Uncovering mussel foot protein (Mfp-3)'s binding secrets: Enhanced biomimetic adhesives via mass spectrometry and residue labeling

Abstract

This study delves into the development of biomimetic adhesives, taking inspiration from the impressive underwater adhesion of mussels. In a departure from the traditional focus on DOPA, we explore a more comprehensive range of amino acids crucial for adhesion in wet environments. By utilizing amino acid labeling and mass spectrometry-based peptide mapping, we identify key peptide sequences within Mfp-3 responsible for effective aquatic adhesion. Of particular interest is the sequence YNRYARGY, which exhibits robust adhesion on both polar/acidic and hydrophobic surfaces, with an adsorption-free energy of approximately -4.5 kcal/mol (as determined by QCM). Incorporating this sequence (1% w/v), with tyrosine substitution for DOPA, into a standard PVA binder significantly enhances its adhesion capabilities. Lap-shear tests demonstrate a significant increase in PVA adhesion from 2.5 to 5 kPa on SiO2 and from 2.1 to 3.3 kPa on HDPE. These findings highlight the practical implications of our mass spectrometry approach with side chain modification in elucidating the mechanisms of mussel adhesion, thereby offering a promising strategy for advancing polymer adhesion technology.