Novel biomimetic thermosensitive β-tricalcium phosphate/chitosan-based hydrogels for bone tissue engineering.

Among the less invasive surgical procedures for tissue engineering application, injectable in situ gelling systems have gained great attention. In this contest, this article is aimed to realize thermosensitive chitosan-based hydrogels, crosslinked with β-glycerophosphate and reinforced via physical interactions with β-tricalcium phosphate. The kinetics of sol-gel transition and the composite hydrogel properties were investigated by rheological analysis. The hydrogels were also characterized by Fourier transform infrared study, X-ray diffraction, scanning electron microscopy, transmission electron microscopy analysis, and thermal and biological studies. The hydrogels exhibit a gel-phase transition at body temperature, and a three-dimensional network with typical rheological properties of a strong gel. The presence of the inorganic phase, made up of nanocrystals, provides a structure with chemico-physical composition that mimics natural bone tissue, favoring cellular activity. These findings suggest the potential of the materials as promising candidates for hard tissue regeneration.