(464h) Formation of Supramolecular Hydrogel Microspheres Via Microfluidics

Supramolecular hydrogels have attracted increasing interest in recent years due to their fascinating physical and morphological properties and their potential applications in drug delivery, oil recovery, and tissue engineering. Supramolecular hydrogel microspheres are hydrogel particles formed by the self-assembly of hydrogelators in water, through noncovalent interactions. In comparison with the traditional bulk format of the supramolecular hydrogels, hydrogel microspheres provide faster responses to external stimuli. In this paper, we provide a novel strategy to prepare supramolecular hydrogel microspheres with diameters ranging from 15 to 105 microns by using microfluidics. Optical and scanning electron microscopy (SEM) demonstrate that compact entanglement round cage-like aggregates of hydrogelator were formed within the supramolecular hydrogel microsphere, in contrast to loose and less compact aggregates within bulk hydrogel. Thermal analysis (DSC) indicates that supramolecular hydrogel microspheres are more thermally stable and can immobilize more water molecules, owing to compact entangled three-dimensional network structures. This observation is of particular importance for potential drug delivery, bioseparation, and biosensor applications, as it allows unstable biomolecules to be encapsulated inside the hydrogel microspheres.