Development of a Polyaspartic Acid Hydrogel Fabricated Using Pickering High Internal Phase Emulsions as Templates for Controlled Release of Drugs

A series of monolithic open-pore structure hydrogels based on polyaspartic acid (PASP) grafted onto polyacrylic acid (PAA) were prepared using a Pickering high internal phase emulsion (HIPEs). The influence of the internal phase volume, concentrations of surfactant and particle stabilizer on the void inter-connectivity and average pore diameter of the hydrogels were studied. Furthermore, controlled release properties of PASP-g-PAA hydrogels were evaluated. It was assessed that prepared hydrogels have an excellent open-interconnected framework structure with excellent adsorptive property. In addition, the release behaviors of drugs loaded into hydrogels were controlled by external stimuli. The correlative release profiles of salicylic acid were 30.8 wt% at pH 1.2 (simulated gastric fluid) and 61.9 wt% at pH 7.4 (simulated intestinal fluid) at 37 degrees C. These results indicate that synthesized PASP-g-PAA hydrogels have significant potential applications in drug delivery.