Study on the properties of agar/gellan gum/ι-carrageenan ternary mixed hydrogel drug loading system and its sustained release performance

Natural edible polysaccharides are excellent materials for preparing drug release systems. In this study, the new type agar/gellan gum/ι-carrageenan ternary mixed hydrogel drug loading systems were prepared and their properties and slow-release performance were studied. Optical rotation, scanning electron microscopy (SEM) and rheological property analyses confirmed that the molecules of agar (AG), gellan gum (GG) and ι-carrageenan (CA) could interact to form double helix structures, and the three kinds of molecules together constructed the three-dimensional network structure in process of forming hydrogel. The ternary mixed hydrogel drug loading systems exhibited excellent metformin hydrochloride (MET) slow-release performance, the cumulative MET release rate of the optimum hydrogel system in simulated gastric juice (2 h) was 46.12%, and the total cumulative MET release rate in simulated gastric juice and intestinal juice (10 h) could reach up to 91.24%. The drug release kinetics analysis indicated that the slow-release mechanism of the prepared hydrogel was consistent with Fick’s diffusion mechanism. Texture evaluation showed that the texture of the prepared hydrogel was similar to that of commercial Liangfen and fruit jelly. The results exhibited a new idea for the development of safe and efficient hydrogel-type drug sustained release systems.