All the designed scaffolds are based on the tetrapeptide sequence Arg-Ala-Asp-Ala repeated four times, a glycine linker, Ala-Ala-Pro-Val, another glycine linker and a functional motif, which are presented in a general scheme in Figure . The linkers were added for better access for the enzyme to the cleavage site, as the RADA16-I structure is tightly arranged -a factor which is crucial for its gelation. The designed peptides are listed in Table .