Knowledge-Based Tailoring of Gelatin-Based Materials by Functionalization with Tyrosine-Derived Groups

Molecular models of gelatin‐based materials formed the basis for the knowledge‐based design of a physically cross‐linked polymer system. The computational models with 25 wt.‐% water content were validated by comparison of the calculated structural properties with experimental data and were then used as predictive tools to study chain organization, cross‐link formation, and estimation of mechanical properties. The introduced tyrosine‐derived side groups, desaminotyrosine (DAT) and desaminotyrosyl tyrosine (DATT), led to the reduction of the residual helical conformation and to the formation of physical net‐points by π–π interactions and hydrogen bonds. At 25 wt.‐% water content, the simulated and experimentally determined mechanical properties were in the same order of magnitude. The degree of swelling in water decreased with increasing the number of inserted aromatic functions, while Young's modulus, elongation at break, and maximum tensile strength increased. The functionalization of gelatin with tyrosine derivatives specifically at the lysine residues leads to the reduction of Young's modulus and degree of swelling. The net‐points of the physical networks are aromatic clusters rather than triple helical regions, as shown by WAXS and molecular modeling, and therefore depend on the degree of functionalization and not the thermomechanical treatment of the materials.