Studies on the physicochemical properties, gelling behavior and drug release performance of agar/κ-carrageenan mixed hydrogels

• Published in: International journal of biological macromolecules 2020-07, Vol.154, p.878-887
• Main Authors: Zhao, Jingkun, Sun, Ce, Li, Haiyan, Dong, Xu, Zhang, Xiaodong
• Format: Article
• Language: English
• Subjects: Agar - chemistry; Agar/κ-carrageenan mixed hydrogels; Carrageenan - chemistry; Drug Carriers - chemistry; Drug Liberation; Drug release; Hydrogels - chemistry; Intermolecular interactions; Metformin - administration & dosage; Viscosity
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2020.03.087

A series of agar/κ-carrageenan mixed hydrogels with different mass ratios were prepared, and their physicochemical properties, gelling behavior and drug release performance were determined and analyzed. The results showed that the gel strength, the gelling temperature and the gel melting temperature decreased with the increase of κ-carrageenan, while the apparent viscosities increased. Optical rotation and differential scanning calorimetry (DSC) indicated that there did exist intermolecular interactions between agar and κ-carrageenan, and the detailed gelling mechanism of the mixed hydrogels was proposed, which was different from that of the previous research. Besides, agar/κ-carrageenan mixed hydrogels were used as carriers for the delivery of metformin hydrochloride (MET). The results showed that the drug loading efficiency and the sustained release capacity of agar hydrogels could be enhanced by the addition of κ-carrageenan, and the release profile was mainly dominated by the electrostatic interaction between the MET and the polysaccharides. These results indicated that κ-carrageenan had the potential to improve the physicochemical properties and drug release performance of agar hydrogel. •Optical rotation and DSC results indicated the formation of mixed double helixes.•The physicochemical properties of the mixed hydrogels were significantly changed.•Texture and FT-IR results proved the interactions between the two molecules.•Cryo-SEM showed that the mixed hydrogel had denser network structure.•The mixed hydrogel showed a sustained release of MET.