Effects of collagen incorporation on thermogelation and hydrogel characteristics of aqueous Pluronic F127 copolymer system

As one of the most widely used thermosensitive polymers, commercially available Pluronic F127 copolymer has been used as an attractive candidate for injectable hydrogel system. To tune its characteristics for better biomedical applications, the effects of collagen incorporation on its thermogelation in aqueous system and resultant hydrogel properties were investigated by dynamic rheological tests, scanning electron microscopic observation, in vitro drug release, and cytocompatibility assays. For its aqueous solution, the collagen incorporation was found to improve appropriately the sol–gel transition temperature for good injectability at room temperature and enhance obviously the temperature sensitivity for fast thermogelation. When compared to single Pluronic F127 copolymer thermogel, the composite thermogel with collagen showed a prolonged release for encapsulated drug and better cell compatibility. In addition, the effects on the morphology and viscoelastic behavior of resultant thermogel were also studied with respect to the concentration of incorporated collagen.