Cross-Link of Telechelic Diacrylate Polyethylene-Glycol in Peptide-Based Fmoc-FF Hydrogel Matrices

Hydrogels (HGs) with enhanced structural and mechanical properties can be generated by combining two or more different building blocks in the same matrix. It has been widely demonstrated that the addition of peptides, proteins, sugars, or polymers to the low molecular weight hydrogelator Fmoc-FF [(fluorenyl methyloxycarbonyl)-diphenylalanine] can significantly modify the chemical and structural features of the resulting HGs. In this context, the formulation of multicomponent HGs has been previously described, in which Fmoc-FF is mixed with telechelic diacrylate α-/ω-substituted polyethylene-glycol derivatives (PEGDAs) with a molecular weight of 575 (PEGDA1) or 250 Da (PEGDA2). Here, we investigate the possibility to generate Fmoc-FF-based interpenetrated networks performing the cross-link reaction of PEGDA monomers in supramolecular peptide hydrogels. This approach can allow the modulation of the final properties of the material, in terms of water behavior, topography, and rigidity. The results indicate that the polymerization time, the polymer length, and the Fmoc-FF/PEGDA ratio play a crucial role in the chemistry of the materials and, consequently, of their potential application.