Dynamic self-shrinking peptide hydrogels with shape memory and self-healing properties

Abstract

Three peptide amphiphiles based on aromatic amino acids have been successfully synthesized, purified, and thoroughly characterized. These peptides were found to form hydrogels at physiological pH 7.46, exhibiting a unique time-dependent self-shrinking behaviour. Notably, the extent and nature of this self-shrinking varied according to the specific amino acid sequence of each peptide. In addition to this, the hydrogels demonstrated remarkable self-healing abilities and 3D shape-memory properties. To investigate the role of sequence variation, particularly the position of the L-phenylalanine residue, coarse-grained molecular dynamics simulations were employed. These simulations aimed to elucidate how different sequences influence self-assembly into the nanoscale network structures characteristic of the hydrogels. Importantly, the computational findings showed strong agreement with the experimental results, confirming the formation of distinct hydrogel architectures driven by the peptide sequences.