Exploring the Unexpected Gelation of Tripeptides in a Binary Mixture of Water and Ethanol

Abstract

Hydrogels formed by peptides of different length are a special class of materials that have been heavily researched in the past due to their inherent biodegradability. In this context, some low molecular weight di- or tripeptides with aromatic residues and terminal groups have been shown to form gels after self-assembling into large supramolecular structures above critical concentrations in the centimolar range. Contrary to expectations, our group recently discovered that cationic glycylanalylglycine (GAG), a tripeptide of rather limited hydrophobicity, forms a gel in 55 mol% ethanol/45 mol% water at room temperature if the concentration exceeds 200 mM.