The crystallization process, base pair and hydrogen-bond network of guanosine derivatives-based hydrogel

摘要

In the past few decades, supramolecular gels self-assembled from low-molecular-weight gelators are attractive for various applications including regenerative medicine and drug delivery. Although guanosine-based hydrogel have a long history, a major limitation was their poor lifetime stability on account of crystallization within hours at room temperature. However, the crystallization process of guanosine-based hydrogel has not been explored before. In this work, the crystallization process of 2′-deoxy-2′-fluoroguanosine (FGd) hydrogel has been studied by single-crystal X-ray analysis and scanning electron microscope (SEM). The results indicated that the crystallization from theFGdhydrogel is divided into two phases: small flake-like and bigger piece-like crystals. Compared the flake-like with piece-like crystal, we found that they display similar torsion angle, sugar puckering, base pair and hydrogen bond patterns with subtle distinctions for the sugar-sugar and base-sugar interactions. This study not only enriches the structural varieties of guanosine derivatives, but also provides specific information to further understand how to design new guanosine-based gelators in the future.