A novel hydrogelator based on dimeric-dehydrocholic acid derivative

A dimeric-dehydrocholic acid derivative (DDAD) was synthesized and studied for its gelation ability in the potassium hydroxide solution. The DDAD-based gels were further investigated for their thermal stabilities and morphological structures by using the vial inversion method, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Interestingly, the TEM and AFM images of the DDAD-based gels indicated that the supramolecular structures were composed of longer fibers. Importantly, Fourier transformation infrared spectra further revealed that the main driving forces in gel formation involve multiple hydrogen bonding, electrostatic, and dipole-dipole interactions among the gelator molecules. The X-ray diffraction analysis showed that the molecular packings in both the DDAD powders and the organogel phase were highly disordered. Based on these results, a mechanism for the formation of hydrogels is proposed. These findings present a novel hydrogelator and an insight into developing new types of gels as potential soft materials.