Mechanical Reinforcement of Molecular Hydrogel by Co-assembly of Short Peptide-based Gelators with Different Aromatic Capping Groups

We demonstrated in this study that mixing two short peptide-based gelators with different aromatic capping groups would result in molecular hydrogels with enhanced mechanical property. We selected gelators of PTZ-GFFY and Nap-GFFY for the study. Both PTZ-GFFY and Nap-GFFY could independently form molecular hydrogel by a heating-cooling process. However, the mechanical property of gels of PTZ-GFFY and Nap-GFFY was relatively weak with storage moduli (G) of about 500 and 150 Pa, respectively. A two-component gel of PTZ-GFFY and Nap-GFFY could also form by a heating-cooling process. Surprisingly, the G value of the two-component gel was about 5000 Pa , which was at least ten times bigger than that of each single-component gel. This is a novel and simple strategy to improve the mechanical property of molecular hydrogels.