Simple Guanosine-Amino Acid Hybrids as Low Molecular Weight Hydrogelators

While amino acids and nucleosides are the building blocks of molecular biology, very little is known about the behavior of simple hybrids consisting of a combination of these units. Here, we report the synthesis and self-assembly of derivatives obtained by covalently linking guanosine (G) and amino acids (Gly and Ala). When triggered by a base, these hybrids behave as single-component, low-molecular-weight hydrogelators through K⁺-mediated formation of G-quadruplexes, which are the supramolecular structural units responsible for physical gelation. The hydrogels were characterized by rheological measurements, circular dichroism (CD), and scanning electron microscopy (SEM). These transparent gels exhibit remarkable long-term stability (months). Despite minimal differences in molecular structure, the conjugates form hydrogels with markedly distinct rheological and spectroscopic properties, enabling fine modulation of gel behavior. Overall, this work introduces a new class of guanosine-based amino acid hydrogelators with potential applications spanning biomedicine and catalysis.