Enhanced gelation of chitosan/β-sodium glycerophosphate thermosensitive hydrogel with sodium bicarbonate and biocompatibility evaluated

The application of chitosan/β-sodium glycerophosphate (β-GP) thermosensitive hydrogel has been limited by the relatively slow gelation, weak mechanical resistance and poor cytocompatibility. In this study, sodium hydrogen carbonate (NaHCO3) was applied with β-GP as gel agents to produce high-strength hydrogel. The hydrogels prepared with high NaHCO3 concentration or more gel agents showed shorter gelation time, better thermostability, drastically enhanced resistance in compression. Meanwhile, the hydrogels presented obvious porous structures and excellent biocompatibility to HUVEC and NIH 3T3 cultured in vitro with higher NaHCO3 concentration and moderate concentration of β-GP. Overall, appropriate concentration of β-GP combined with NaHCO3 can be a good gel regent to improve properties of chitosan thermosensitive hydrogels.