proteins); the surfaces were then left in contact for varying lengths of time before separation. The results suggest there is an optimal concentration (around 50 μg/ml) forming the strongest bonding which plateaus to a constant force with increasing concentration. The adhesive forces are stronger than the cohesive, and contact time also plays a role in the extent of adhesion. It is safe to assume there is promising research to be done in finding this optimal concentration and the bonding mechanisms that cause these characteristics.