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Marine mussels have a remarkable ability to strongly adhere to a variety of surfaces of differing chemical and physical properties under wet conditions. Mussels achieve this feat by deploying byssal threads that directly interface with surfaces through adhesive plaques containing a large number of native proteins. Recent research has indicated that the residue Dopa (3,4-dihydroxyphenylalanine) is the key chemical functionality responsible for the impressive adhesive properties of mussel plaques. Thus, there is substantial interest in implementing the adhesive properties of the Dopa group in new, synthetic wet adhesive systems. However Dopa’s susceptibility to oxidation, especially at neutral to basic pHs, is still a significant challenge for the technical translation of mussel-inspired adhesives, as the oxidized form of Dopa, Dopaquinone, exhibits poor adhesive properties. Previous studies have indicated that the local chemical environment (hydrophilicity, hydrophobicity, acidicity) surrounding Dopa residues impacts their stability towards oxidation. In this study, a model system was constructed to systematically investigate the impact of different chemical environments on Dopa stability at different pHs. We synthesized mixed alkanethiol self-assembled monolayers with terminal Dopa residues and different other chemical functionalities on molecularly-smooth gold substrates. To characterize the monolayer AFM and contact-angle studies were performed. The redox-behavior of Dopa was studied using cyclic voltammetry. Our findings will provide molecular-scale guidance for developing future bio-inspired wet adhesives for biomedical applications, such as tissue engineering.