EAK hydrogels cross-linked by disulfide bonds: Cys number and position are matched to performances

Hydrogels produced by self-assembling peptides are intrinsically biocompatible and thus appropriate for many biomedical purposes. Their application field may be even made wider by reducing the softness and improving the hydrogel mechanical properties through cross-linking treatments. To this aim, modifications of EAK16-II sequence by including Cys residues in its sequence were here investigated in order to obtain hydrogels cross-linkable through disulfide bridge. Two sequences, namely C-EAK and C-EAK-C that contain Cys residues at the N-terminus or at both ends were characterized. Fiber forming abilities, biological and dynamic mechanical properties were explored before and after the oxidative treatment. In particular, the oxidized version of C-EAK presents a good cell viability and sustains osteoblast proliferation. Furthermore, molecular dynamics simulations on monomeric and assembled forms of the peptides were performed. Molecular dynamics simulations explained how a specific Cys functionalization was ...