title: Metal-Ligand Interactions and Salt Bridges as Sacrificial Bonds in Mussel Byssus-Derived Materials.
abstract: The byssus that anchors mussels to solid surfaces is a protein-based material combining strength and toughness as well as a self-healing ability. These exceptional mechanical properties are explained in part by the presence of metal ions forming sacrificial bonds with amino acids. In this study, we show that the properties of hydrogel films prepared from a byssus protein hydrolyzate (BPH) can also be improved following the biomimetic formation of sacrificial bonds. Strengthening and toughening of the materials are both observed when treating films with multivalent ions (Ca2+or Fe3+) or at the BPH isoelectric point (pI) as a result of the formation of metal-ligand bonds and salt bridges, respectively. These treatments also provide a self-healing behavior to the films during recovery time following a deformation. While pI and Ca2+treatments have a similar but limited pH-dependent effect, the modulus, strength, and toughness of the films increase largely with Fe3+concentration and reach much higher values. The affinity of Fe3+with multiple amino acid ligands, as shown by vibrational spectroscopy, and the more covalent nature of this interaction can explain these observations. Thus, a judicious choice of treatments on polyampholyte protein-based materials enables control of their mechanical performance and self-healing behavior through the strategic exploitation of reversible sacrificial bonds.
authors: Département de Chimie, Université de Montréal , Montréal, Québec H3C 3J7, Canada.|Département de Chimie, Université du Québec à Montréal , Montréal, Québec H3C 3P8, Canada.
authors: Frédéric
authors: F
authors: Byette
authors: Département de Chimie, Université de Montréal , Montréal, Québec H3C 3J7, Canada.
authors: Audrey
authors: A
authors: Laventure
authors: Département de Chimie, Université du Québec à Montréal , Montréal, Québec H3C 3P8, Canada.
authors: Isabelle
authors: I
authors: Marcotte
authors: Département de Chimie, Université de Montréal , Montréal, Québec H3C 3J7, Canada.
authors: Christian
authors: C
authors: Pellerin
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D000818:Animals; D032701:Biomimetics; D049872:Bivalvia / Q000737:chemistry; D007477:Ions / Q000737:chemistry; D008024:Ligands; D055595:Mechanical Phenomena; D008670:Metals / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D007477:Ions; D008024:Ligands; D008670:Metals; D011506:Proteins; D012965:Sodium Chloride