Assembly Properties of an Alanine-Rich, Lysine-Containing Peptide and the Formation of Peptide/Polymer Hybrid Hydrogels

An alanine-based peptide doped with charged lysines with a sequence of (AKA(3)KA)(2) (AK2) was selected from the crosslinking regions of the natural elastin as a starting point for the fabrication of chemically diverse and structurally complex peptide/polymer hybrid hydrogels. At low peptide concentration, Pluronic F127 (F127) micelles are capable of increasing the peptide helicity and stabilizing it against thermal denaturation. At higher peptide concentration in basic media, the AK2 peptide developed a substantial amount of beta-sheet structure. The self-assembled nanoscale structures were covalently interlocked. The crosslinked hybrid hydrogels were viscoelastic, exhibiting an elastic modulus of approximately 17 kPa and a loss tangent of 0.2.